A retrospective analysis: incidence and risk factors of blood transfusion after lumbar spinal surgery

A retrospective analysis: incidence and risk factors of blood transfusion after lumbar spinal surgery | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article A retrospective analysis: incidence and risk factors of blood transfusion after lumbar spinal surgery Yuanyuan Huang, Changda Wu, Zihua Hao, Zhengfeng Dai, Wencheng Huang, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4529636/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background Blood transfusion is a frequently observed complication subsequent to lumbar spinal surgery (LSS), which may potentially result in a range of unfavorable consequences. However, a related large-scale multi-center analysis has not been conducted thus far. Methods A retrospective database analysis was performed using the Nationwide Inpatient Sample, which is the largest comprehensive hospital care database in the United States. The analysis included the data from 2010 to 2019, evaluating the patient's demographic characteristics, health system data, comorbidities, and medical and surgical issues during the perioperative process. Results There were 931,789 patients undergoing LSS..The overall incidence rate of blood transfusion was found to be 7.3%, generally decreasing from 8.6% in 2010 to 5.0% in 2019. Patients undergoing LSS with blood transfusions exhibited a higher prevalence of comorbidities, prolonged length of stay, increased total hospitalization costs, and elevated in-hospital mortality rates. These patients were associated with complications including thrombocytopenia, acute renal failure, deep venous thrombosis, pulmonary embolism, acute myocardial infarction, peripheral vascular disease, postoperative shock, gastrointestinal bleeding, chest pain, respiratory failure, heart failure, hemorrhage, and wound infection. Risk factors associated with blood transfusion included advanced age (≥ 65 years), female, alcohol abuse, deficiency anemia, rheumatoid diseases, chronic blood loss anemia, congestive heart failure, coagulopathy, metastatic cancer, obesity, peripheral vascular disorders, chronic renal failure, solid tumor without metastasis, valvular disease. Conclusion Blood transfusion emerges as a frequent complication following LSS and several risk factors were identified, which will help ensure safe management of postoperative patients and improve outcomes. Clinicians should pay more attention to these factors, thereby improving perioperative management. Lumbar spinal surgery lumbar decompression lumbar fusion blood transfusion risk factors Nationwide Inpatient Sample Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Introduction Lumbar spinal disorders represent a highly widespread category of musculoskeletal problems. Lumbar spinal surgery (LSS) is a prevalent operation to address lumbar spinal disorder, and over 500,000 surgeries were performed each year in the United States [ 1 , 2 ]. LSS mainly includes lumbar decompression (LD) and lumbar fusion (LF). Research has indicated that spinal stenosis is the prevailing indication for spinal decompression among individuals aged 65 years and above [ 3 ]. Moreover, spinal fusion serves as a viable treatment option for individuals experiencing low back pain due to lumbar instability and/or deformity. Prior research has provided evidence supporting the efficacy of surgical interventions in addressing degenerative lumbar spinal illness, particularly due to notable advancements in surgical methods and instrumentation [ 4 – 6 ]. Although lumbar spine surgery is now relatively successful and safe, complications still exist. Spinal surgery has been found to be potentially correlated with significant blood loss, necessitating the administration of perioperative blood transfusions (BT) in certain individuals. The results of a small sample retrospective cohort study showed that 8–36% of patients undergoing LSS required perioperative BT [ 7 ]. The primary objective of BT in this context is to enhance the blood's ability to carry oxygen, thus leading to improved tissue oxygenation [ 8 , 9 ]. There are several potential ways for blood transfusion (BT), including predonated autologous BT (PR-ABT), perioperative autologous BT (PEABT, encompassing both intraoperative and postoperative blood collection), and allogeneic BT (ALBT). It is also feasible to employ various combinations of BT approaches. While the transfer of infectious diseases through ALBT has become extremely rare [ 10 ], it is important to note that the process is not completely harmless. Apart from the risk of allergic reactions such as urticaria and anaphylaxis [ 11 ], ALBT may lead to adverse outcomes such as fever, hemodynamic overload, and hemolytic reactions [ 12 , 13 ]. In addition, other risks directly related to transfusion (e.g., transfusion errors and transfusion-transmissible infections) also affect the implementation of transfusion [ 14 ]. Additionally, BT has imposed heavy socioeconomic burdens on patients and healthcare system. Globally, it is estimated that approximately 85 million units of packed red blood cells are transfused annually [ 14 , 15 ]. Given that ALBT is a finite resource, the indications for BT have been more stricter. Thus, it is imperative to early identify which patients are at risk of receiving perioperative BT to improve surgical preparation, patient counseling, and blood protection, reduce BT related complications and effectively improve prognosis. It was reported that perioperative transfusion correlated with patient age, comorbidities, preoperative hemoglobin levels, duration of surgery, and procedural complexity [ 16 – 18 ]. Nevertheless, there is currently no large-scale multi-center analysis investigating the factors that increase the risks of requiring a BT undergoing LSS. Hence, the present study aimed to evaluate the incidence, temporal trends and risk factors associated with BT requirement in LD and LF by leveraging a comprehensive national database. Patient demographics, hospital characteristics, length of stay (LOS), total charges, in-hospital mortality, comorbidities, and perioperative complications were analyzed. Methods Study design The present study is a retrospective observational analysis conducted on a cohort of patients who underwent LD and LF procedures in the United States from the years 2010 to 2019. Data source We used the data files from the National Inpatient Sample (NIS) for our analysis. As a part of the Agency for Healthcare Research and Quality’s Healthcare Cost and Utilization Program, the NIS represents the largest database of fully paid hospitalizations in the United States. Each entry in the database represents a single hospitalization record. NIS collects stratified samples from more than 1000 hospitals, accounting for approximately 20% of annual hospital admissions in the United States [ 19 ]. A comprehensive synopsis on NIS data is available at http://www.hcup-us.ahrq.gov . Patient Selection We used the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) procedure codes 81.06–8 and 03.09, 80.51 to identify the patients treated with LF and LD. Besides, the ICD-10 procedure codes of LF (0SG007-Z, 0SG0037-Z, 0SG0047-Z) and LD (0ST20ZZ, 0ST40ZZ, 0SB20-4, 0SB40-4, 00CY0ZZ, 0SN20ZZ, 0SN40ZZ) were also used to enroll patients. To identify which patients required perioperative BT, the same ICD-9-CM and ICD-10 procedure codes as those employed in previous studies were utilized. Additional files show this in more detail [see Additional file 1 and Additional file 2]. Briefly, the patient cohort was stratified into two categories according to the presence or absence of BT events: patients without BT (reference group), and patients with BT requirements during the perioperative period of LSS (BT group). The BT group was compared with the reference group. Patients with missing data and younger than 18 years were excluded (Fig. 1 ). Demographic, health system, comorbidities and complications information Demographic data of patients (including age, gender, and race), admission type, hospital bed capacity, hospital teaching status, hospital location, hospital region, insurance type, and patient comorbidities were extracted from the NIS. ICD-9-CM and ICD-10 secondary diagnosis codes were used to identify associated in-hospital complications such as acute myocardial infarction, cardiac arrest, postoperative shock, acute heart failure, acute renal failure, continuous trauma ventilation, urinary tract infection, urinary retention, pneumonia, respiratory failure, pulmonary embolism, deep vein thrombosis, stroke, postoperative delirium, gastrointestinal bleeding, ileus, thrombocytopenia, septicemia, pyohemia, hemorrhage/seroma/hematoma, wound infection, nerve injuries, and wound rupture/not healing. Statistical analysis Univariable analysis was used to evaluate all potential variables associated with BT. Chi-squared and Wilcoxon rank test were applied to compare categorical variables and continuous variables respectively. Binary logistic regression analysis with stepwise regression was conducted to identify independent risk factors for BT subsequent to LSS and to examine the correlation of BT with other medical and surgical complications. The regression analysis in this study simultaneously included all variables pre-established by the NIS, such as demographics, hospital setting, and preoperative comorbidities (Table 1 ). The use of an alpha level of P ≤ 0.001 was chosen to indicate statistical significance due to the substantial sample size, a practice that has been employed in earlier investigations using the NIS database [ 20 ]. All statistical analyses were performed using the SPSS statistical software package (Version 26.0.0; SPSS, Inc., Chicago, IL). Table 1 Variables entered into the binary logistic regression analysis Variables Categories Specific Variables Patient demographics Age (≤ 64 years and ≥ 65 years), sex (male and female), race (White, Black, Hispanic, Asian or Pacific Islander, Native American and Other) Hospital characteristics Type of admission (non-elective, elective), bed size of hospital (small, medium, large), teaching status of hospital (nonteaching, teaching), location of hospital (rural, urban), type of insurance (Medicare, Medicaid, private insurance, self-pay, no charge, other), location of the hospital (northeast, Midwest or north central, south, west) Comorbidities AIDS, alcohol abuse, deficiency anemia, rheumatoid diseases/collagen vascular diseases, chronic blood loss anemia, congestive heart failure, chronic pulmonary disease, coagulopathy, depression, diabetes (uncomplicated), diabetes (with chronic complications), drug abuse, hypertension, hypothyroidism, liver disease, lymphoma, fluid and electrolyte disorders, metastatic cancer, other neurological disorders, obesity, paralysis, peripheral vascular disorders, psychoses, pulmonary circulation disorders, renal failure, solid tumor without metastasis, valvular disease, weight loss, and peptic ulcer disease excluding bleeding AIDS: Acquired immunodeficiency syndrome Results Incidence of BT in patients undergoing LD and LF This study included a total of 931,789 patients who had undergone LD or LF surgery from 2010 to 2019. This cohort was composed primarily of no BT (n = 863,873; 92.7%) and BT (n = 67,916; 7.3%) (Table 2 ). The rate of BT generally decreased from 8.6% in 2010 to 5.0% in 2019 (Fig. 2 ). Table 2 Patient characteristics and outcomes of BT after LSS (2010–2019) Characteristics No transfusion Transfusion P Total (n = count) 863,873 67,916 Total incidence (%) 7.3% Age (median, years) 59 (47–69) 63 (52–72) <0.0001 Age group (%) 18–44 17.8% 10.0% <0.0001 45–64 44.3% 36.6% 65–74 23.7% 28.5% ≥ 75 12.1% 17.2% Gender (%) Male 48.7% 39.7% <0.0001 Female 51.3% 60.3% Race (%) White 81.1% 77.1% <0.0001 Black 8.2% 9.8% Hispanic 6.4% 7.2% Asian or Pacific Islander 1.3% 2.0% Native American 0.5% 0.5% Other 2.6% 3.4% Number of Comorbidity (%) 0 0.0% 0.0% <0.0001 1 4.6% 1.4% 2 7.4% 2.4% ≥ 3 88.0% 96.2% LOS (median, d) 3 (1–4) 5 (4–8) <0.0001 TOTCHG (median, $) 71,359 (40,006-122,035) 142,839 (87,665 − 234,450) <0.0001 Type of insure (%) Medicare 39.5% 48.5% <0.0001 Medicaid 7.5% 8.1% Private insurance 42.9% 35.6% Self-pay 1.4% 1.4% No charge 0.2% 0.1% Other 8.5% 6.4% Bed size of hospital (%) Small 17.8% 18.2% 0.035 Medium 24.5% 24.2% Large 57.6% 57.6% Elective admission (%) 85% 78% <0.0001 Type of hospital (teaching %) 53.7% 57.6% <0.0001 Region of hospital (%) Northeast 16.2% 17.3% <0.0001 Midwest or North Central 22.9% 20.3% South 39.9% 40.3% West 21.0% 22.2% Location of hospital (urban, %) 94.4% 95.9% <0.0001 Died (%) 0.2% 0.9% <0.0001 BT: Blood transfusion, LLS: Lumbar spinal surgery, LOS: Length of stay, TOTCHG: Total charge The characteristics in patient demographics and hospital factors between the two surgery groups Table 2 describes the baseline characteristics (demographics and hospital characteristics) between two groups. Patients receiving BT were relatively older (63 years vs. 59 years, P < 0.0001). Consistently, a significant difference was observed in the age distribution between two groups, with a higher proportion of patients aged 75 years and older in the blood transfusion group (17.2% vs. 12.1%, P < 0.0001) (Table 2 and Fig. 3 A, B). Patients with BT requirements were 9% more likely to be female (60.3% vs 51.3%, P < 0.0001) (Table 2 ). Additionally, the race distribution between the two groups differed, with the Black demonstrating larger proportions in the transfusion group (Table 2 , and Fig. 3 C, D). As expected, teaching and urban hospitals demonstrated a higher BT incidence following LSS (P < 0.0001). Regarding to geographical location, perioperative BT more likely occurred in the Northeast and West, whereas less likely occurred in the Midwest or North Central regions (P < 0.0001) (Table 2 ). No significant difference was observed in terms of bed size of hospital. Adverse outcomes of BT after LSS Not surprisingly, patients undergoing LSS with multiple preoperative comorbidities (n ≥ 3) exhibited a 8.2% higher incidence of BT (96.2% vs. 88.0%, P < 0.0001) (Table 2 and Fig. 3 E, F). Correspondingly, inpatients mortality following LSS was significantly higher in those receiving BT (0.9% vs. 0.2%, P < 0.001) (Table 2 ). Therefore, these resulted in increased length of stay (LOS) and total charge (TOTCHG) for transfused patients. Median LOS increased from 3 days to 5 days (P < 0.0001), and median TOTCHG increased from $ 71,359 to $ 142,839 (P < 0.0001). Additionally, patients receiving BT were less likely to be electively admitted to hospital (78% vs. 85%, P < 0.0001). Risk factors related to BT after LSS Univariate analysis revealed that the prevalence of alcohol abuse (0.1%), deficiency anemia (16.8%), rheumatoid arthritis/collagen vascular diseases (5.2%), chronic blood loss anemia (2.1%), congestive heart failure (4.8%), coagulopathy (9.2%), depression (17.1%), drug abuse (2.7%), hypothyroidism (14.6%), lymphoma (0.8%), fluid and electrolyte disorders (23.9%), metastatic cancer (2.3%), other neurological disorders (6.8%), obesity (17.9%), paralysis (7.1%), peripheral vascular disorders (4.5%), psychoses (3.9%), pulmonary circulation disorders (2.1%), renal failure (7.8%), solid tumor without metastasis (1.3%), valvular disease (4.2%), weight loss (4.1%) and diabetes with chronic complications (5.4%) was significantly higher among patients receiving BTs after LSS (P < 0.0001). (Table 3 ). Table 3 Risk factors associated with BT after LSS Variable Multivariate Logistic Regression OR 95% CI P Age ≥ 65 years old 1.332 1.267-1.400 <0.0001 Female 1.466 1.462–1.514 <0.0001 Race White Ref - - Black 0.703 0.638–0.775 <0.0001 Hispanic 0.741 0.664–0.827 <0.0001 Asian or Pacific Islander 0.696 0.616–0.786 <0.0001 Native American 0.862 0.709–1.048 0.137 Other 1.026 0.800-1.318 0.838 Type of insurance Medicare Ref - - Medicaid 0.985 0.913–1.063 0.701 Private insurance 1.037 0.948–1.134 0.430 Self-pay 0.978 0.914–1.045 0.508 No charge 0.929 0.804–1.075 0.324 Other 0.696 0.475–1.020 0.063 Bed size of hospital Small Ref - - Medium 0.952 0.906–1.001 0.053 Large 1.279 1.230–1.330 <0.0001 Elective admission 1.099 1.052–1.148 0.002 Teaching hospital 1.111 1.073–1.150 <0.0001 Urban hospital 1.207 1.114–1.307 <0.0001 Region of hospital Northeast Ref - - Midwest or North Central 0.986 0.935–1.050 0.655 South 1.041 0.979–1.108 0.200 West 1.155 1.094–1.218 <0.0001 BT: Blood transfusion, LLS: Lumbar spinal surgery Logistic regression analysis was used to investigate the risk factors associated with BT after LSS (Table 3 ), and the final indicators were determined as follows: for patient demographics and hospital characteristics, it was found that age ≥ 65 years old (odds ratio [OR] = 1.332; 95% confidence interval [CI] = 1.267-1.400; P < 0.0001), female (OR = 1.466; CI = 1.462–1.514; P < 0.0001), large bed size of hospital (OR = 1.279; CI = 1.230–1.330; P < 0.0001), elective admission (OR = 1.099; CI = 1.052–1.148; P < 0.0001), teaching hospital (OR = 1.111; CI = 1.073–1.150; P < 0.0001), urban hospital (OR = 1.207; CI = 1.114–1.307; P < 0.0001) to be risk factors for BT after LSS. Interestingly, we additionally found that being black (OR = 0.703; CI = 0.638–0.775; P < 0.0001), Hispanic (OR = 0.741; CI = 0.664–0.827; P < 0.0001) and Asian or Pacific Islander (OR = 0.696; CI = 0.616–0.786; P < 0.0001) were protective factors. Regarding comorbidities, we ultimately identified alcohol abuse (OR = 1.247; CI = 1.112–1.399; P < 0.0001), deficiency anemia (OR = 2.720; CI = 2.598–2.847; P < 0.0001), rheumatoid diseases/collagen vascular diseases (OR = 1.206; CI = 1.115–1.304; P < 0.0001), chronic blood loss anemia (OR = 5.765; CI = 5.082–6.539; P < 0.0001), congestive heart failure (OR = 1.318; CI = 1.202–1.446; P < 0.0001), coagulopathy (OR = 3.560; CI = 3.300-3.841; P < 0.0001), depression (OR = 1.131; CI = 1.081–1.183; P < 0.0001), drug abuse (OR = 1.339; CI = 1.180–1.520; P < 0.0001), hypothyroidism (OR = 1.093; CI = 1.040–1.148; P < 0.0001), lymphoma (OR = 2.029; CI = 1.652–2.493; P < 0.0001), fluid and electrolyte disorders (OR = 2.530; CI = 2.418–2.648; P < 0.0001), metastatic cancer (OR = 2.312; CI = 2.017–2.649; P < 0.0001), other neurological disorders (OR = 1.231; CI = 1.148–1.320; P < 0.0001), obesity (OR = 1.118; CI = 1.067–1.173; P < 0.0001), paralysis (OR = 1.526; CI = 1.413–1.649; P < 0.0001), peripheral vascular disorders (OR = 1.347; CI = 1.232–1.473; P < 0.0001), psychoses (OR = 1.183; CI = 1.078–1.297; P < 0.0001), pulmonary circulation disorders (OR = 1.506; CI = 1.317–1.722; P < 0.0001), renal failure (OR = 1.324; CI = 1.222–1.435; P < 0.0001), solid tumor without metastasis (OR = 1.444; CI = 1.197–1.742; P < 0.0001), valvular disease (OR = 1.332; CI = 1.222–1.452; P < 0.0001) and weight loss (OR = 1.545; CI = 1.387–1.722; P < 0.0001) as risk factors for BT after LSS (Table 4 ). Table 4 Relationship between BT and preoperative comorbidities Comorbidities Univariate Analysis Multivariate Logistic Regression No transfusion Transfusion P OR 95% CI P Preoperative comorbidities Acquired immune deficiency syndrome 1034 (0.1%) 95 (0.1%) 0.145 1.190 0.713–1.987 0.506 Alcohol abuse 13,425 (1.6%) 1798 (2.6%) < 0.0001 1.336 1.203–1.485 <0.0001 Deficiency anemia 40,124 (4.6%) 11,397 (16.8%) < 0.0001 2.724 2.611–2.842 <0.0001 Rheumatoid arthritis/collagen vascular diseases 29,302 (3.4%) 3553 (5.2%) < 0.0001 1.263 1.175–1.358 <0.0001 Chronic blood loss anemia 3189 (0.4%) 1452 (2.1%) < 0.0001 5.806 5.151–6.544 <0.0001 Congestive heart failure 17,689 (2.0%) 3229 (4.8%) < 0.0001 1.318 1.209–1.438 <0.0001 Chronic pulmonary disease 135,318 (15.7%) 12,461 (18.3%) < 0.0001 0.963 0.924–1.003 0.072 Coagulopathy 14,044 (1.6%) 6244 (9.2%) < 0.0001 3.455 3.216–3.712 <0.0001 Depression 126,350 (14.6%) 11,611 (17.1%) < 0.0001 1.166 1.117–1.217 <0.0001 Diabetes, uncomplicated 133,996 (15.5%) 11,193 (16.5%) < 0.0001 0.941 0.902–0.982 0.005 Drug abuse 14,114 (1.6%) 1830 (2.7%) < 0.0001 1.557 1.393–1.741 <0.0001 Hypertension 443,579 (51.3%) 39,066 (57.5%) < 0.0001 1.046 1.010–1.084 0.012 Hypothyroidism 95,798 (11.1%) 9907 (14.6%) < 0.0001 1.091 1.041–1.142 <0.0001 Liver disease 11,813 (1.4%) 1716 (2.5%) < 0.0001 1.189 1.052–1.343 0.005 Lymphoma 2356 (0.3%) 563 (0.8%) < 0.0001 1.989 1.633–2.389 <0.0001 Fluid and electrolyte disorders 62,114 (7.2%) 16,232 (23.9%) < 0.0001 2.454 2.351–2.561 <0.0001 Metastatic cancer 4796 (0.6%) 1550 (2.3%) < 0.0001 2.479 2.189–2.807 <0.0001 Other neurological disorders 31,359 (3.6%) 4621 (6.8%) < 0.0001 1.175 1.100-1.255 <0.0001 Obesity 139,402 (16.1%) 12,128 (17.9%) < 0.0001 1.196 1.144–1.249 <0.0001 Paralysis 25,478 (2.9%) 4816 (7.1%) < 0.0001 1.399 1.303–1.502 <0.0001 Peripheral vascular disorders 20,946 (2.4%) 3051 (4.5%) < 0.0001 1.336 1.230–1.451 <0.0001 Psychoses 23,974 (2.8%) 2654 (3.9%) < 0.0001 1.329 1.224–1.443 <0.0001 Pulmonary circulation disorders 5420 (0.6%) 1435 (2.1%) < 0.0001 1.546 1.362–1.755 <0.0001 Renal failure 30,346 (3.5%) 5279 (7.8%) < 0.0001 1.293 1.201–1.393 <0.0001 Solid tumor without metastasis 4795 (0.6%) 898 (1.3%) < 0.0001 1.595 1.351–1.885 <0.0001 Valvular disease 19,497 (2.3%) 2884 (4.2%) < 0.0001 1.296 1.195–1.406 <0.0001 Weight loss 7897 (0.9%) 2793 (4.1%) < 0.0001 1.645 1.488–1.819 <0.0001 Peptic ulcer disease excluding bleeding 731 (0.1%) 90 (0.1%) < 0.0001 3.874 1.544–9.722 0.004 BT: Blood transfusion, OR: Odds ratio, CI: Confidence interval Correlation analysis between BT and postoperative complications In terms of postoperative complications, patients receiving perioperative BT were found to have higher incidence of complications including: acute myocardial infarction (1.8%), postoperative shock (0.6%), acute heart failure (4.0%), acute renal failure (7.1%), urinary tract infection (7.5%), urinary retention (7.4%), pneumonia (4.6%), continuous trauma ventilation (5.1%), respiratory failure (3.8%), pulmonary embolism (1.1%), deep vein thrombosis (2.0%), stroke (1.8%), postoperative delirium (3.0%), gastrointestinal bleeding (0.5%), ileus (5.4%), thrombocytopenia (7.2%), septicemia (3.2%), hemorrhage/seroma/hematoma (3.6%), wound infection (1.3%), nerve injuries (4.3%), and wound rupture/not healing (0.7%) (P < 0.0001) (Table 5 ). Table 5 Relationship between BT and postoperative complications Complications Univariate Analysis Multivariate Logistic Regression No transfusion Transfusion P OR 95% CI P Medical complications Acute myocardial infarction 3953 (0.5%) 1223 (1.8%) < 0.0001 1.926 1.790–2.073 <0.0001 Cardiac arrest 969 (0.1%) 277 (0.4%) < 0.0001 0.589 0.504–0.609 <0.0001 Postoperative shock 531 (0.1%) 407 (0.6%) < 0.0001 3.016 2.592–3.509 <0.0001 Acute heart failure 14,133 (1.6%) 2739 (4.0%) < 0.0001 1.549 1.480–1.622 <0.0001 Acute renal failure 15,824 (1.8%) 4851 (7.1%) < 0.0001 1.262 1.188–1.341 <0.0001 Urinary tract infection 23,581 (2.7%) 5067 (7.5%) < 0.0001 1.192 1.130–1.259 <0.0001 Urinary retention 37,393 (4.3%) 5021 (7.4%) < 0.0001 1.262 1.221–1.304 <0.0001 Continuous trauma ventilation 8443 (1.0%) 3468 (5.1%) < 0.0001 2.160 2.052–2.274 <0.0001 Pneumonia 10,292 (1.2%) 3110 (4.6%) < 0.0001 1.241 1.179–1.306 <0.0001 Respiratory failure 7858 (0.9%) 2596 (3.8%) < 0.0001 1.458 1.379–1.541 <0.0001 Pulmonary embolism 2285 (0.3%) 756 (1.1%) < 0.0001 1.580 1.437–1.737 <0.0001 Deep vein thrombosis 4025 (0.5%) 1373 (2.0%) < 0.0001 1.609 1.498–1.728 <0.0001 Stroke 6953 (0.8%) 1227 (1.8%) < 0.0001 1.118 0.933–1.341 0.228 Postoperative delirium 7126 (0.8%) 2052 (3.0%) < 0.0001 2.143 2.030–2.262 <0.0001 Gastrointestinal bleeding 703 (0.1%) 338 (0.5%) < 0.0001 1.954 1.684–2.268 <0.0001 Ileus 14,782 (1.7%) 3669 (5.4%) < 0.0001 2.180 2.088–2.276 <0.0001 Thrombocytopenia 10,669 (1.2%) 4916 (7.2%) < 0.0001 4.244 4.089–4.405 <0.0001 Septicemia 5927 (0.7%) 2180 (3.2%) < 0.0001 1.365 0.488–3.823 0.553 Surgical complications Hemorrhage/seroma/hematoma 7378 (0.9%) 2431 (3.6%) < 0.0001 2.777 2.639–2.923 <0.0001 Wound infection 3821 (0.4%) 889 (1.3%) < 0.0001 1.374 1.263–1.496 <0.0001 Nerve injuries 25,427 (2.9%) 2907 (4.3%) < 0.0001 1.255 1.204–1.307 <0.0001 Wound rupture/not healing 1744 (0.2%) 471 (0.7%) < 0.0001 1.331 1.183–1.498 <0.0001 BT: Blood transfusion, OR: Odds ratio, CI: Confidence interval In multivariate analysis, BT was associated with acute myocardial infarction (OR = 1.926; CI = 1.790–2.073), postoperative shock (OR = 3.016; CI = 2.592–3.509), acute heart failure (OR = 1.926; CI = 1.790–2.073), acute renal failure (OR = 1.262; CI = 1.188–1.341), urinary tract infection (OR = 1.192; CI = 1.130–1.259), urinary retention (OR = 1.262; CI = 1.221–1.304), continuous trauma ventilation (OR = 2.160; CI = 2.052–2.274), pneumonia (OR = 1.241; CI = 1.179–1.306), respiratory failure (OR = 1.458; CI = 1.379–1.541), pulmonary embolism (OR = 1.580; CI = 1.437–1.737), deep vein thrombosis (OR = 1.609; CI = 1.498–1.728), postoperative delirium (OR = 2.143; CI = 2.030–2.262), gastrointestinal bleeding (OR = 1.954; CI = 1.684–2.268), ileus (OR = 2.180; CI = 2.088–2.276), thrombocytopenia (OR = 4.244; CI = 4.089–4.405), hemorrhage/seroma/hematoma (OR = 2.777; CI = 2.639–2.923), wound infection (OR = 1.374; CI = 1.263–1.496), nerve injuries (OR = 1.255; CI = 1.204–1.307), and wound rupture/not healing (OR = 1.331; CI = 1.183–1.498; P < 0.0001) (Table 5 ). Discussion This study demonstrates a national health-economic investigation of patients receiving perioperative BT after LSS. Given the improvement of component design, progress in surgical techniques [ 21 , 22 ], striction of transfusion managements [ 23 – 25 ], there was a reduction of BT incidence from 2010 to 2019 generally (from 8.6 to 5.0%) (Fig. 2 ). Importantly, this finding has not been reported to date. Although transfusion rate decreased annually, the overall transfusion rate in the patients undergoing LSS remained high. Consequently, it is essential to investigate the risk factors associated with BT in LSS for more effective management. Notably, patients with BT requirement undergoing LSS accompanied with adverse clinical outcomes such as more comorbidities, extended LOS, increased total charge, and elevated inpatient mortality, which further emphasize the necessity to explore the risk factors associated with BT. Our study found that advanced age and female gender were associated with a high risk of postoperative blood transfusion after LSS. In demographic analysis, patients receiving BT were 4 years older than those without. Additionally, the age distribution revealed that elderly patients (≥ 65 years) occupied a greater proportion in the BT group. Moreover, the logistic regression analysis demonstrated that aged over 65 years and females were risk factors for BT after LSS (Table 5 ). A potential reason is that elderly individuals with decreased bone marrow function, hematopoietic capacity, and physiological reserve [ 26 – 28 ]. Female patients often exhibit lower baseline hemoglobin levels compared to male patients probably due to the variations in hormonal levels and a greater prevalence of iron deficiency anemia resulting from menstrual blood loss [ 29 ]. One possible explanation accounting for teaching hospital and urban hospital as risk factors associated with perioperative BT (Fig. 4 A, B, C, and D) is that patients in these institutions are commonly challenging with complex surgeries and more comorbidities [ 30 ]. Deficiency anemia, chronic blood loss anemia, and coagulopathy were identified as risk factors for BT in the present study, which was met our expectations (Fig. 4 E and F). This is possibly correlated with lower preoperative hemoglobin levels in these patients. Preoperative coagulation dysfunction may contribute to substantial intraoperative blood loss, necessitating perioperative transfusion [ 31 , 32 ]. Additionally, cardiovascular diseases including congestive heart failure, valvular disease, peripheral vascular disease, pulmonary circulation disorders, and hypertension can lead to organ hypoxia, ischemia, and inadequate blood volume, thereby increasing the likelihood of transfusion. Furthermore, comorbidities such as diabetes with chronic complications, rheumatoid arthritis/collagen vascular diseases, and hypothyroidism were confirmed as risk factors of BT. These diseases are either systemic autoimmune disorders or strongly associated with systemic autoimmune disorders, elevating the likelihood of preoperative anemia and low protein levels [ 33 ]. Moreover, lymphoma, solid tumor without metastasis, metastatic cancer, liver disease, paralysis, peptic ulcer disease excluding bleeding, fluid and electrolyte disorders, obesity, and weight loss were also found to be risk factors of BT in this study,which may be attributed to that patients with these consumptive or malnourished comorbidities commonly experience low hematopoietic capacity, preoperative anemia, or extra blood loss [ 34 ]. A possible explanation for chronic renal failure as a risk factor may be that it reduces the efficiency of red blood cell production and red blood cell lifespan, leading to anemia and consequently necessitating transfusion [ 35 ]. In addition, alcohol abuse, depression, psychoses, drug abuse, and other neurological disorders were identified as independent risk factors for requiring BT after LSS. After transfusion, there is an increased likelihood of acute renal failure, possibly due to that the BT may increase in circulating free iron and exacerbating perioperative stress injury, which is associated with renal organ damage [ 36 ]. As previously mentioned, chronic renal failure is one of the risk factors associated with BT. Therefore, a plausible explanation may be that BT has a strong correlation with kidney damage. Moreover, BT is associated with acute myocardial infarction, acute heart failure, deep vein thrombosis, and thrombocytopenia. Changes in blood viscosity may lead to thrombosis, increased circulatory volume, and subsequent cardiac strain [ 37 ]. In patients with acute myocardial infarction, persistently elevated hemoglobin levels may improve clinical outcomes by increasing oxygen delivery to the myocardium, potentially contributing to the occurrence of transfusion [ 38 ]. Although thrombocytopenia is not a common complication of transfusion, the possibility of transfusion-related thrombocytopenia cannot be ruled out in massive transfusion [ 39 ]. Conversely, as mentioned earlier, cardiovascular diseases such as chronic heart failure are also risk factors for BT. Our study also indicates that BT after LSS is associated with perioperative infectious complications, including septicemia, pneumonia, wound infections, hemorrhage/seroma/hematoma, wound rupture/not healing, and urinary tract infection. The impact of BT on infectious complications may be related to blood processing methods, blood storage techniques, and bacterial contamination [ 40 ]. Patients with infections are more likely to receive transfusions, possibly because infections result in greater circulatory dysfunction, predispose to anemia and transfusion [ 41 ]. Therefore, it was found that the aforementioned complications and BT are associated, but causality cannot be proven clearly. Due to methodological limitations of observational and database studies, inferring causality between transfusion and adverse outcomes remains challenging. In summary, BT was associated with numerous comorbidities and complications (Figs. 5 and 6 ). Patients with certain comorbidities may have a higher risk of transfusion during the perioperative period due to the baseline anemia, and certain related complications may adversely affect perioperative patients. Therefore, developing strategies to reduce the need for BT remains important for orthopedic surgeons to minimize avoidable risks. By identifying high-risk patients, perioperative management can be optimized and more informed patient counseling can occur before surgery. Many interventions have demonstrated efficacy in mitigating blood loss and minimizing the necessity for transfusions. These interventions encompass the augmented utilization of spinal anesthesia, administration of tranexamic acid, implementation of blood management protocols that do not rely on stringent transfusion triggers, adoption of less aggressive chemical anticoagulants, and utilization of hemostatic agents [ 42 – 45 ]. By employing these interventions, it is possible to effectively diminish both blood loss and the need for transfusions. Given that this study utilizes the NIS database, there are some limitations. Initially, it should be noted that the NIS database only captures patient information prior to discharge. Consequently, any post-discharge issues are not accounted for in the database. The analysis of solely early medical records introduces a potential constraint that could result in an underestimation of the occurrence of transfusions. Secondly, the NIS does not include detailed clinical information such as the type of anesthesia used, amount of blood loss, perioperative hemoglobin values, and the number or volume of transfusion units, but it does not affect the analysis of risk factors directly. Furthermore, due to the lack of other risk variables in the NIS database, our analysis was limited to the risk factors recorded in this database. Another limitation is that the most recent data are from 2019, which may not fully explain recent changes in transfusion rates. Additionally, the etiology associated with the results obtained from this retrospective database analysis requires further validation. Conclusion BT is a common complication after LSS, especially in the elderly and women, with an overall incidence rate of 7.3%. The yearly occurrence of BT following LSS exhibited a decline tendency from 2010 to 2019. This study identified several risk factors, including advanced age (≥ 65 years), female, large bed size of hospital, elective admission, teaching hospital, urban hospital, alcohol abuse, deficiency anemia, rheumatoid diseases/collagen vascular diseases, chronic blood loss anemia, congestive heart failure, coagulopathy, depression, drug abuse, hypothyroidism, lymphoma, fluid and electrolyte disorders, metastatic cancer, other neurological disorders, obesity, paralysis, peripheral vascular disorders, psychoses, pulmonary circulation disorders, renal failure, solid tumor without metastasis, valvular disease and weight loss. Additionally, the occurrence of BT was correlated with an increased length of hospital stay (LOS), TOTCHG and mortality. Moreover, BT was associated with urinary tract infection, thrombocytopenia, acute renal failure, pneumonia, gastrointestinal complication, DVT, genitourinary disease, PE, AMI, peripheral vascular disease, respiratory disease, postoperative delirium, postoperative shock, GI bleeding, chest pain, ileus, urinary retention, respiratory failure, continuous trauma ventilation, arrhythmia, heart failure, hemorrhage/seroma/hematoma, wound infection, lower nerve injuries, and wound rupture/not healing. By identifying high-risk patients, surgeons can counsel patients better and optimize management to reduce the requirement of BTs. Abbreviations LSS Lumbar spinal surgery LD Lumbar decompression LF Lumbar fusion LIF Lumbar interbody fusion ALIF Anterior lumbar interbody fusion PLIF Posterior lumbar interbody fusion TLIF Transforaminal lumbar interbody fusion BT Blood transfusion PR-ABT Predonated autologous blood transfusion PEABT Perioperative autologous blood transfusion ALBT Allogeneic blood transfusion THA Total hip arthroplasty NIS Nationwide Inpatient Sample LOS Length of stay TOTCHG Total charge OR Odds ratio CI Confidence interval Declarations Ethics approval and consent to participate Not applicable. Consent for publication Not applicable. Data availability The datasets are available at https://www.ahrq.gov/data/hcup/index.html. Competing interests The authors declare no competing interests. Funding This work was supported by the President Foundation of Nanfang Hospital, Southern Medical University [2021]33 and the Guangdong Provincial Department of Education [2021]29. 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Carson JL, Brooks MM, Chaitman BR, Alexander JH, Goodman SG, Bertolet M, Abbott JD, Cooper HA, Rao SV, Triulzi DJ, Fergusson DA, Kostis WJ, Noveck H, Simon T, Steg PG, DeFilippis AP, Goldsweig AM, Lopes RD, White H, Alsweiler C, Morton E, Hébert PC. MINT Investigators. Rationale and design for the myocardial ischemia and transfusion (MINT) randomized clinical trial. Am Heart J. 2023;257:120–9. Sihler KC, Napolitano LM. Complications of massive transfusion. Chest. 2010;137(1):209–20. Vamvakas EC, Blajchman MA. Blood still kills: six strategies to further reduce allogeneic blood transfusion-related mortality. Transfus Med Rev. 2010;24(2):77–124. 10.1016/j.tmrv.2009.11.001 . Erratum in: Transfus Med Rev. 2010;24(3):257. Cao X, Liu X, Zhang X, Zhang K, Chen C, Yang Q, Wang J, Li X, Wei L. Risk factors for perioperative blood transfusion in patients undergoing total laparoscopic hysterectomy. BMC Womens Health. 2024;24(1):65. Lessing NL, Edwards CC 2nd, Dean CL, Waxter OH, Lin C, Curto RA, Brown CH 4. th. Spinal Anesthesia for Geriatric Lumbar Spine Surgery: A Comparative Case Series. Int J Spine Surg. 2020;14(5):713–21. Todeschini AB, Uribe AA, Echeverria-Villalobos M, Fiorda-Diaz J, Abdel-Rasoul M, McGahan BG, Grossbach AJ, Viljoen S, Bergese SD. Efficacy of Intravenous Tranexamic Acid in Reducing Perioperative Blood Loss and Blood Product Transfusion Requirements in Patients Undergoing Multilevel Thoracic and Lumbar Spinal Surgeries: A Retrospective Study. Front Pharmacol. 2020;11:566956. Kang T, Park SY, Nam JJ, Lee SH, Park JH, Suh SW. Patient Blood Management During Lumbar Spinal Fusion Surgery. World Neurosurg. 2019;130:e566–72. Lentschener C, Cottin P, Bouaziz H, Mercier FJ, Wolf M, Aljabi Y, Boyer-Neumann C, Benhamou D. Reduction of blood loss and transfusion requirement by aprotinin in posterior lumbar spine fusion. Anesth Analg. 1999;89(3):590–7. Additional Declarations No competing interests reported. Supplementary Files Additionalfile1.docx Additionalfile2.docx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4529636","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":319181476,"identity":"629f9cd0-86f4-4bf7-9bd0-db12ff99ee33","order_by":0,"name":"Yuanyuan Huang","email":"","orcid":"","institution":"Dongguan Polytechnic","correspondingAuthor":false,"prefix":"","firstName":"Yuanyuan","middleName":"","lastName":"Huang","suffix":""},{"id":319181479,"identity":"171f5191-158e-4b4e-8389-1c15a4c8a200","order_by":1,"name":"Changda Wu","email":"","orcid":"","institution":"Southern Medical 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17:17:10","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4529636/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4529636/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":60198768,"identity":"1b609054-9dc9-4ed9-836a-ba6b194c4875","added_by":"auto","created_at":"2024-07-13 02:14:29","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":314768,"visible":true,"origin":"","legend":"\u003cp\u003eExclusion process for patients undergoing lumbar spinal surgery with blood transfusion\u003c/p\u003e","description":"","filename":"F1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4529636/v1/2350a0f5047cc13d4b73f98e.jpg"},{"id":60198770,"identity":"9fc1684e-f9b1-48a5-9459-3839ebcf3a1d","added_by":"auto","created_at":"2024-07-13 02:14:29","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":244048,"visible":true,"origin":"","legend":"\u003cp\u003eThe annual incidence of postoperative blood transfusion following lumbar spinal surgery from 2010 to 2019\u003c/p\u003e","description":"","filename":"F2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4529636/v1/5fa82073fe11c58493ad185a.jpg"},{"id":60198772,"identity":"7a273158-1561-44f7-adbd-6e2df1edc4c2","added_by":"auto","created_at":"2024-07-13 02:14:29","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":334496,"visible":true,"origin":"","legend":"\u003cp\u003eThe characteristics in patient demographics and hospital factors between the two surgery groups. \u003cstrong\u003eA\u003c/strong\u003e: The age distribution characteristics of patients who did not receive a blood transfusion postoperatively. \u003cstrong\u003eB\u003c/strong\u003e: The age distribution characteristics of patients who received a blood transfusion postoperatively. \u003cstrong\u003eC\u003c/strong\u003e: The racial distribution characteristics of patients who did not receive a blood transfusion postoperatively. \u003cstrong\u003eD\u003c/strong\u003e: The racial distribution characteristics of patients who received a blood transfusion postoperatively. \u003cstrong\u003eE\u003c/strong\u003e: The number of preoperative comorbidities in patients who did not receive a blood transfusion postoperatively. \u003cstrong\u003eF\u003c/strong\u003e: The number of preoperative comorbidities in patients who received a blood transfusion postoperatively.\u003c/p\u003e","description":"","filename":"F3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4529636/v1/78291164dc25d809b4f4d843.jpg"},{"id":60199200,"identity":"cfe834e0-1e1f-45bc-b5e5-a6a8eaa1e8e8","added_by":"auto","created_at":"2024-07-13 02:22:29","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":316185,"visible":true,"origin":"","legend":"\u003cp\u003eHospital characteristics between the two surgical groups. \u003cstrong\u003eA\u003c/strong\u003e: Whether the hospitals where patients who did not receive a blood transfusion postoperatively were treated are teaching hospitals. \u003cstrong\u003eB\u003c/strong\u003e: Whether the hospitals where patients who received a blood transfusion postoperatively were treated are teaching hospitals. \u003cstrong\u003eC\u003c/strong\u003e: Whether the hospitals where patients who did not receive a blood transfusion postoperatively were treated are urban hospitals. \u003cstrong\u003eD\u003c/strong\u003e: Whether the hospitals where patients who received a blood transfusion postoperatively were treated are urban hospitals. \u003cstrong\u003eE\u003c/strong\u003e: The regional distribution characteristics of the hospitals where patients who did not receive a blood transfusion postoperatively were treated. \u003cstrong\u003eF\u003c/strong\u003e: The regional distribution characteristics of the hospitals where patients who received a blood transfusion postoperatively were treated.\u003c/p\u003e","description":"","filename":"F4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4529636/v1/dc3beaa5cca58caff463a754.jpg"},{"id":60199201,"identity":"dbedd903-e68b-46a4-898f-04a1107f80ba","added_by":"auto","created_at":"2024-07-13 02:22:29","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":344924,"visible":true,"origin":"","legend":"\u003cp\u003eIncidence of preoperative comorbidities related to blood transfusion\u003c/p\u003e","description":"","filename":"F5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4529636/v1/b39e347621711096a812e791.jpg"},{"id":60198773,"identity":"a63c1033-1c9d-4e18-9215-157571324cf4","added_by":"auto","created_at":"2024-07-13 02:14:29","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":344973,"visible":true,"origin":"","legend":"\u003cp\u003eIncidence of postoperative complications related to blood transfusion\u003c/p\u003e","description":"","filename":"F6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4529636/v1/12ae32daf7d120796659bfbe.jpg"},{"id":65808102,"identity":"f924fd48-eb66-455c-a19f-5e7e5a02df6d","added_by":"auto","created_at":"2024-10-03 03:38:45","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3205571,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4529636/v1/fc48909d-e0d9-426a-a78c-c33bbaf57b05.pdf"},{"id":60199202,"identity":"e17daac0-8d0b-46b5-9a2a-bb8c68a05bd4","added_by":"auto","created_at":"2024-07-13 02:22:29","extension":"docx","order_by":8,"title":"","display":"","copyAsset":false,"role":"supplement","size":12894,"visible":true,"origin":"","legend":"","description":"","filename":"Additionalfile1.docx","url":"https://assets-eu.researchsquare.com/files/rs-4529636/v1/d5a1edc549f1dd235e1054d1.docx"},{"id":60198775,"identity":"7c9dfc6c-0615-49bb-9627-92f5e9ac3447","added_by":"auto","created_at":"2024-07-13 02:14:29","extension":"docx","order_by":9,"title":"","display":"","copyAsset":false,"role":"supplement","size":13424,"visible":true,"origin":"","legend":"","description":"","filename":"Additionalfile2.docx","url":"https://assets-eu.researchsquare.com/files/rs-4529636/v1/e3d5f26c42b6cdbcda92b694.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"A retrospective analysis: incidence and risk factors of blood transfusion after lumbar spinal surgery","fulltext":[{"header":"Introduction","content":"\u003cp\u003eLumbar spinal disorders represent a highly widespread category of musculoskeletal problems. Lumbar spinal surgery (LSS) is a prevalent operation to address lumbar spinal disorder, and over 500,000 surgeries were performed each year in the United States [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. LSS mainly includes lumbar decompression (LD) and lumbar fusion (LF). Research has indicated that spinal stenosis is the prevailing indication for spinal decompression among individuals aged 65 years and above [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Moreover, spinal fusion serves as a viable treatment option for individuals experiencing low back pain due to lumbar instability and/or deformity. Prior research has provided evidence supporting the efficacy of surgical interventions in addressing degenerative lumbar spinal illness, particularly due to notable advancements in surgical methods and instrumentation [\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Although lumbar spine surgery is now relatively successful and safe, complications still exist.\u003c/p\u003e \u003cp\u003eSpinal surgery has been found to be potentially correlated with significant blood loss, necessitating the administration of perioperative blood transfusions (BT) in certain individuals. The results of a small sample retrospective cohort study showed that 8\u0026ndash;36% of patients undergoing LSS required perioperative BT [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. The primary objective of BT in this context is to enhance the blood's ability to carry oxygen, thus leading to improved tissue oxygenation [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. There are several potential ways for blood transfusion (BT), including predonated autologous BT (PR-ABT), perioperative autologous BT (PEABT, encompassing both intraoperative and postoperative blood collection), and allogeneic BT (ALBT). It is also feasible to employ various combinations of BT approaches. While the transfer of infectious diseases through ALBT has become extremely rare [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e], it is important to note that the process is not completely harmless. Apart from the risk of allergic reactions such as urticaria and anaphylaxis [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e], ALBT may lead to adverse outcomes such as fever, hemodynamic overload, and hemolytic reactions [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. In addition, other risks directly related to transfusion (e.g., transfusion errors and transfusion-transmissible infections) also affect the implementation of transfusion [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Additionally, BT has imposed heavy socioeconomic burdens on patients and healthcare system. Globally, it is estimated that approximately 85\u0026nbsp;million units of packed red blood cells are transfused annually [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Given that ALBT is a finite resource, the indications for BT have been more stricter. Thus, it is imperative to early identify which patients are at risk of receiving perioperative BT to improve surgical preparation, patient counseling, and blood protection, reduce BT related complications and effectively improve prognosis. It was reported that perioperative transfusion correlated with patient age, comorbidities, preoperative hemoglobin levels, duration of surgery, and procedural complexity [\u003cspan additionalcitationids=\"CR17\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Nevertheless, there is currently no large-scale multi-center analysis investigating the factors that increase the risks of requiring a BT undergoing LSS.\u003c/p\u003e \u003cp\u003eHence, the present study aimed to evaluate the incidence, temporal trends and risk factors associated with BT requirement in LD and LF by leveraging a comprehensive national database. Patient demographics, hospital characteristics, length of stay (LOS), total charges, in-hospital mortality, comorbidities, and perioperative complications were analyzed.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy design\u003c/h2\u003e \u003cp\u003eThe present study is a retrospective observational analysis conducted on a cohort of patients who underwent LD and LF procedures in the United States from the years 2010 to 2019.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eData source\u003c/h2\u003e \u003cp\u003eWe used the data files from the National Inpatient Sample (NIS) for our analysis. As a part of the Agency for Healthcare Research and Quality\u0026rsquo;s Healthcare Cost and Utilization Program, the NIS represents the largest database of fully paid hospitalizations in the United States. Each entry in the database represents a single hospitalization record. NIS collects stratified samples from more than 1000 hospitals, accounting for approximately 20% of annual hospital admissions in the United States [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. A comprehensive synopsis on NIS data is available at \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://www.hcup-us.ahrq.gov\u003c/span\u003e\u003cspan address=\"http://www.hcup-us.ahrq.gov\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003ePatient Selection\u003c/h2\u003e \u003cp\u003eWe used the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) procedure codes 81.06\u0026ndash;8 and 03.09, 80.51 to identify the patients treated with LF and LD. Besides, the ICD-10 procedure codes of LF (0SG007-Z, 0SG0037-Z, 0SG0047-Z) and LD (0ST20ZZ, 0ST40ZZ, 0SB20-4, 0SB40-4, 00CY0ZZ, 0SN20ZZ, 0SN40ZZ) were also used to enroll patients. To identify which patients required perioperative BT, the same ICD-9-CM and ICD-10 procedure codes as those employed in previous studies were utilized. Additional files show this in more detail [see Additional file 1 and Additional file 2]. Briefly, the patient cohort was stratified into two categories according to the presence or absence of BT events: patients without BT (reference group), and patients with BT requirements during the perioperative period of LSS (BT group). The BT group was compared with the reference group. Patients with missing data and younger than 18 years were excluded (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eDemographic, health system, comorbidities and complications information\u003c/h2\u003e \u003cp\u003eDemographic data of patients (including age, gender, and race), admission type, hospital bed capacity, hospital teaching status, hospital location, hospital region, insurance type, and patient comorbidities were extracted from the NIS.\u003c/p\u003e \u003cp\u003eICD-9-CM and ICD-10 secondary diagnosis codes were used to identify associated in-hospital complications such as acute myocardial infarction, cardiac arrest, postoperative shock, acute heart failure, acute renal failure, continuous trauma ventilation, urinary tract infection, urinary retention, pneumonia, respiratory failure, pulmonary embolism, deep vein thrombosis, stroke, postoperative delirium, gastrointestinal bleeding, ileus, thrombocytopenia, septicemia, pyohemia, hemorrhage/seroma/hematoma, wound infection, nerve injuries, and wound rupture/not healing.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eUnivariable analysis was used to evaluate all potential variables associated with BT. Chi-squared and Wilcoxon rank test were applied to compare categorical variables and continuous variables respectively. Binary logistic regression analysis with stepwise regression was conducted to identify independent risk factors for BT subsequent to LSS and to examine the correlation of BT with other medical and surgical complications.\u003c/p\u003e \u003cp\u003eThe regression analysis in this study simultaneously included all variables pre-established by the NIS, such as demographics, hospital setting, and preoperative comorbidities (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The use of an alpha level of P\u0026thinsp;\u0026le;\u0026thinsp;0.001 was chosen to indicate statistical significance due to the substantial sample size, a practice that has been employed in earlier investigations using the NIS database [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. All statistical analyses were performed using the SPSS statistical software package (Version 26.0.0; SPSS, Inc., Chicago, IL).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eVariables entered into the binary logistic regression analysis\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables Categories\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSpecific Variables\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePatient demographics\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAge (\u0026le;\u0026thinsp;64 years and \u0026ge;\u0026thinsp;65 years), sex (male and female), race (White, Black, Hispanic, Asian or Pacific Islander, Native American and Other)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eHospital characteristics\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eType of admission (non-elective, elective), bed size of hospital (small, medium, large), teaching status of hospital (nonteaching, teaching), location of hospital (rural, urban), type of insurance (Medicare, Medicaid, private insurance, self-pay, no charge, other), location of the hospital (northeast, Midwest or north central, south, west)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eComorbidities\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAIDS, alcohol abuse, deficiency anemia, rheumatoid diseases/collagen vascular diseases, chronic blood loss anemia, congestive heart failure, chronic pulmonary disease, coagulopathy, depression, diabetes (uncomplicated), diabetes (with chronic complications), drug abuse, hypertension, hypothyroidism, liver disease, lymphoma, fluid and electrolyte disorders, metastatic cancer, other neurological disorders, obesity, paralysis, peripheral vascular disorders, psychoses, pulmonary circulation disorders, renal failure, solid tumor without metastasis, valvular disease, weight loss, and peptic ulcer disease excluding bleeding\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"2\"\u003eAIDS: Acquired immunodeficiency syndrome\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eIncidence of BT in patients undergoing LD and LF\u003c/h2\u003e \u003cp\u003eThis study included a total of 931,789 patients who had undergone LD or LF surgery from 2010 to 2019. This cohort was composed primarily of no BT (n\u0026thinsp;=\u0026thinsp;863,873; 92.7%) and BT (n\u0026thinsp;=\u0026thinsp;67,916; 7.3%) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The rate of BT generally decreased from 8.6% in 2010 to 5.0% in 2019 (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePatient characteristics and outcomes of BT after LSS (2010\u0026ndash;2019)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eCharacteristics\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo transfusion\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eTransfusion\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eP\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTotal (n\u0026thinsp;=\u0026thinsp;count)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e863,873\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e67,916\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTotal incidence (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e7.3%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAge (median, years)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e59 (47\u0026ndash;69)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e63 (52\u0026ndash;72)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAge group (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18\u0026ndash;44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17.8%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e10.0%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e45\u0026ndash;64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e44.3%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e36.6%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e65\u0026ndash;74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23.7%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e28.5%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12.1%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17.2%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eGender (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e48.7%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e39.7%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFemale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e51.3%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e60.3%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRace (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWhite\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e81.1%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e77.1%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"5\" rowspan=\"6\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBlack\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8.2%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e9.8%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHispanic\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.4%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7.2%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAsian or Pacific Islander\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.3%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.0%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNative American\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.5%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.5%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOther\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.6%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.4%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eNumber of Comorbidity (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.0%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.6%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.4%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.4%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.4%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e88.0%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e96.2%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLOS (median, d)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (1\u0026ndash;4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5 (4\u0026ndash;8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTOTCHG (median, $)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e71,359 (40,006-122,035)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e142,839 (87,665\u0026thinsp;\u0026minus;\u0026thinsp;234,450)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eType of insure (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMedicare\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e39.5%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e48.5%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"5\" rowspan=\"6\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMedicaid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.5%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.1%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePrivate insurance\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e42.9%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e35.6%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSelf-pay\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.4%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.4%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNo charge\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.2%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.1%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOther\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8.5%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.4%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBed size of hospital (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSmall\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17.8%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e18.2%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e0.035\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMedium\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24.5%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e24.2%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLarge\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e57.6%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e57.6%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eElective admission (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e85%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e78%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eType of hospital (teaching %)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e53.7%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e57.6%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRegion of hospital (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNortheast\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e16.2%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17.3%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMidwest or North Central\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22.9%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e20.3%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSouth\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e39.9%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e40.3%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWest\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21.0%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e22.2%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eLocation of hospital (urban, %)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e94.4%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e95.9%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eDied (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.2%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.9%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eBT: Blood transfusion, LLS: Lumbar spinal surgery, LOS: Length of stay, TOTCHG: Total charge\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eThe characteristics in patient demographics and hospital factors between the two surgery groups\u003c/h3\u003e\n\u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e describes the baseline characteristics (demographics and hospital characteristics) between two groups. Patients receiving BT were relatively older (63 years vs. 59 years, P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001). Consistently, a significant difference was observed in the age distribution between two groups, with a higher proportion of patients aged 75 years and older in the blood transfusion group (17.2% vs. 12.1%, P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eA, B). Patients with BT requirements were 9% more likely to be female (60.3% vs 51.3%, P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Additionally, the race distribution between the two groups differed, with the Black demonstrating larger proportions in the transfusion group (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, and Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eC, D). As expected, teaching and urban hospitals demonstrated a higher BT incidence following LSS (P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001). Regarding to geographical location, perioperative BT more likely occurred in the Northeast and West, whereas less likely occurred in the Midwest or North Central regions (P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). No significant difference was observed in terms of bed size of hospital.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eAdverse outcomes of BT after LSS\u003c/h2\u003e \u003cp\u003eNot surprisingly, patients undergoing LSS with multiple preoperative comorbidities (n\u0026thinsp;\u0026ge;\u0026thinsp;3) exhibited a 8.2% higher incidence of BT (96.2% vs. 88.0%, P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eE, F). Correspondingly, inpatients mortality following LSS was significantly higher in those receiving BT (0.9% vs. 0.2%, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Therefore, these resulted in increased length of stay (LOS) and total charge (TOTCHG) for transfused patients. Median LOS increased from 3 days to 5 days (P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), and median TOTCHG increased from \u003cspan\u003e$\u003c/span\u003e71,359 to \u003cspan\u003e$\u003c/span\u003e142,839 (P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001). Additionally, patients receiving BT were less likely to be electively admitted to hospital (78% vs. 85%, P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eRisk factors related to BT after LSS\u003c/h2\u003e \u003cp\u003eUnivariate analysis revealed that the prevalence of alcohol abuse (0.1%), deficiency anemia (16.8%), rheumatoid arthritis/collagen vascular diseases (5.2%), chronic blood loss anemia (2.1%), congestive heart failure (4.8%), coagulopathy (9.2%), depression (17.1%), drug abuse (2.7%), hypothyroidism (14.6%), lymphoma (0.8%), fluid and electrolyte disorders (23.9%), metastatic cancer (2.3%), other neurological disorders (6.8%), obesity (17.9%), paralysis (7.1%), peripheral vascular disorders (4.5%), psychoses (3.9%), pulmonary circulation disorders (2.1%), renal failure (7.8%), solid tumor without metastasis (1.3%), valvular disease (4.2%), weight loss (4.1%) and diabetes with chronic complications (5.4%) was significantly higher among patients receiving BTs after LSS (P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001). (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eRisk factors associated with BT after LSS\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c2\" namest=\"c1\" rowspan=\"2\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003eMultivariate Logistic Regression\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eOR\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e95% CI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eP\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAge\u0026thinsp;\u0026ge;\u0026thinsp;65 years old\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.332\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.267-1.400\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eFemale\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.466\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.462\u0026ndash;1.514\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRace\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWhite\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRef\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eBlack\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.703\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.638\u0026ndash;0.775\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHispanic\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.741\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.664\u0026ndash;0.827\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAsian or Pacific Islander\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.696\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.616\u0026ndash;0.786\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNative American\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.862\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.709\u0026ndash;1.048\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.137\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOther\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.026\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.800-1.318\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.838\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eType of insurance\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMedicare\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRef\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMedicaid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.985\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.913\u0026ndash;1.063\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.701\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePrivate insurance\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.037\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.948\u0026ndash;1.134\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.430\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSelf-pay\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.978\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.914\u0026ndash;1.045\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.508\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNo charge\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.929\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.804\u0026ndash;1.075\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.324\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOther\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.696\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.475\u0026ndash;1.020\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.063\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBed size of hospital\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSmall\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRef\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMedium\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.952\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.906\u0026ndash;1.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.053\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLarge\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.279\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.230\u0026ndash;1.330\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eElective admission\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.099\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.052\u0026ndash;1.148\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.002\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTeaching hospital\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.111\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.073\u0026ndash;1.150\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eUrban hospital\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.207\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.114\u0026ndash;1.307\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRegion of hospital\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNortheast\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRef\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMidwest or North Central\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.986\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.935\u0026ndash;1.050\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.655\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSouth\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.041\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.979\u0026ndash;1.108\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.200\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWest\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.155\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.094\u0026ndash;1.218\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eBT: Blood transfusion, LLS: Lumbar spinal surgery\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eLogistic regression analysis was used to investigate the risk factors associated with BT after LSS (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e), and the final indicators were determined as follows: for patient demographics and hospital characteristics, it was found that age\u0026thinsp;\u0026ge;\u0026thinsp;65 years old (odds ratio [OR]\u0026thinsp;=\u0026thinsp;1.332; 95% confidence interval [CI]\u0026thinsp;=\u0026thinsp;1.267-1.400; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), female (OR\u0026thinsp;=\u0026thinsp;1.466; CI\u0026thinsp;=\u0026thinsp;1.462\u0026ndash;1.514; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), large bed size of hospital (OR\u0026thinsp;=\u0026thinsp;1.279; CI\u0026thinsp;=\u0026thinsp;1.230\u0026ndash;1.330; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), elective admission (OR\u0026thinsp;=\u0026thinsp;1.099; CI\u0026thinsp;=\u0026thinsp;1.052\u0026ndash;1.148; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), teaching hospital (OR\u0026thinsp;=\u0026thinsp;1.111; CI\u0026thinsp;=\u0026thinsp;1.073\u0026ndash;1.150; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), urban hospital (OR\u0026thinsp;=\u0026thinsp;1.207; CI\u0026thinsp;=\u0026thinsp;1.114\u0026ndash;1.307; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) to be risk factors for BT after LSS. Interestingly, we additionally found that being black (OR\u0026thinsp;=\u0026thinsp;0.703; CI\u0026thinsp;=\u0026thinsp;0.638\u0026ndash;0.775; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), Hispanic (OR\u0026thinsp;=\u0026thinsp;0.741; CI\u0026thinsp;=\u0026thinsp;0.664\u0026ndash;0.827; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) and Asian or Pacific Islander (OR\u0026thinsp;=\u0026thinsp;0.696; CI\u0026thinsp;=\u0026thinsp;0.616\u0026ndash;0.786; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) were protective factors.\u003c/p\u003e \u003cp\u003eRegarding comorbidities, we ultimately identified alcohol abuse (OR\u0026thinsp;=\u0026thinsp;1.247; CI\u0026thinsp;=\u0026thinsp;1.112\u0026ndash;1.399; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), deficiency anemia (OR\u0026thinsp;=\u0026thinsp;2.720; CI\u0026thinsp;=\u0026thinsp;2.598\u0026ndash;2.847; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), rheumatoid diseases/collagen vascular diseases (OR\u0026thinsp;=\u0026thinsp;1.206; CI\u0026thinsp;=\u0026thinsp;1.115\u0026ndash;1.304; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), chronic blood loss anemia (OR\u0026thinsp;=\u0026thinsp;5.765; CI\u0026thinsp;=\u0026thinsp;5.082\u0026ndash;6.539; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), congestive heart failure (OR\u0026thinsp;=\u0026thinsp;1.318; CI\u0026thinsp;=\u0026thinsp;1.202\u0026ndash;1.446; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), coagulopathy (OR\u0026thinsp;=\u0026thinsp;3.560; CI\u0026thinsp;=\u0026thinsp;3.300-3.841; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), depression (OR\u0026thinsp;=\u0026thinsp;1.131; CI\u0026thinsp;=\u0026thinsp;1.081\u0026ndash;1.183; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), drug abuse (OR\u0026thinsp;=\u0026thinsp;1.339; CI\u0026thinsp;=\u0026thinsp;1.180\u0026ndash;1.520; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), hypothyroidism (OR\u0026thinsp;=\u0026thinsp;1.093; CI\u0026thinsp;=\u0026thinsp;1.040\u0026ndash;1.148; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), lymphoma (OR\u0026thinsp;=\u0026thinsp;2.029; CI\u0026thinsp;=\u0026thinsp;1.652\u0026ndash;2.493; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), fluid and electrolyte disorders (OR\u0026thinsp;=\u0026thinsp;2.530; CI\u0026thinsp;=\u0026thinsp;2.418\u0026ndash;2.648; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), metastatic cancer (OR\u0026thinsp;=\u0026thinsp;2.312; CI\u0026thinsp;=\u0026thinsp;2.017\u0026ndash;2.649; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), other neurological disorders (OR\u0026thinsp;=\u0026thinsp;1.231; CI\u0026thinsp;=\u0026thinsp;1.148\u0026ndash;1.320; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), obesity (OR\u0026thinsp;=\u0026thinsp;1.118; CI\u0026thinsp;=\u0026thinsp;1.067\u0026ndash;1.173; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), paralysis (OR\u0026thinsp;=\u0026thinsp;1.526; CI\u0026thinsp;=\u0026thinsp;1.413\u0026ndash;1.649; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), peripheral vascular disorders (OR\u0026thinsp;=\u0026thinsp;1.347; CI\u0026thinsp;=\u0026thinsp;1.232\u0026ndash;1.473; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), psychoses (OR\u0026thinsp;=\u0026thinsp;1.183; CI\u0026thinsp;=\u0026thinsp;1.078\u0026ndash;1.297; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), pulmonary circulation disorders (OR\u0026thinsp;=\u0026thinsp;1.506; CI\u0026thinsp;=\u0026thinsp;1.317\u0026ndash;1.722; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), renal failure (OR\u0026thinsp;=\u0026thinsp;1.324; CI\u0026thinsp;=\u0026thinsp;1.222\u0026ndash;1.435; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), solid tumor without metastasis (OR\u0026thinsp;=\u0026thinsp;1.444; CI\u0026thinsp;=\u0026thinsp;1.197\u0026ndash;1.742; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), valvular disease (OR\u0026thinsp;=\u0026thinsp;1.332; CI\u0026thinsp;=\u0026thinsp;1.222\u0026ndash;1.452; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) and weight loss (OR\u0026thinsp;=\u0026thinsp;1.545; CI\u0026thinsp;=\u0026thinsp;1.387\u0026ndash;1.722; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) as risk factors for BT after LSS (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eRelationship between BT and preoperative comorbidities\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c2\" namest=\"c1\" rowspan=\"2\"\u003e \u003cp\u003eComorbidities\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003eUnivariate Analysis\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003eMultivariate Logistic Regression\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo transfusion\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eTransfusion\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eP\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eOR\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e95% CI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eP\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003ePreoperative comorbidities\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAcquired immune deficiency syndrome\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1034 (0.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e95 (0.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.145\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.190\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.713\u0026ndash;1.987\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.506\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAlcohol abuse\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13,425 (1.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1798 (2.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.336\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.203\u0026ndash;1.485\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDeficiency anemia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e40,124 (4.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e11,397 (16.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.724\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.611\u0026ndash;2.842\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRheumatoid arthritis/collagen vascular diseases\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e29,302 (3.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3553 (5.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.263\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.175\u0026ndash;1.358\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eChronic blood loss anemia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3189 (0.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1452 (2.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.806\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.151\u0026ndash;6.544\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCongestive heart failure\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17,689 (2.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3229 (4.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.318\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.209\u0026ndash;1.438\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eChronic pulmonary disease\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e135,318 (15.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e12,461 (18.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.963\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.924\u0026ndash;1.003\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.072\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCoagulopathy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e14,044 (1.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6244 (9.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.455\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.216\u0026ndash;3.712\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDepression\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e126,350 (14.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e11,611 (17.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.166\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.117\u0026ndash;1.217\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDiabetes, uncomplicated\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e133,996 (15.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e11,193 (16.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.941\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.902\u0026ndash;0.982\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.005\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDrug abuse\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e14,114 (1.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1830 (2.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.557\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.393\u0026ndash;1.741\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHypertension\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e443,579 (51.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e39,066 (57.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.046\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.010\u0026ndash;1.084\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.012\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHypothyroidism\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e95,798 (11.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e9907 (14.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.091\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.041\u0026ndash;1.142\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLiver disease\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11,813 (1.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1716 (2.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.189\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.052\u0026ndash;1.343\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.005\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLymphoma\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2356 (0.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e563 (0.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.989\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.633\u0026ndash;2.389\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFluid and electrolyte disorders\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e62,114 (7.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e16,232 (23.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.454\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.351\u0026ndash;2.561\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMetastatic cancer\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4796 (0.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1550 (2.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.479\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.189\u0026ndash;2.807\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOther neurological disorders\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e31,359 (3.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4621 (6.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.175\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.100-1.255\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eObesity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e139,402 (16.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e12,128 (17.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.196\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.144\u0026ndash;1.249\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eParalysis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25,478 (2.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4816 (7.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.399\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.303\u0026ndash;1.502\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePeripheral vascular disorders\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e20,946 (2.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3051 (4.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.336\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.230\u0026ndash;1.451\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePsychoses\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23,974 (2.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2654 (3.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.329\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.224\u0026ndash;1.443\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePulmonary circulation disorders\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5420 (0.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1435 (2.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.546\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.362\u0026ndash;1.755\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRenal failure\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30,346 (3.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5279 (7.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.293\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.201\u0026ndash;1.393\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSolid tumor without metastasis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4795 (0.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e898 (1.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.595\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.351\u0026ndash;1.885\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eValvular disease\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e19,497 (2.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2884 (4.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.296\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.195\u0026ndash;1.406\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWeight loss\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7897 (0.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2793 (4.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.645\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.488\u0026ndash;1.819\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePeptic ulcer disease excluding bleeding\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e731 (0.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e90 (0.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.874\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.544\u0026ndash;9.722\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.004\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"8\"\u003eBT: Blood transfusion, OR: Odds ratio, CI: Confidence interval\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eCorrelation analysis between BT and postoperative complications\u003c/h2\u003e \u003cp\u003eIn terms of postoperative complications, patients receiving perioperative BT were found to have higher incidence of complications including: acute myocardial infarction (1.8%), postoperative shock (0.6%), acute heart failure (4.0%), acute renal failure (7.1%), urinary tract infection (7.5%), urinary retention (7.4%), pneumonia (4.6%), continuous trauma ventilation (5.1%), respiratory failure (3.8%), pulmonary embolism (1.1%), deep vein thrombosis (2.0%), stroke (1.8%), postoperative delirium (3.0%), gastrointestinal bleeding (0.5%), ileus (5.4%), thrombocytopenia (7.2%), septicemia (3.2%), hemorrhage/seroma/hematoma (3.6%), wound infection (1.3%), nerve injuries (4.3%), and wound rupture/not healing (0.7%) (P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eRelationship between BT and postoperative complications\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c2\" namest=\"c1\" rowspan=\"2\"\u003e \u003cp\u003eComplications\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003eUnivariate Analysis\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003eMultivariate Logistic Regression\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo transfusion\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eTransfusion\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eP\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eOR\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e95% CI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eP\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eMedical complications\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAcute myocardial infarction\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3953 (0.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1223 (1.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.926\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.790\u0026ndash;2.073\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCardiac arrest\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e969 (0.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e277 (0.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.589\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.504\u0026ndash;0.609\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePostoperative shock\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e531 (0.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e407 (0.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.016\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.592\u0026ndash;3.509\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAcute heart failure\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e14,133 (1.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2739 (4.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.549\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.480\u0026ndash;1.622\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAcute renal failure\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e15,824 (1.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4851 (7.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.262\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.188\u0026ndash;1.341\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eUrinary tract infection\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23,581 (2.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5067 (7.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.192\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.130\u0026ndash;1.259\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eUrinary retention\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e37,393 (4.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5021 (7.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.262\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.221\u0026ndash;1.304\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eContinuous trauma ventilation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8443 (1.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3468 (5.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.160\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.052\u0026ndash;2.274\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePneumonia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10,292 (1.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3110 (4.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.241\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.179\u0026ndash;1.306\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRespiratory failure\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7858 (0.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2596 (3.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.458\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.379\u0026ndash;1.541\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePulmonary embolism\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2285 (0.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e756 (1.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.580\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.437\u0026ndash;1.737\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDeep vein thrombosis\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4025 (0.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1373 (2.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.609\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.498\u0026ndash;1.728\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eStroke\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6953 (0.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1227 (1.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.118\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.933\u0026ndash;1.341\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.228\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePostoperative delirium\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7126 (0.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2052 (3.0%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.143\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.030\u0026ndash;2.262\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGastrointestinal bleeding\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e703 (0.1%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e338 (0.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.954\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.684\u0026ndash;2.268\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eIleus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e14,782 (1.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3669 (5.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.180\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.088\u0026ndash;2.276\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eThrombocytopenia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10,669 (1.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4916 (7.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e4.244\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.089\u0026ndash;4.405\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSepticemia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5927 (0.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2180 (3.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.365\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.488\u0026ndash;3.823\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.553\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSurgical complications\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHemorrhage/seroma/hematoma\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7378 (0.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2431 (3.6%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.777\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.639\u0026ndash;2.923\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWound infection\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3821 (0.4%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e889 (1.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.374\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.263\u0026ndash;1.496\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNerve injuries\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25,427 (2.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2907 (4.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.255\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.204\u0026ndash;1.307\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWound rupture/not healing\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1744 (0.2%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e471 (0.7%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.331\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.183\u0026ndash;1.498\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;0.0001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"8\"\u003eBT: Blood transfusion, OR: Odds ratio, CI: Confidence interval\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eIn multivariate analysis, BT was associated with acute myocardial infarction (OR\u0026thinsp;=\u0026thinsp;1.926; CI\u0026thinsp;=\u0026thinsp;1.790\u0026ndash;2.073), postoperative shock (OR\u0026thinsp;=\u0026thinsp;3.016; CI\u0026thinsp;=\u0026thinsp;2.592\u0026ndash;3.509), acute heart failure (OR\u0026thinsp;=\u0026thinsp;1.926; CI\u0026thinsp;=\u0026thinsp;1.790\u0026ndash;2.073), acute renal failure (OR\u0026thinsp;=\u0026thinsp;1.262; CI\u0026thinsp;=\u0026thinsp;1.188\u0026ndash;1.341), urinary tract infection (OR\u0026thinsp;=\u0026thinsp;1.192; CI\u0026thinsp;=\u0026thinsp;1.130\u0026ndash;1.259), urinary retention (OR\u0026thinsp;=\u0026thinsp;1.262; CI\u0026thinsp;=\u0026thinsp;1.221\u0026ndash;1.304), continuous trauma ventilation (OR\u0026thinsp;=\u0026thinsp;2.160; CI\u0026thinsp;=\u0026thinsp;2.052\u0026ndash;2.274), pneumonia (OR\u0026thinsp;=\u0026thinsp;1.241; CI\u0026thinsp;=\u0026thinsp;1.179\u0026ndash;1.306), respiratory failure (OR\u0026thinsp;=\u0026thinsp;1.458; CI\u0026thinsp;=\u0026thinsp;1.379\u0026ndash;1.541), pulmonary embolism (OR\u0026thinsp;=\u0026thinsp;1.580; CI\u0026thinsp;=\u0026thinsp;1.437\u0026ndash;1.737), deep vein thrombosis (OR\u0026thinsp;=\u0026thinsp;1.609; CI\u0026thinsp;=\u0026thinsp;1.498\u0026ndash;1.728), postoperative delirium (OR\u0026thinsp;=\u0026thinsp;2.143; CI\u0026thinsp;=\u0026thinsp;2.030\u0026ndash;2.262), gastrointestinal bleeding (OR\u0026thinsp;=\u0026thinsp;1.954; CI\u0026thinsp;=\u0026thinsp;1.684\u0026ndash;2.268), ileus (OR\u0026thinsp;=\u0026thinsp;2.180; CI\u0026thinsp;=\u0026thinsp;2.088\u0026ndash;2.276), thrombocytopenia (OR\u0026thinsp;=\u0026thinsp;4.244; CI\u0026thinsp;=\u0026thinsp;4.089\u0026ndash;4.405), hemorrhage/seroma/hematoma (OR\u0026thinsp;=\u0026thinsp;2.777; CI\u0026thinsp;=\u0026thinsp;2.639\u0026ndash;2.923), wound infection (OR\u0026thinsp;=\u0026thinsp;1.374; CI\u0026thinsp;=\u0026thinsp;1.263\u0026ndash;1.496), nerve injuries (OR\u0026thinsp;=\u0026thinsp;1.255; CI\u0026thinsp;=\u0026thinsp;1.204\u0026ndash;1.307), and wound rupture/not healing (OR\u0026thinsp;=\u0026thinsp;1.331; CI\u0026thinsp;=\u0026thinsp;1.183\u0026ndash;1.498; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study demonstrates a national health-economic investigation of patients receiving perioperative BT after LSS. Given the improvement of component design, progress in surgical techniques [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], striction of transfusion managements [\u003cspan additionalcitationids=\"CR24\" citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e], there was a reduction of BT incidence from 2010 to 2019 generally (from 8.6 to 5.0%) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Importantly, this finding has not been reported to date. Although transfusion rate decreased annually, the overall transfusion rate in the patients undergoing LSS remained high. Consequently, it is essential to investigate the risk factors associated with BT in LSS for more effective management.\u003c/p\u003e \u003cp\u003eNotably, patients with BT requirement undergoing LSS accompanied with adverse clinical outcomes such as more comorbidities, extended LOS, increased total charge, and elevated inpatient mortality, which further emphasize the necessity to explore the risk factors associated with BT.\u003c/p\u003e \u003cp\u003eOur study found that advanced age and female gender were associated with a high risk of postoperative blood transfusion after LSS. In demographic analysis, patients receiving BT were 4 years older than those without. Additionally, the age distribution revealed that elderly patients (\u0026ge;\u0026thinsp;65 years) occupied a greater proportion in the BT group. Moreover, the logistic regression analysis demonstrated that aged over 65 years and females were risk factors for BT after LSS (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). A potential reason is that elderly individuals with decreased bone marrow function, hematopoietic capacity, and physiological reserve [\u003cspan additionalcitationids=\"CR27\" citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. Female patients often exhibit lower baseline hemoglobin levels compared to male patients probably due to the variations in hormonal levels and a greater prevalence of iron deficiency anemia resulting from menstrual blood loss [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. One possible explanation accounting for teaching hospital and urban hospital as risk factors associated with perioperative BT (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eA, B, C, and D) is that patients in these institutions are commonly challenging with complex surgeries and more comorbidities [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eDeficiency anemia, chronic blood loss anemia, and coagulopathy were identified as risk factors for BT in the present study, which was met our expectations (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eE and F). This is possibly correlated with lower preoperative hemoglobin levels in these patients. Preoperative coagulation dysfunction may contribute to substantial intraoperative blood loss, necessitating perioperative transfusion [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. Additionally, cardiovascular diseases including congestive heart failure, valvular disease, peripheral vascular disease, pulmonary circulation disorders, and hypertension can lead to organ hypoxia, ischemia, and inadequate blood volume, thereby increasing the likelihood of transfusion. Furthermore, comorbidities such as diabetes with chronic complications, rheumatoid arthritis/collagen vascular diseases, and hypothyroidism were confirmed as risk factors of BT. These diseases are either systemic autoimmune disorders or strongly associated with systemic autoimmune disorders, elevating the likelihood of preoperative anemia and low protein levels [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. Moreover, lymphoma, solid tumor without metastasis, metastatic cancer, liver disease, paralysis, peptic ulcer disease excluding bleeding, fluid and electrolyte disorders, obesity, and weight loss were also found to be risk factors of BT in this study,which may be attributed to that patients with these consumptive or malnourished comorbidities commonly experience low hematopoietic capacity, preoperative anemia, or extra blood loss [\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]. A possible explanation for chronic renal failure as a risk factor may be that it reduces the efficiency of red blood cell production and red blood cell lifespan, leading to anemia and consequently necessitating transfusion [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. In addition, alcohol abuse, depression, psychoses, drug abuse, and other neurological disorders were identified as independent risk factors for requiring BT after LSS.\u003c/p\u003e \u003cp\u003eAfter transfusion, there is an increased likelihood of acute renal failure, possibly due to that the BT may increase in circulating free iron and exacerbating perioperative stress injury, which is associated with renal organ damage [\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e]. As previously mentioned, chronic renal failure is one of the risk factors associated with BT. Therefore, a plausible explanation may be that BT has a strong correlation with kidney damage. Moreover, BT is associated with acute myocardial infarction, acute heart failure, deep vein thrombosis, and thrombocytopenia. Changes in blood viscosity may lead to thrombosis, increased circulatory volume, and subsequent cardiac strain [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e]. In patients with acute myocardial infarction, persistently elevated hemoglobin levels may improve clinical outcomes by increasing oxygen delivery to the myocardium, potentially contributing to the occurrence of transfusion [\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e]. Although thrombocytopenia is not a common complication of transfusion, the possibility of transfusion-related thrombocytopenia cannot be ruled out in massive transfusion [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e]. Conversely, as mentioned earlier, cardiovascular diseases such as chronic heart failure are also risk factors for BT. Our study also indicates that BT after LSS is associated with perioperative infectious complications, including septicemia, pneumonia, wound infections, hemorrhage/seroma/hematoma, wound rupture/not healing, and urinary tract infection. The impact of BT on infectious complications may be related to blood processing methods, blood storage techniques, and bacterial contamination [\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e]. Patients with infections are more likely to receive transfusions, possibly because infections result in greater circulatory dysfunction, predispose to anemia and transfusion [\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e]. Therefore, it was found that the aforementioned complications and BT are associated, but causality cannot be proven clearly. Due to methodological limitations of observational and database studies, inferring causality between transfusion and adverse outcomes remains challenging.\u003c/p\u003e \u003cp\u003eIn summary, BT was associated with numerous comorbidities and complications (Figs.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e and \u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e). Patients with certain comorbidities may have a higher risk of transfusion during the perioperative period due to the baseline anemia, and certain related complications may adversely affect perioperative patients. Therefore, developing strategies to reduce the need for BT remains important for orthopedic surgeons to minimize avoidable risks. By identifying high-risk patients, perioperative management can be optimized and more informed patient counseling can occur before surgery. Many interventions have demonstrated efficacy in mitigating blood loss and minimizing the necessity for transfusions. These interventions encompass the augmented utilization of spinal anesthesia, administration of tranexamic acid, implementation of blood management protocols that do not rely on stringent transfusion triggers, adoption of less aggressive chemical anticoagulants, and utilization of hemostatic agents [\u003cspan additionalcitationids=\"CR43 CR44\" citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e]. By employing these interventions, it is possible to effectively diminish both blood loss and the need for transfusions.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eGiven that this study utilizes the NIS database, there are some limitations. Initially, it should be noted that the NIS database only captures patient information prior to discharge. Consequently, any post-discharge issues are not accounted for in the database. The analysis of solely early medical records introduces a potential constraint that could result in an underestimation of the occurrence of transfusions. Secondly, the NIS does not include detailed clinical information such as the type of anesthesia used, amount of blood loss, perioperative hemoglobin values, and the number or volume of transfusion units, but it does not affect the analysis of risk factors directly. Furthermore, due to the lack of other risk variables in the NIS database, our analysis was limited to the risk factors recorded in this database. Another limitation is that the most recent data are from 2019, which may not fully explain recent changes in transfusion rates. Additionally, the etiology associated with the results obtained from this retrospective database analysis requires further validation.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eBT is a common complication after LSS, especially in the elderly and women, with an overall incidence rate of 7.3%. The yearly occurrence of BT following LSS exhibited a decline tendency from 2010 to 2019. This study identified several risk factors, including advanced age (\u0026ge;\u0026thinsp;65 years), female, large bed size of hospital, elective admission, teaching hospital, urban hospital, alcohol abuse, deficiency anemia, rheumatoid diseases/collagen vascular diseases, chronic blood loss anemia, congestive heart failure, coagulopathy, depression, drug abuse, hypothyroidism, lymphoma, fluid and electrolyte disorders, metastatic cancer, other neurological disorders, obesity, paralysis, peripheral vascular disorders, psychoses, pulmonary circulation disorders, renal failure, solid tumor without metastasis, valvular disease and weight loss. Additionally, the occurrence of BT was correlated with an increased length of hospital stay (LOS), TOTCHG and mortality. Moreover, BT was associated with urinary tract infection, thrombocytopenia, acute renal failure, pneumonia, gastrointestinal complication, DVT, genitourinary disease, PE, AMI, peripheral vascular disease, respiratory disease, postoperative delirium, postoperative shock, GI bleeding, chest pain, ileus, urinary retention, respiratory failure, continuous trauma ventilation, arrhythmia, heart failure, hemorrhage/seroma/hematoma, wound infection, lower nerve injuries, and wound rupture/not healing. By identifying high-risk patients, surgeons can counsel patients better and optimize management to reduce the requirement of BTs.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003eLSS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003eLumbar spinal surgery\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003eLD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003eLumbar decompression\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003eLF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003eLumbar fusion\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003eLIF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003eLumbar interbody fusion\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003eALIF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003eAnterior lumbar interbody fusion\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003ePLIF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003ePosterior lumbar interbody fusion\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003eTLIF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003eTransforaminal lumbar interbody fusion\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003eBT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003eBlood transfusion\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003ePR-ABT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003ePredonated autologous blood transfusion\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003ePEABT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003ePerioperative autologous blood transfusion\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003eALBT\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003eAllogeneic blood transfusion\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003eTHA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003eTotal hip arthroplasty\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003eNIS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003eNationwide Inpatient Sample\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003eLOS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003eLength of stay\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003eTOTCHG\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003eTotal charge\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003eOR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003eOdds ratio\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20.666666666666668%\" valign=\"top\"\u003e\n \u003cp\u003eCI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"79.33333333333333%\" valign=\"top\"\u003e\n \u003cp\u003eConfidence interval\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets are available at https://www.ahrq.gov/data/hcup/index.html.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by the President Foundation of Nanfang Hospital, Southern Medical University [2021]33 and the Guangdong Provincial Department of Education [2021]29.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eYH and JW designed the study; YH, CW, and ZH performed this study, analyzed and interpreted data; ZH carried out data collection; and CW wrote the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eGoz V, Weinreb JH, McCarthy I, Schwab F, Lafage V, Errico TJ. Perioperative complications and mortality after spinal fusions: analysis of trends and risk factors. Spine (Phila Pa 1976). 2013;38(22):1970\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRajaee SS, Bae HW, Kanim LE, Delamarter RB. Spinal fusion in the United States: analysis of trends from 1998 to 2008. Spine (Phila Pa 1976). 2012;37(1):67\u0026ndash;76.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDeyo RA, Mirza SK, Martin BI, Kreuter W, Goodman DC, Jarvik JG. Trends, major medical complications, and charges associated with surgery for lumbar spinal stenosis in older adults. 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Patient Blood Management During Lumbar Spinal Fusion Surgery. World Neurosurg. 2019;130:e566\u0026ndash;72.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLentschener C, Cottin P, Bouaziz H, Mercier FJ, Wolf M, Aljabi Y, Boyer-Neumann C, Benhamou D. Reduction of blood loss and transfusion requirement by aprotinin in posterior lumbar spine fusion. Anesth Analg. 1999;89(3):590\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Lumbar spinal surgery, lumbar decompression, lumbar fusion, blood transfusion, risk factors, Nationwide Inpatient Sample","lastPublishedDoi":"10.21203/rs.3.rs-4529636/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4529636/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eBlood transfusion is a frequently observed complication subsequent to lumbar spinal surgery (LSS), which may potentially result in a range of unfavorable consequences. However, a related large-scale multi-center analysis has not been conducted thus far.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eA retrospective database analysis was performed using the Nationwide Inpatient Sample, which is the largest comprehensive hospital care database in the United States. The analysis included the data from 2010 to 2019, evaluating the patient's demographic characteristics, health system data, comorbidities, and medical and surgical issues during the perioperative process.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThere were 931,789 patients undergoing LSS..The overall incidence rate of blood transfusion was found to be 7.3%, generally decreasing from 8.6% in 2010 to 5.0% in 2019. Patients undergoing LSS with blood transfusions exhibited a higher prevalence of comorbidities, prolonged length of stay, increased total hospitalization costs, and elevated in-hospital mortality rates. These patients were associated with complications including thrombocytopenia, acute renal failure, deep venous thrombosis, pulmonary embolism, acute myocardial infarction, peripheral vascular disease, postoperative shock, gastrointestinal bleeding, chest pain, respiratory failure, heart failure, hemorrhage, and wound infection. Risk factors associated with blood transfusion included advanced age (\u0026ge;\u0026thinsp;65 years), female, alcohol abuse, deficiency anemia, rheumatoid diseases, chronic blood loss anemia, congestive heart failure, coagulopathy, metastatic cancer, obesity, peripheral vascular disorders, chronic renal failure, solid tumor without metastasis, valvular disease.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eBlood transfusion emerges as a frequent complication following LSS and several risk factors were identified, which will help ensure safe management of postoperative patients and improve outcomes. Clinicians should pay more attention to these factors, thereby improving perioperative management.\u003c/p\u003e","manuscriptTitle":"A retrospective analysis: incidence and risk factors of blood transfusion after lumbar spinal surgery","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-07-13 02:14:24","doi":"10.21203/rs.3.rs-4529636/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"1c0a47da-a173-4149-a75b-c77d8e16b286","owner":[],"postedDate":"July 13th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-10-03T03:38:14+00:00","versionOfRecord":[],"versionCreatedAt":"2024-07-13 02:14:24","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4529636","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4529636","identity":"rs-4529636","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}