The Effect of Body Mass Index on Short-term Outcomes in Patients Undergoing Off-pump Coronary Artery Bypass Grafting Surgery: A Retrospective Study from a Single Cardiovascular Center

The Effect of Body Mass Index on Short-term Outcomes in Patients Undergoing Off-pump Coronary Artery Bypass Grafting Surgery: A Retrospective Study from a Single Cardiovascular Center | 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 The Effect of Body Mass Index on Short-term Outcomes in Patients Undergoing Off-pump Coronary Artery Bypass Grafting Surgery: A Retrospective Study from a Single Cardiovascular Center Chen ying Ding, Wen hui Qi, Yujie An, Yun-tai Yao This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3240589/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 11 Feb, 2024 Read the published version in Journal of Cardiothoracic Surgery → Version 1 posted 8 You are reading this latest preprint version Abstract Objective This study is designed to investigate the impact of body mass index (BMI) on the short-term outcomes of patients undergoing off-pump coronary artery bypass graft (OPCAB) surgery. Methods Data was obtained from 1006 Chinese patients who underwent isolated, primary OPCAB at a high-traffic cardiovascular center during 2020. Subjects were categorized, by BMI, into a low-normal weight (LN) group (BMI < 24 kg/m 2 ), an overweight (OVW) group (24 ≤ BMI < 28 kg/m 2 ), and an obese (OBS) group (BMI ≥ 28 kg/m 2 ). Information pertaining to patients’ short-term outcomes (including incidence of mortality and morbidities; duration of postoperative mechanical ventilation; length of stay in the ICU and hospital; postoperative bleeding; etc .) were extracted, and the data from each group were compared. Results The incidences of in-hospital mortality and morbidities were similar for all three groups. The volume of fluid infusion, postoperative bleeding within 24 h and total bleeding in LN group were higher than those in the OBS group ( P < 0.001). The hemoglobin level was lower in the LN group than that in the OBS group ( P < 0.001). Duration of mechanical ventilation and length of stay in the ICU in the LN group were longer than those in the OBS group ( P < 0.001). Conclusions Our results demonstrate that BMI is not significantly related with short-term outcomes in OPCAB patients. However, they suggest that OPCAB patients with low-normal BMI are more susceptible to post-operative blood loss. Body mass index short-term outcomes off-pump coronary artery bypass grafting Figures Figure 1 Figure 2 1 Introduction Obesity, one of the most prevalent public health problems globally, is a direct cause of cardiovascular risk factors ( e.g. , dyslipidemia, type 2 diabetes, hypertension, and sleep disturbances). This century has seen a dramatic increase in incidence of obesity in both developed countries and developing countries, coupled with the average onset age steadily decreasing 1,2 . For example, in China from 1993 to 2015, the prevalence of obesity in children and adolescents increased from 5.0–19.3% 3 . The relationship between obesity and life-expectancy is complex, with the consensus of studies showing increased mortality in people who are either underweight or very obese 4,5 . BMI is calculated by dividing a person's body weight (kg) by the square of their height (m 2 ) and is a commonly used obesity indicator. Studies have shown that obese patients undergoing coronary artery bypass grafting (CABG) are not at higher risk of perioperative death or other adverse outcomes compared to patients with body mass within the normal range 6 . However, multiple studies have shown that underweight patients are at greater risk of death and complications after CABG surgery 7,8 . Obesity does not increase the risk of adverse outcomes in patients with coronary heart disease. Furthermore, elevated BMI has been shown to be a protective factor in the reduction in mortality at 30 days after CABG 9 . The results of a multivariate regression analysis showed that obesity was significantly associated with risk of only superficial sternum wound infection, leg infection and atrial arrhythmias 10 . It is unknown whether BMI is an isolated risk factor for short-outcomes of off-pump coronary artery bypass grafting (OPCAB). The current study is designed to investigate the effects of BMI on in-hospital outcomes of Chinese patients undergoing isolated, primary OPCAB. 2 Methods 2.1 Ethical approval The study was approved by the Ethical Committee of Fuwai Hospital (2019-1301). Given the retrospective nature of the study, patient consent was waived. 2.2 Study design and patient population Patients who received primary and isolated OPCAB at Fuwai Hospital during 2020 were retrospectively included. The inclusion criteria were: (1) age: >18 years old; (2) procedure: primary and isolated OPCAB. The exclusion criteria were: (1) emergency OPCAB; (2) OPCAB performed in conjunction with other surgeries; (3) patients whose outcomes were missing or incomplete; (4) prior cardiac surgery. All included patients were not asked to lose weight during hospitalization. Included patients were divided into three groups according to BMI. Studies have shown that Chinese have lower BMI than Europeans because Chinese have a lower metabolism associated with obesity. 11 Therefore, we used the Working Group on Obesity in China (WGOC) and the Guidelines for the Prevention and Control of Overweight and Obesity in Chinese Adults 12 to define overweight or obesity, as follows: Weight Classification BMI (kg/m 2 ) Obese ≥28 Overweight 24.0-27.9 Normal 18.5-23.9 Underweight <18.5 In this study, few patients were in the underweight and normal weight range, thus we combined these two classifications to create the “low-normal” group (< 24 kg/m 2 ). Hence the final groupings are BMI < 24 kg/m 2 (low-normal weight group), 24 ≤ BMI < 28 kg/m 2 (overweight), and BMI ≥ 28 kg/m 2 (obese). 2.3 Operative techniques All surgical and anesthesia procedures followed standard protocols: 1) patients take antihypertensive and antianginal drugs until the morning of surgery and 2) antiplatelet and anticoagulant drugs are discontinued on admission and replaced with low molecular weight heparin which is continued until the day before surgery. As per standard institutional requirements, all surgeons must be specialized in congenital or valve heart surgery for >3 years before undertaking any CABG procedures. Fuwai Hospital has always been at the forefront of this type of surgery, pioneering the first OPCAB to be performed in China in 1996. The hospital maintains its pre-eminence by requiring surgeons to perform at least 100 CABG procedures before they are considered qualified to perform OPCAB. Once qualified, the choice of OPCAB, as opposed to CABG, for a particular patient is usually at the discretion of the individual surgeon. Standardized anesthesia techniques include sufentanil (1.5 - 2.0 μg/kg), midazolam (0.1 mg/kg), rocuronium bromide (0.6 - 1mg/kg), and sevoflurane (0.5% - 2.5%). In this study, all patients had undergone similar procedures including median thoracotomy; left internal mammary artery tissue samples being routinely collected; collection of large saphenous bundle by standard open methods when required; and a 200 IU/kg dose of heparin administered to obtain an activated clotting time > 300 seconds. Finally, all patients underwent intraoperative cell salvage with autotransfusion of washed, salvaged red blood cells at the end of the operation. 2.4 Data collection Data were collected from hospital electronic medical records and included laboratory test results, perioperative condition, and postoperative recovery. After surgery, the patient was transferred to ICU, where the ICU nurse recorded the duration of mechanical ventilation, chest tube drainage, and other conditions of the patient. 2.5 Outcome events definition The primary outcome was the composite incidence of in-hospital mortality and morbidities. For morbidities, we referenced the definitions for cardiovascular endpoint events formulated by the American Heart Association 13,14 . Non-fatal myocardial infarction is defined as new or presumed new significant ST-segment-T wave (ST-T) changes or new LBBB on the ECG or development of pathological Q waves on the ECG. Low cardiac output is defined as cardiac index (CI) < 2.0 L/min/m 2 ; systolic blood pressure < 90 mmHg; tissue hypoperfusion without hypovolemia; left ventricular assist (LVAD), intra-aortic balloon pump (IABP) and inotropic support after surgeries. Non-fatal stroke is defined as central neurological deficit persisting >72 h. Continuous renal replacement therapy is defined as a patient having acute kidney injury (AKI) or acute renal failure (ARF) after surgery requiring dialysis treatment. Pneumonia is defined as a positive result of bronchial lavage fluid or sputum culture, or changes in chest X-ray. We used chest tube drainage in the first 24 hours after admission to ICU as an indicator of postoperative bleeding. Chest tube drainage was divided by body weight to obtain chest tube drainage/weight. 2.6 Statistical analysis All descriptive data are presented as either mean (standard deviation [SD]) for normally distributed continuous variables, median (interquartile range) for abnormally distributed continuous data, or number (percent) for categorical data, as appropriate. Quantitative data were analyzed using one-way ANOVA if meeting the normal distribution, and Fisher’s least significant difference (LSD) mehtod was applied for post hoc comparisons. The Wilcoxon Rank Sum test was used for quantitative data that did not satisfy the normal distribution. Comparisons of categorical variables were performed using Chi-square tests. All statistical analyses were performed with SPSS version 23.0 software (SPSS Inc., Chicago, IL, USA). A two-sided value of P < 0.05 was considered to indicate statistical significance. 3 Results 3.1 Baseline characteristics The patient selection process is shown in Figure 1. The patients of under-normal weight tended to be older compared with the overweight and obese groups (63.8 ± 8.2 vs. 61.2 ± 9.1, 59.3 ± 9.7, P < 0.001). The underweight group also had the highest proportion of female patients (31.8% vs. 18.3%, 20.1%, P < 0.001) ( Table 1 ). Among the included risk factors, smoking and drinking are more common in overweight and obese patients (42.2% vs. 54.8%, 51.0%; 40.1% vs. 51.2%, 48.6%) However, preoperative myocardial infarction incidence was lower in low-normal weight group. (29.2% vs. 40.2%, 38.6%, P =0.009). 3.2 In-hospital mortality and morbidities There was no difference in adverse events characteristics ( Table 2 ). Significantly, mortality and morbidities were also similar among groups. In addition, cardiac arrest, new pacemaker, atrial fibrillation, non-fatal myocardial infarction, low cardiac output, IABP (Intra-aortic balloon pump), ECMO (Extracorporeal membrane oxygenation), non-fatal stroke, CRRT (Continuous renal replacement therapy), and pneumonia showed similar occurrence across the three cohorts. Overall mortality was 0.001% (1/1006) in the analyzed sample, the only death occurring in the LN group. 3.3 Intraoperative and postoperative characteristics The infused fluid, postoperative bleeding within 24 h and total bleeding in the LN group were markedly higher compared with the OBS group ( Table 3 , P < 0.001). After surgery, hemoglobin levels were lower in the LN group than in the OVW and OBS groups (114.7 ± 57.7 vs. 116.2 ± 17.6, 118.4 ±18.4). Compared with the OVW and OBS group, duration of mechanical ventilation and length of stay in the ICU in the LN group was longer (20.6± 15.5 vs. 17.5 ± 11.4,18.4 ±12.8, P < 0.001) and (70.2 ± 47.0 vs. 66.7 ± 58.9,64 ± 44.0, P < 0.001), respectively. Intraoperative, utilization of cardiovascular medications as well as duration of surgery and anesthesia were not significantly different between the three groups. 4 Discussion It is well established that obesity is one of the most pressing public health problems in the world. Obesity is inextricably linked to hypertension, diabetes, and cardiovascular disease, leading to an increasing number of obese patients undergoing heart surgery. This demographic accounted for 11.9% of patients in our study. Although obesity is a predisposing factor for many chronic diseases, multiple studies 15 , 16 have shown that excessive obesity may improve outcomes for patients with coronary heart disease (known as the "obesity paradox"). In particular, Le-Bert G et al. demonstrated that this paradox was present among elderly obese patients undergoing CABG by median sternotomy 17 . Similar studies 18 have shown that obese patients are i) more likely to be found in younger, male populations and ii) more likely to smoke or drink. However, in our study, coronary heart disease risk factors such as hypertension, diabetes, hyperlipidemia, myocardial infarction were similar in all three groups, which may be caused by the small sample size of the obese group. These findings suggest that obese patients tend to develop coronary artery disease earlier and are more prone to myocardial infarction, as well as surgical revascularization, at a younger age. The current study shows that BMI is not a contributing factor in mortality and/or complications in patients undergoing OPCAB surgery. This is similar to the findings of Castigliano et al. who showed that elevated BMI (≥ 30kg/m 2 ) is not an independent influence on complications and mortality among OPCAB patients 18 . However, a nationwide study with a systematic review and meta-analysis shows a U-shaped association between mortality and body mass index classes, with lower mortality in overweight and obese class I and II patients relative to normal weight patients and increased mortality in underweight and obese class III individuals 19 . Meanwhile, we found that there was no significant difference in the length of stay in the hospital among the three groups following OPCAB. Interestingly, compared with the obese group, the low-normal weight group had more intraoperative fluid infusion and postoperative bleeding and required more blood products, which is consistent with previous reports 20,21 . In addition, the length of stay in the ICU was also significantly prolonged for patients in the low-normal weight group. Recently, it has been demonstrated that adipocytes are able to produce plasminogen activator inhibitor-1 (plasminogen is inactive until converted to plasmin and breaks down fibrin clots), possibly explaining why obese people have less perioperative bleeding 22 . In addition, less hemodilution in obese patients may also contribute to lower risk of postoperative bleeding. However, one study has demonstrated that obesity was not associated with lower risk of bleeding and the procoagulant hemostatic profile in obese individuals may not be sufficient to protect against clinically relevant bleeding 23 , 24 . Nevertheless, BMI is widely accepted as an indicator to predict postoperative blood loss and transfusion. Studies by Ghanta et al. have shown that morbidly obese patients (BMI > 40 kg/m2) have a mortality rate nearly 60% higher than patients falling within the normal weight range and have >2-fold increase in renal failure and >6.5-fold increase in infection of deep sternal wounds 25 . Due to the significant difference in body fat percentage of Chinese patients compared with their European and American counterparts, we have very few morbidly obese patients. Therefore, no adverse events related to excess weight were observed in this study. Previous studies have shown that underweight patients exhibit a higher incidence of postoperative renal insufficiency, longer duration of mechanical ventilation, and longer ICU stay 9,26,27 . Zittermann et al. found that compared with normal and overweight patients, the multivariable-adjusted hazard ratio of 2-year mortality was higher in underweight patients 26 . In our study population, there were only 7 patients classified as underweight, thus they were combined with patients with BMI within normal range, making statistical inference problematic. In our study, the length of stay in the ICU and duration of mechanical ventilation were significantly longer for patients in the low-normal group than in the overweight groups. 5 Limitations Firstly, this is a retrospective study with the limitations inherent in retrospective studies. Secondly, we used a BMI-based definition of obesity in China, which has a lower cut-off value than the Western population, and our results are suitable for Chinese. Thirdly, because this is a single-center study, our sample size is relatively small and may not be sufficient to highlight certain statistical differences. 6 Conclusions The results of this study suggest that obesity is not associated with increased risk of postoperative mortality and complications in Chinese patients undergoing primary and isolated OPCAB. However, lower body weight might be indicative of an increased risk of both incidence and profuseness of intraoperative bleeding for these patients. More extensive studies are warranted to validate the above results. Declarations Author contributions Chen-ying Ding : concept/design, data collection, data analysis/interpretation, drafting article, and approval of article. Wen-hui Qi and Yu-jie An : data collection, data analysis/interpretation, critical revision of article, and approval of article. Yun-tao Yao : Concept/design, critical revision of article, technical and material support. All authors read and approved the final manuscript. Funding statement This work was supported by the Youth Teacher Training Program of Peking Union Medical College (2014zlgc07) and CAMS Innovation Fund for Medical Sciences (CIFMS)-2021-I2M-C&T-B-038. Conflict of interest The authors declare no conflict interest. Data availability The original contributions presented in the study are included in the article, further inquire can be directed to the corresponding author. References Mariapun J, Ng CW, Hairi NN. The Gradual Shift of Overweight, Obesity, and Abdominal Obesity Towards the Poor in a Multi-ethnic Developing Country: Findings From the Malaysian National Health and Morbidity Surveys. J Epidemiol 2018; 28 (6): 279-86. Monteiro CA, Moura EC, Conde WL, Popkin BM. Socioeconomic status and obesity in adult populations of developing countries: a review. Bull World Health Organ 2004; 82 (12): 940-6. Ma S, Hou D, Zhang Y, et al. 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Tables Table 1 Baseline Characteristics Variables Group LN Group OVW Group OBS P P 1 P 2 P 3 Age 63.8(8.2) 61.2(9.1) 59.3(9.7) <0.001* <0.001* <0.001* 0.008* Male 189(68.2) 392(81.7) 199(79.9) <0.001* <0.001* 0.003* 0.618 Risk factors Smoking 117(42.2) 263(54.8) 127(51.0) 0.004* 0.001* 0.054 0.348 Drinking 111(40.1) 246(51.2) 121(48.6) 0.011* 0.002* 0.052 0.532 Chronic obstructive pulmonary disease 4(1.4) 6(1.3) 1(0.4) 0.532 － － － Hypertension 185(66.8) 311(64.8) 180(72.3) 0.121 － － － Diabetes mellitus 110(39.7) 197(41.0) 92(36.9) 0.565 － － － Dyslipidemia 230(83.0) 392(81.7) 215(86.3) 0.284 － － － Atrial fibrillation 11(4.0) 14(2.9) 8(3.2) 0.784 － － － Myocardial infarction 81(29.2) 193(40.2) 96(38.6) 0.009* 0.002* 0.027* 0.09 Percutaneous coronary intervention 23(8.3) 44(9.2) 17(6.8) 0.553 － － － Pulmonary hypertension 3(1.1) 7(1.5) 3(1.2) 0.937 － － － Peripheral vascular diseases 39(14.1) 79(16.5) 36(14.5) 0.628 － － － Neurological events 30(10.8) 37(7.7) 13(5.2) 0.056 － － － LVEF 59.0(7.6) 58.8(6.9) 59.6(7.0) 0.364 － － － Creatinine (mmol/L) 85.0(22.7) 87.6(19.6) 87.3(20.6) 0.239 － － － Values are median (SD) or n (%). LVEF=Left ventricular ejection fraction. P 1, Group LN versus Group OVW; P 2, Group LN versus Group OBS; P 3, Group OVW versus Group OBS; Table 2 Adverse events characteristics Variables Group LN Group OVW Group OBS P Mortality and morbidities 6(2.2) 12(2.5) 8(3.2) 0.735 Mortality 1 (0.4) 0 (0.0) 0(0.0) 0.523 Any morbidity 5(1.8) 12(2.5) 8(3.2) 0.588 Cardiac arrest 1(0.4) 2(0.4) 0(0.0) 0.804 Atrial fibrillation 1(0.4) 4(0.8) 4(1.6) 0.338 New pacemaker 3(1.1) 2(0.4) 2(0.8) 0.486 Non-fatal myocardial infarction 0(0.0) 2(0.4) 1(0.4) 0.616 Low cardiac output 4(1.4) 7(1.5) 3(1.2) 1 Intra-aortic balloon pump 1(0.4) 4(0.8) 0(0.0) 0.525 Extracorporeal membrane oxygenation 4(1.4) 10(2.1) 3(1.2) 0.700 Non-fatal stroke 0(0.0) 2(0.4) 3(1.2) 0.120 Continuous renal replacement therapy 7(2.5) 15(3.1) 6(2.4) 0.803 Pneumonia 151(54.5) 265(55.2) 129(51.8) 0.683 Values are n (%). Table 3 Operative and postoperative characteristics Variables Group LN Group OVW Group OBS P P 1 P 2 P 3 Operative Characteristics Fluid input (ml/kg) 24.5(10.8) 19.9(9.2) 21.6(7.1) <0.001* <0.001* <0.001* 0.027* Epinephrine 29(10.5) 55(11.5) 24(9.6) 0.741 － － － Dopamine 144(52.0) 240(50.0) 141(56.6) 0.238 － － － Milrinone 24(8.7) 32(6.7) 17(6.8) 0.580 － － － Norepinephrine 54(19.5) 86(17.9) 44(17.7) 0.839 － － － Nitroglycerin 178(64.3) 318(66.3) 168(67.5) 0.735 － － － Surgery duration, min 208.6(47.0) 206.9(46.7) 213.5(45.1) 0.188 － － － Anesthesia duration, min 259.3(51.8) 255.1(48.8) 263.7(50.1) 0.083 － － － Postoperative Characteristics Bleeding within 24 h (ml/kg) 9.0(5.2) 8.0(6.1) 6.9(4.8) <0.001* 0.022* <0.001* 0.011* Total bleeding (ml/kg) 17.9(11.7) 14.9(9.9) 12.1(8.2) <0.001* <0.001* <0.001* 0.001* Chest drainage duration, d 4.7(2.2) 4.7(2.4) 4.6(1.8) 0.767 － － － Reoperation for bleeding 3(1.1) 6(1.3) 2(0.8) 0.927 － － － Postoperative hemoglobin (g/L) 114.7(57.7) 116.2(17.6) 118.4(18.4) <0.001* 0.001* <0.001* 0.353 Postoperative platelet count (10 9 /L) 187.7(63.8) 187.3(55.6) 192.9(61.7) 0.451 － － － Red blood cell transfusion rate 9(3.2) 5(1.0) 5(2.0) 0.095 － － － Fresh frozen plasma transfusion rate 10(3.6) 9(1.9) 6(2.4) 0.341 － － － Platelet concentrates transfusion rate 0 0 0 NA － － － Any transfusion rate 16(5.8) 14(2.9) 9(3.6) 0.145 － － － Mechanical ventilation duration (h) 20.6(15.5) 17.5(11.4) 18.4(12.8) 0.006* 0.001* 0.001* 1 Length of stay in ICU (h) 70.2(47.0) 66.7(58.9) 64.5(44.2) <0.001* 0.001* 0.001* 0.056 Readmission to ICU 5.0(1.8) 4(0.8) 3(1.2) 0.891 － － － Length of stay in the hospital, d 8.3(2.9) 8.5(5.4) 8.54(4.3) 0.832 － － － Values are median (SD) or n (%). P1, Group LN versus Group OVW; P2, Group LN versus Group OBS; P3, Group OVW versus Group OBS. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 11 Feb, 2024 Read the published version in Journal of Cardiothoracic Surgery → Version 1 posted Editorial decision: Revision requested 05 Nov, 2023 Reviews received at journal 02 Oct, 2023 Reviewers agreed at journal 25 Sep, 2023 Reviewers agreed at journal 25 Sep, 2023 Reviewers invited by journal 25 Sep, 2023 Editor assigned by journal 24 Sep, 2023 Submission checks completed at journal 07 Aug, 2023 First submitted to journal 07 Aug, 2023 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. 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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-3240589","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":224786716,"identity":"8f7528fa-6a05-48ab-9fcf-ae8aac4dc160","order_by":0,"name":"Chen ying Ding","email":"","orcid":"","institution":"Hohhot First Hospital","correspondingAuthor":false,"prefix":"","firstName":"Chen","middleName":"ying","lastName":"Ding","suffix":""},{"id":224786717,"identity":"83be7410-a5b9-413d-8958-0d0fd646a365","order_by":1,"name":"Wen hui Qi","email":"","orcid":"","institution":"Harrison International Peace Hospital","correspondingAuthor":false,"prefix":"","firstName":"Wen","middleName":"hui","lastName":"Qi","suffix":""},{"id":224786718,"identity":"dffa01a6-e38c-499d-a4b2-4f54867cef8e","order_by":2,"name":"Yujie An","email":"","orcid":"","institution":"the Friendship Hospital of Ili Kazakh Autonomous Prefecture, Xinjiang Uygur Autonomous Region","correspondingAuthor":false,"prefix":"","firstName":"Yujie","middleName":"","lastName":"An","suffix":""},{"id":224786719,"identity":"984752dc-b119-4b8e-bb52-44e6b92aa46d","order_by":3,"name":"Yun-tai Yao","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAyUlEQVRIiWNgGAWjYNACAyBmb2x88IFI9YwNYC08h5sNZxCvBQQk0tukOYhy0o3c4w9+FByW55d82CDNwGAnp9tAUEteYmOPwWHDmbMTG4wLGJKNzQ4Q1JJj2MBjcJhxw+3EhuQZDAcStxGjpfGPwWH7DTcPNhzmIVZLM9CWxA03GBubidIieeaN4WwZg/TkmT2JzYwzDIjwC9/xHIOPb/5Y2/azH3/+40OFnRxBLQoQBc0wdxJQDgLyDWCqjgilo2AUjIJRMGIBAA+mSbZYtX2SAAAAAElFTkSuQmCC","orcid":"","institution":"Chinese Academy of Medical Sciences","correspondingAuthor":true,"prefix":"","firstName":"Yun-tai","middleName":"","lastName":"Yao","suffix":""}],"badges":[],"createdAt":"2023-08-07 04:29:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3240589/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3240589/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s13019-024-02586-1","type":"published","date":"2024-02-11T15:00:44+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":41443558,"identity":"2ecd8487-9d50-4e7a-889d-5b6a04a910bb","added_by":"auto","created_at":"2023-08-11 14:19:20","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":26407,"visible":true,"origin":"","legend":"\u003cp\u003eEnrollment flowchart\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-3240589/v1/5f24740e8ba0ebc7bd0223fe.png"},{"id":41443559,"identity":"9363c22c-817b-4cbb-b9ae-5306ce3a96aa","added_by":"auto","created_at":"2023-08-11 14:19:20","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":49844,"visible":true,"origin":"","legend":"\u003cp\u003eBMI distribution across the analyzed sample shows an approximately normal distribution as seen by the curve.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-3240589/v1/2c308be033394f15d0cd9b29.png"},{"id":51005484,"identity":"b9ada16b-e26b-45ca-a13d-179c78fe126a","added_by":"auto","created_at":"2024-02-12 15:08:36","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":419084,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3240589/v1/f985a194-9832-4350-a629-b252fa0e0571.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"The Effect of Body Mass Index on Short-term Outcomes in Patients Undergoing Off-pump Coronary Artery Bypass Grafting Surgery: A Retrospective Study from a Single Cardiovascular Center","fulltext":[{"header":"1 Introduction","content":"\u003cp\u003eObesity, one of the most prevalent public health problems globally, is a direct cause of cardiovascular risk factors (\u003cem\u003ee.g.\u003c/em\u003e, dyslipidemia, type 2 diabetes, hypertension, and sleep disturbances). This century has seen a dramatic increase in incidence of obesity in both developed countries and developing countries, coupled with the average onset age steadily decreasing\u003csup\u003e1,2\u003c/sup\u003e. For example, in China from 1993 to 2015, the prevalence of obesity in children and adolescents increased from 5.0\u0026ndash;19.3%\u003csup\u003e3\u003c/sup\u003e. The relationship between obesity and life-expectancy is complex, with the consensus of studies showing increased mortality in people who are either underweight or very obese\u003csup\u003e4,5\u003c/sup\u003e. BMI is calculated by dividing a person's body weight (kg) by the square of their height (m\u003csup\u003e2\u003c/sup\u003e) and is a commonly used obesity indicator. Studies have shown that obese patients undergoing coronary artery bypass grafting (CABG) are not at higher risk of perioperative death or other adverse outcomes compared to patients with body mass within the normal range\u003csup\u003e6\u003c/sup\u003e. However, multiple studies have shown that underweight patients are at greater risk of death and complications after CABG surgery\u003csup\u003e7,8\u003c/sup\u003e. Obesity does not increase the risk of adverse outcomes in patients with coronary heart disease. Furthermore, elevated BMI has been shown to be a protective factor in the reduction in mortality at 30 days after CABG\u003csup\u003e9\u003c/sup\u003e. The results of a multivariate regression analysis showed that obesity was significantly associated with risk of only superficial sternum wound infection, leg infection and atrial arrhythmias\u003csup\u003e10\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eIt is unknown whether BMI is an isolated risk factor for short-outcomes of off-pump coronary artery bypass grafting (OPCAB). The current study is designed to investigate the effects of BMI on in-hospital outcomes of Chinese patients undergoing isolated, primary OPCAB.\u003c/p\u003e"},{"header":"2 Methods","content":"\u003cp\u003e\u003cstrong\u003e2.1 Ethical approval\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study was approved by the Ethical Committee of Fuwai Hospital (2019-1301). Given the retrospective nature of the study, patient consent was waived.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2 Study design and patient population\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePatients who received primary and isolated OPCAB at Fuwai Hospital during 2020 were retrospectively included.\u003c/p\u003e\n\u003cp\u003eThe inclusion criteria were: (1) age: \u0026gt;18 years old; (2) procedure: primary and isolated OPCAB. The exclusion criteria were: (1) emergency OPCAB; (2) OPCAB performed in conjunction with other surgeries; (3) patients whose outcomes were missing or incomplete; (4) prior cardiac surgery. All included patients were not asked to lose weight during hospitalization.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIncluded patients were divided into three groups according to BMI. Studies have shown that Chinese have lower BMI than Europeans because Chinese have a lower metabolism associated with obesity.\u003csup\u003e11\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003eTherefore, we used the Working Group on Obesity in China (WGOC) and the Guidelines for the Prevention and Control of Overweight and Obesity in Chinese Adults\u003csup\u003e12\u003c/sup\u003e to define overweight or obesity, as follows:\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"49.376114081996434%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeight Classification\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"50.623885918003566%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eBMI (kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"49.376114081996434%\" valign=\"top\"\u003e\n \u003cp\u003eObese\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"50.623885918003566%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026ge;28\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"49.376114081996434%\" valign=\"top\"\u003e\n \u003cp\u003eOverweight\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"50.623885918003566%\" valign=\"top\"\u003e\n \u003cp\u003e24.0-27.9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"49.376114081996434%\" valign=\"top\"\u003e\n \u003cp\u003eNormal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"50.623885918003566%\" valign=\"top\"\u003e\n \u003cp\u003e18.5-23.9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"49.376114081996434%\" valign=\"top\"\u003e\n \u003cp\u003eUnderweight\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"50.623885918003566%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;18.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn this study, few patients were in the underweight and normal weight range, thus we combined these two classifications to create the \u0026ldquo;low-normal\u0026rdquo; group (\u0026lt; 24 kg/m\u003csup\u003e2\u003c/sup\u003e). Hence the final groupings are BMI \u0026lt; 24 kg/m\u003csup\u003e2\u003c/sup\u003e (low-normal weight group), 24 \u0026le; BMI \u0026lt; 28 kg/m\u003csup\u003e2\u003c/sup\u003e (overweight), and BMI \u0026ge; 28 kg/m\u003csup\u003e2\u003c/sup\u003e (obese).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.3 Operative techniques\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll surgical and anesthesia procedures followed standard protocols: 1) patients take antihypertensive and antianginal drugs until the morning of surgery and 2) antiplatelet and anticoagulant drugs are discontinued on admission and replaced with low molecular weight heparin which is continued until the day before surgery. As per standard institutional requirements, all surgeons must be specialized in congenital or valve heart surgery for \u0026gt;3 years before undertaking any CABG procedures. Fuwai Hospital has always been at the forefront of this type of surgery, pioneering the first OPCAB to be performed in China in 1996. The hospital maintains its pre-eminence by requiring surgeons to perform at least 100 CABG procedures before they are considered qualified to perform OPCAB. Once qualified, the choice of OPCAB, as opposed to CABG, for a particular patient is usually at the discretion of the individual surgeon.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eStandardized anesthesia techniques include sufentanil (1.5 - 2.0 \u0026mu;g/kg), midazolam (0.1 mg/kg), rocuronium bromide (0.6 - 1mg/kg), and sevoflurane (0.5% - 2.5%). In this study, all patients had undergone similar procedures including median thoracotomy; left internal mammary artery\u0026nbsp;tissue samples\u0026nbsp;being routinely collected; collection of large saphenous bundle by standard open methods when required; and a 200 IU/kg dose of heparin administered to obtain an activated clotting time \u0026gt; 300 seconds. Finally, all patients underwent intraoperative cell salvage with autotransfusion of washed, salvaged red blood cells at the end of the operation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.4 Data collection\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData were collected from hospital electronic medical records and included laboratory test results, perioperative condition, and postoperative recovery. After surgery, the patient was transferred to ICU, where the ICU nurse recorded the duration of mechanical ventilation, chest tube drainage, and other conditions of the patient.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.5 Outcome events definition\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe primary outcome was the composite incidence of in-hospital mortality and morbidities. For morbidities, we referenced the definitions for cardiovascular endpoint events formulated by the American Heart Association\u0026nbsp;\u003csup\u003e13,14\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eNon-fatal myocardial infarction\u003c/em\u003e is defined as new or presumed new significant ST-segment-T wave (ST-T) changes or new LBBB on the ECG or development of pathological Q waves on the ECG.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eLow cardiac output\u003c/em\u003e is defined as cardiac index (CI) \u0026lt; 2.0\u0026nbsp;L/min/m\u003csup\u003e2\u003c/sup\u003e; systolic blood pressure \u0026lt; 90 mmHg; tissue hypoperfusion without hypovolemia; left ventricular assist (LVAD), intra-aortic balloon pump (IABP) and inotropic support after surgeries.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eNon-fatal stroke\u003c/em\u003e is defined as\u0026nbsp;central neurological deficit persisting \u0026gt;72 h.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eContinuous renal replacement therapy\u0026nbsp;\u003c/em\u003eis defined as a patient having acute kidney injury (AKI) or acute renal failure (ARF) after surgery requiring dialysis treatment.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ePneumonia\u003c/em\u003e is defined as a positive result of bronchial lavage fluid or sputum culture, or\u0026nbsp;changes in chest X-ray.\u003c/p\u003e\n\u003cp\u003eWe used chest tube drainage in the first 24 hours after admission to ICU as an indicator of postoperative bleeding. Chest tube drainage was divided by body weight to obtain chest tube drainage/weight.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.6 Statistical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll descriptive data are presented as either mean (standard deviation [SD]) for normally distributed continuous variables, median (interquartile range) for abnormally distributed continuous data, or number (percent) for categorical data, as appropriate. Quantitative data were analyzed using one-way ANOVA if meeting the normal distribution, and Fisher\u0026rsquo;s least significant difference (LSD) mehtod was applied for post hoc comparisons. The Wilcoxon Rank Sum test was used for quantitative data that did not satisfy the normal distribution.\u0026nbsp;Comparisons of categorical variables were performed using Chi-square tests.\u003c/p\u003e\n\u003cp\u003eAll statistical analyses were performed with SPSS version 23.0 software (SPSS Inc., Chicago, IL, USA). A two-sided value of \u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u0026lt; 0.05 was considered to indicate statistical significance.\u0026nbsp;\u003c/p\u003e"},{"header":"3 Results","content":"\u003cp\u003e\u003cstrong\u003e3.1 Baseline characteristics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe patient selection process is shown in \u003cstrong\u003eFigure 1.\u0026nbsp;\u003c/strong\u003eThe patients of under-normal weight tended to be older compared with the overweight and obese groups (63.8 \u0026plusmn; 8.2 vs. 61.2 \u0026plusmn; 9.1, 59.3 \u0026plusmn; 9.7, \u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u0026lt; 0.001). The underweight group also had the highest proportion\u0026nbsp;of female patients (31.8%\u0026nbsp;\u003cem\u003evs.\u003c/em\u003e 18.3%, 20.1%, \u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u0026lt; 0.001)\u0026nbsp;(\u003cstrong\u003eTable 1\u003c/strong\u003e). Among the included risk factors, smoking and drinking are more common in overweight and obese patients (42.2% vs. 54.8%, 51.0%; 40.1% vs. 51.2%, 48.6%)\u0026nbsp;However, preoperative myocardial infarction incidence was lower in low-normal weight group. (29.2% \u003cem\u003evs.\u003c/em\u003e 40.2%, 38.6%,\u003cem\u003e\u0026nbsp;P\u003c/em\u003e=0.009).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.2 In-hospital mortality and morbidities\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;There was no difference in adverse events characteristics (\u003cstrong\u003eTable 2\u003c/strong\u003e). Significantly, mortality and morbidities were also similar among groups. In addition, cardiac arrest, new pacemaker, atrial fibrillation, non-fatal myocardial infarction, low cardiac output, IABP (Intra-aortic balloon pump), ECMO (Extracorporeal membrane oxygenation), non-fatal stroke, CRRT (Continuous renal replacement therapy), and pneumonia showed similar occurrence across the three cohorts. Overall mortality was 0.001% (1/1006) in the analyzed sample, the only death occurring\u0026nbsp;in the LN group.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.3 Intraoperative\u0026nbsp;and postoperative characteristics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe infused fluid, postoperative bleeding within 24 h and total bleeding in the LN group were markedly higher compared with the OBS group (\u003cstrong\u003eTable 3\u003c/strong\u003e, \u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u0026lt; 0.001). After surgery, hemoglobin levels were lower in the LN group than in the OVW and OBS groups (114.7 \u0026plusmn; 57.7 vs. 116.2 \u0026plusmn; 17.6, 118.4 \u0026plusmn;18.4). Compared with the OVW and OBS group, duration of mechanical ventilation and length of stay in the ICU in the LN group was longer (20.6\u0026plusmn; 15.5 vs. 17.5 \u0026plusmn; 11.4,18.4 \u0026plusmn;12.8, \u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u0026lt; 0.001) and (70.2 \u0026plusmn; 47.0 vs. 66.7 \u0026plusmn; 58.9,64 \u0026plusmn; 44.0, \u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u0026lt; 0.001), respectively. Intraoperative, utilization of cardiovascular medications as well as duration of surgery and anesthesia were not significantly different between the three groups.\u003c/p\u003e"},{"header":"4 Discussion","content":"\u003cp\u003eIt is well established that obesity is one of the most pressing public health problems in the world. Obesity is inextricably linked to hypertension, diabetes, and cardiovascular disease, leading to an increasing number of obese patients undergoing heart surgery. This demographic accounted for 11.9% of patients in our study. Although obesity is a predisposing factor for many chronic diseases, multiple studies\u003csup\u003e15\u003c/sup\u003e\u003csup\u003e,\u003c/sup\u003e\u003csup\u003e16\u003c/sup\u003e have shown that excessive obesity may improve outcomes for patients with coronary heart disease (known as the \u0026quot;obesity paradox\u0026quot;). In particular, Le-Bert G \u003cem\u003eet al.\u003c/em\u003e demonstrated that this paradox was present among elderly obese patients undergoing CABG by median sternotomy\u003csup\u003e17\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eSimilar studies\u003csup\u003e18\u003c/sup\u003e have shown that obese patients are i) more likely to be found in younger, male populations and ii) more likely to smoke or drink. However, in our study, coronary heart disease risk factors such as hypertension, diabetes, hyperlipidemia, myocardial infarction were similar in all three groups, which may be caused by the small sample size of the\u0026nbsp;obese group. These findings suggest that obese patients tend to develop coronary artery disease earlier and are more prone to myocardial infarction, as well as surgical revascularization, at a younger age.\u003c/p\u003e\n\u003cp\u003eThe current study shows that BMI is not a contributing factor in mortality and/or complications in patients undergoing OPCAB surgery. This is similar to the findings of Castigliano \u003cem\u003eet al.\u003c/em\u003e who showed that elevated BMI (\u0026ge; 30kg/m\u003csup\u003e2\u003c/sup\u003e) is not an independent influence on complications and mortality among OPCAB patients\u003csup\u003e18\u003c/sup\u003e. However, a nationwide study with a systematic review and meta-analysis shows a U-shaped association between mortality and body mass index classes, with lower mortality in overweight and obese class I and II patients relative to normal weight patients and increased mortality in underweight and obese class III \u0026nbsp; individuals\u003csup\u003e19\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eMeanwhile, we found that there was no significant difference in the length of stay in the hospital among the three groups following OPCAB. Interestingly, compared with the obese group, the low-normal weight group had more intraoperative fluid infusion and postoperative bleeding and required more blood products, which is consistent with previous reports\u003csup\u003e20,21\u003c/sup\u003e. In addition, the length of stay in the ICU was also significantly prolonged for patients in the low-normal weight group.\u0026nbsp;Recently, it has been demonstrated that adipocytes are able to produce plasminogen activator inhibitor-1 (plasminogen is inactive until converted to plasmin and breaks down fibrin clots), possibly explaining why obese people have less perioperative bleeding\u003csup\u003e22\u003c/sup\u003e. In addition, less hemodilution in obese patients may also contribute to lower risk of postoperative bleeding. However, one study has demonstrated that obesity was not associated with lower risk of bleeding and the procoagulant hemostatic profile in obese individuals may not be sufficient to protect against clinically relevant bleeding\u003csup\u003e23\u003c/sup\u003e\u003csup\u003e,\u003c/sup\u003e\u003csup\u003e24\u003c/sup\u003e. Nevertheless, BMI is widely accepted as an indicator to predict postoperative blood loss and transfusion.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;Studies by Ghanta \u003cem\u003eet al.\u003c/em\u003e have shown that morbidly obese patients (BMI \u0026gt;\u003cins cite=\"mailto:editor\"\u003e\u0026nbsp;\u003c/ins\u003e40 kg/m2) have a mortality rate nearly 60% higher than patients falling within the normal weight range and have \u0026gt;2-fold increase in renal failure and \u0026gt;6.5-fold increase in infection of deep sternal wounds\u003csup\u003e25\u003c/sup\u003e. Due to the significant difference in body fat percentage of Chinese patients compared with their European and American counterparts, we have very few morbidly obese patients. Therefore, no adverse events related to excess weight were observed in this study.\u003c/p\u003e\n\u003cp\u003ePrevious studies have shown that underweight patients exhibit a higher incidence of postoperative renal insufficiency, longer duration of mechanical ventilation, and longer ICU stay\u003csup\u003e9,26,27\u003c/sup\u003e. Zittermann \u003cem\u003eet al.\u003c/em\u003e found that compared with normal and overweight patients, the multivariable-adjusted hazard ratio of 2-year mortality was higher in underweight patients\u003csup\u003e26\u003c/sup\u003e. In our study population, there were only 7 patients classified as underweight, thus they were combined with patients with BMI within normal range, making statistical inference problematic. In our study, the length of stay in the ICU and duration of mechanical ventilation were significantly longer for patients in the low-normal group than in the overweight groups.\u003c/p\u003e"},{"header":"5 Limitations","content":"\u003cp\u003eFirstly, this is a retrospective study with the limitations inherent in retrospective studies. Secondly, we used a BMI-based definition of obesity in China, which has a lower cut-off value than the Western population, and our results are suitable for Chinese. Thirdly, because this is a single-center study, our sample size is relatively small and may not be sufficient to highlight certain statistical differences.\u003c/p\u003e"},{"header":"6 Conclusions","content":"\u003cp\u003eThe results of this study suggest that obesity is not associated with increased risk of postoperative mortality and complications in Chinese patients undergoing primary and isolated OPCAB. However, lower body weight might be indicative of an increased risk of both incidence and profuseness of intraoperative bleeding for these patients. More extensive studies are warranted to validate the above results.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eChen-ying Ding\u003c/strong\u003e: concept/design, data collection, data analysis/interpretation, drafting article, and approval of article. \u003cstrong\u003eWen-hui Qi and Yu-jie An\u003c/strong\u003e: data collection, data analysis/interpretation, critical revision of article, and approval of article. \u003cstrong\u003eYun-tao Yao\u003c/strong\u003e: Concept/design, critical revision of article, technical and material support. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by the Youth Teacher Training Program of Peking Union Medical College (2014zlgc07) and CAMS Innovation Fund for Medical Sciences (CIFMS)-2021-I2M-C\u0026amp;T-B-038.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no conflict interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe original contributions presented in the study are included in the article, further inquire can be directed to the corresponding author.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eMariapun J, Ng CW, Hairi NN. 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The impact of body mass index on short- and long-term outcomes in patients undergoing coronary artery graft bypass. \u003cem\u003ePLoS One\u003c/em\u003e 2014; \u003cstrong\u003e9\u003c/strong\u003e(4): e95223.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"877\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"76.91415313225058%\" colspan=\"5\"\u003e\n \u003cp\u003e\u003cstrong\u003eTable 1\u0026nbsp;\u003c/strong\u003eBaseline Characteristics\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.77262180974478%\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.77262180974478%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.540603248259861%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003eVariables\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003eGroup LN\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003eGroup OVW\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003eGroup OBS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003eAge\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e63.8(8.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e61.2(9.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e59.3(9.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e0.008*\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e189(68.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e392(81.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e199(79.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.003*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e0.618\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003eRisk factors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Smoking\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e117(42.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e263(54.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e127(51.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.004*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.054\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e0.348\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Drinking\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e111(40.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e246(51.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e121(48.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.011*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.002*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.052\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e0.532\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Chronic obstructive pulmonary disease\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e4(1.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e6(1.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e1(0.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.532\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Hypertension\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e185(66.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e311(64.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e180(72.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.121\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Diabetes mellitus\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e110(39.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e197(41.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e92(36.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.565\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Dyslipidemia\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e230(83.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e392(81.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e215(86.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.284\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Atrial fibrillation\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e11(4.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e14(2.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e8(3.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.784\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Myocardial infarction\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e81(29.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e193(40.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e96(38.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.009*\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.002*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.027*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e0.09\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Percutaneous coronary intervention\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e23(8.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e44(9.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e17(6.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.553\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Pulmonary hypertension\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e3(1.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e7(1.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e3(1.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.937\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Peripheral vascular diseases\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e39(14.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e79(16.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e36(14.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.628\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Neurological events\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e30(10.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e37(7.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e13(5.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.056\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; LVEF\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e59.0(7.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e58.8(6.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e59.6(7.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.364\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"37.16608594657375%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Creatinine (mmol/L)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.40766550522648%\"\u003e\n \u003cp\u003e85.0(22.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.73054587688734%\"\u003e\n \u003cp\u003e87.6(19.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.801393728222996%\"\u003e\n \u003cp\u003e87.3(20.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e0.239\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.781649245063879%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"7.549361207897793%\"\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"100%\" colspan=\"8\" valign=\"top\"\u003e\n \u003cp\u003eValues are median (SD) or n (%). LVEF=Left ventricular ejection fraction. \u003cem\u003eP\u003c/em\u003e1, Group LN versus Group OVW; \u003cem\u003eP\u003c/em\u003e2, Group LN versus Group OBS; \u003cem\u003eP\u003c/em\u003e3, Group OVW versus Group OBS;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"666\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"100%\" colspan=\"5\"\u003e\n \u003cp\u003e\u003cstrong\u003eTable 2\u0026nbsp;\u003c/strong\u003eAdverse events characteristics\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.8018018018018%\"\u003e\n \u003cp\u003eVariables\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.162162162162161%\"\u003e\n \u003cp\u003eGroup LN\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.315315315315315%\"\u003e\n \u003cp\u003eGroup OVW\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.963963963963964%\"\u003e\n \u003cp\u003eGroup OBS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.756756756756757%\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.8018018018018%\"\u003e\n \u003cp\u003eMortality and morbidities\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.162162162162161%\"\u003e\n \u003cp\u003e6(2.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.315315315315315%\"\u003e\n \u003cp\u003e12(2.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.963963963963964%\"\u003e\n \u003cp\u003e8(3.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.756756756756757%\"\u003e\n \u003cp\u003e0.735\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.8018018018018%\"\u003e\n \u003cp\u003eMortality\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.162162162162161%\"\u003e\n \u003cp\u003e1 (0.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.315315315315315%\"\u003e\n \u003cp\u003e0 (0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.963963963963964%\"\u003e\n \u003cp\u003e0(0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.756756756756757%\"\u003e\n \u003cp\u003e0.523\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.8018018018018%\"\u003e\n \u003cp\u003eAny morbidity\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.162162162162161%\"\u003e\n \u003cp\u003e5(1.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.315315315315315%\"\u003e\n \u003cp\u003e12(2.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.963963963963964%\"\u003e\n \u003cp\u003e8(3.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.756756756756757%\"\u003e\n \u003cp\u003e0.588\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.8018018018018%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; \u0026nbsp;Cardiac arrest\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.162162162162161%\"\u003e\n \u003cp\u003e1(0.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.315315315315315%\"\u003e\n \u003cp\u003e2(0.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.963963963963964%\"\u003e\n \u003cp\u003e0(0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.756756756756757%\"\u003e\n \u003cp\u003e0.804\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.8018018018018%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; \u0026nbsp;Atrial fibrillation\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.162162162162161%\"\u003e\n \u003cp\u003e1(0.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.315315315315315%\"\u003e\n \u003cp\u003e4(0.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.963963963963964%\"\u003e\n \u003cp\u003e4(1.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.756756756756757%\"\u003e\n \u003cp\u003e0.338\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.8018018018018%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; \u0026nbsp;New pacemaker\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.162162162162161%\"\u003e\n \u003cp\u003e3(1.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.315315315315315%\"\u003e\n \u003cp\u003e2(0.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.963963963963964%\"\u003e\n \u003cp\u003e2(0.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.756756756756757%\"\u003e\n \u003cp\u003e0.486\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.8018018018018%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; \u0026nbsp;Non-fatal myocardial infarction\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.162162162162161%\"\u003e\n \u003cp\u003e0(0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.315315315315315%\"\u003e\n \u003cp\u003e2(0.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.963963963963964%\"\u003e\n \u003cp\u003e1(0.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.756756756756757%\"\u003e\n \u003cp\u003e0.616\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.8018018018018%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; \u0026nbsp;Low cardiac output\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.162162162162161%\"\u003e\n \u003cp\u003e4(1.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.315315315315315%\"\u003e\n \u003cp\u003e7(1.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.963963963963964%\"\u003e\n \u003cp\u003e3(1.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.756756756756757%\"\u003e\n \u003cp\u003e1\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.8018018018018%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; \u0026nbsp;Intra-aortic balloon pump\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.162162162162161%\"\u003e\n \u003cp\u003e1(0.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.315315315315315%\"\u003e\n \u003cp\u003e4(0.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.963963963963964%\"\u003e\n \u003cp\u003e0(0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.756756756756757%\"\u003e\n \u003cp\u003e0.525\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.8018018018018%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; \u0026nbsp;Extracorporeal membrane oxygenation\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.162162162162161%\"\u003e\n \u003cp\u003e4(1.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.315315315315315%\"\u003e\n \u003cp\u003e10(2.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.963963963963964%\"\u003e\n \u003cp\u003e3(1.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.756756756756757%\"\u003e\n \u003cp\u003e0.700\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.8018018018018%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; \u0026nbsp;Non-fatal stroke\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.162162162162161%\"\u003e\n \u003cp\u003e0(0.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.315315315315315%\"\u003e\n \u003cp\u003e2(0.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.963963963963964%\"\u003e\n \u003cp\u003e3(1.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.756756756756757%\"\u003e\n \u003cp\u003e0.120\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.8018018018018%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; \u0026nbsp;Continuous renal replacement therapy\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.162162162162161%\"\u003e\n \u003cp\u003e7(2.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.315315315315315%\"\u003e\n \u003cp\u003e15(3.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.963963963963964%\"\u003e\n \u003cp\u003e6(2.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.756756756756757%\"\u003e\n \u003cp\u003e0.803\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"51.8018018018018%\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; \u0026nbsp;Pneumonia\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.162162162162161%\"\u003e\n \u003cp\u003e151(54.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"15.315315315315315%\"\u003e\n \u003cp\u003e265(55.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.963963963963964%\"\u003e\n \u003cp\u003e129(51.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"6.756756756756757%\"\u003e\n \u003cp\u003e0.683\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"100%\" colspan=\"5\"\u003e\n \u003cp\u003eValues are n (%).\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"860\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"5\"\u003e\n \u003cp\u003e\u003cstrong\u003eTable 3\u0026nbsp;\u003c/strong\u003eOperative and postoperative characteristics\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eVariables\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eGroup LN\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eGroup OVW\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eGroup OBS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eOperative Characteristics\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Fluid input (ml/kg)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e24.5(10.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e19.9(9.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e21.6(7.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.027*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Epinephrine\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e29(10.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e55(11.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e24(9.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.741\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Dopamine\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e144(52.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e240(50.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e141(56.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.238\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Milrinone\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e24(8.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e32(6.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e17(6.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.580\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Norepinephrine\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e54(19.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e86(17.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e44(17.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.839\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Nitroglycerin\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e178(64.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e318(66.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e168(67.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.735\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Surgery duration, min\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e208.6(47.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e206.9(46.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e213.5(45.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.188\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Anesthesia duration, min\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e259.3(51.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e255.1(48.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e263.7(50.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.083\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePostoperative Characteristics\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Bleeding within 24 h (ml/kg)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e9.0(5.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e8.0(6.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e6.9(4.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.022*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.011*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Total bleeding (ml/kg)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e17.9(11.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e14.9(9.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e12.1(8.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Chest drainage duration, d\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.7(2.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.7(2.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.6(1.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.767\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Reoperation for bleeding\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3(1.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e6(1.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2(0.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.927\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Postoperative hemoglobin (g/L)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e114.7(57.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e116.2(17.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e118.4(18.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.353\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Postoperative platelet count (10\u003csup\u003e9\u003c/sup\u003e/L)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e187.7(63.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e187.3(55.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e192.9(61.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.451\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Red blood cell transfusion rate\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e9(3.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5(1.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5(2.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.095\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Fresh frozen plasma transfusion rate\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e10(3.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e9(1.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e6(2.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.341\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Platelet concentrates transfusion rate\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Any transfusion rate\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e16(5.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e14(2.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e9(3.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.145\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Mechanical ventilation duration (h)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e20.6(15.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e17.5(11.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e18.4(12.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.006*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Length of stay in ICU (h)\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e70.2(47.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e66.7(58.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e64.5(44.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.001*\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.056\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Readmission to ICU\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5.0(1.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4(0.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3(1.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.891\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cem\u003e\u0026nbsp; Length of stay in the hospital, d\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e8.3(2.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e8.5(5.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e8.54(4.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.832\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e－\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eValues are median (SD) or n (%). P1, Group LN versus Group OVW; P2, Group LN versus Group OBS; P3, Group OVW versus Group OBS.\u0026nbsp;\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-cardiothoracic-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jcts","sideBox":"Learn more about [Journal of Cardiothoracic Surgery](http://cardiothoracicsurgery.biomedcentral.com)","snPcode":"13019","submissionUrl":"https://submission.nature.com/new-submission/13019/3","title":"Journal of Cardiothoracic Surgery","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Body mass index, short-term outcomes, off-pump, coronary artery bypass grafting","lastPublishedDoi":"10.21203/rs.3.rs-3240589/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3240589/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eObjective\u003c/h2\u003e \u003cp\u003eThis study is designed to investigate the impact of body mass index (BMI) on the short-term outcomes of patients undergoing off-pump coronary artery bypass graft (OPCAB) surgery.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eData was obtained from 1006 Chinese patients who underwent isolated, primary OPCAB at a high-traffic cardiovascular center during 2020. Subjects were categorized, by BMI, into a low-normal weight (LN) group (BMI\u0026thinsp;\u0026lt;\u0026thinsp;24 kg/m\u003csup\u003e2\u003c/sup\u003e), an overweight (OVW) group (24\u0026thinsp;\u0026le;\u0026thinsp;BMI\u0026thinsp;\u0026lt;\u0026thinsp;28 kg/m\u003csup\u003e2\u003c/sup\u003e), and an obese (OBS) group (BMI\u0026thinsp;\u0026ge;\u0026thinsp;28 kg/m\u003csup\u003e2\u003c/sup\u003e). Information pertaining to patients\u0026rsquo; short-term outcomes (including incidence of mortality and morbidities; duration of postoperative mechanical ventilation; length of stay in the ICU and hospital; postoperative bleeding; \u003cem\u003eetc\u003c/em\u003e.) were extracted, and the data from each group were compared.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe incidences of in-hospital mortality and morbidities were similar for all three groups. The volume of fluid infusion, postoperative bleeding within 24 h and total bleeding in LN group were higher than those in the OBS group (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). The hemoglobin level was lower in the LN group than that in the OBS group (\u003cem\u003eP\u0026thinsp;\u0026lt;\u003c/em\u003e\u0026thinsp;0.001). Duration of mechanical ventilation and length of stay in the ICU in the LN group were longer than those in the OBS group (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eOur results demonstrate that BMI is not significantly related with short-term outcomes in OPCAB patients. However, they suggest that OPCAB patients with low-normal BMI are more susceptible to post-operative blood loss.\u003c/p\u003e","manuscriptTitle":"The Effect of Body Mass Index on Short-term Outcomes in Patients Undergoing Off-pump Coronary Artery Bypass Grafting Surgery: A Retrospective Study from a Single Cardiovascular Center","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2023-08-11 14:19:16","doi":"10.21203/rs.3.rs-3240589/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2023-11-05T10:27:53+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2023-10-02T16:07:45+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"09256236-9545-488b-8b8d-53dbee1a0c26","date":"2023-09-25T23:16:45+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"70b09c88-2361-49e9-b11b-2e6d0b2d6368","date":"2023-09-25T12:21:00+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2023-09-25T12:06:58+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2023-09-24T17:23:35+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2023-08-08T03:53:41+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Cardiothoracic Surgery","date":"2023-08-07T04:18:22+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-cardiothoracic-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jcts","sideBox":"Learn more about [Journal of Cardiothoracic Surgery](http://cardiothoracicsurgery.biomedcentral.com)","snPcode":"13019","submissionUrl":"https://submission.nature.com/new-submission/13019/3","title":"Journal of Cardiothoracic Surgery","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ee84455b-8998-4cce-a852-fa2513d27634","owner":[],"postedDate":"August 11th, 2023","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-02-12T15:02:24+00:00","versionOfRecord":{"articleIdentity":"rs-3240589","link":"https://doi.org/10.1186/s13019-024-02586-1","journal":{"identity":"journal-of-cardiothoracic-surgery","isVorOnly":false,"title":"Journal of Cardiothoracic Surgery"},"publishedOn":"2024-02-11 15:00:44","publishedOnDateReadable":"February 11th, 2024"},"versionCreatedAt":"2023-08-11 14:19:16","video":"","vorDoi":"10.1186/s13019-024-02586-1","vorDoiUrl":"https://doi.org/10.1186/s13019-024-02586-1","workflowStages":[]},"version":"v1","identity":"rs-3240589","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3240589","identity":"rs-3240589","version":["v1"]},"buildId":"_2-kVJe1T_tPrBINL-cwx","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}