Association Between the Confusion Assessment Method for the Intensive Care Unit (CAM- ICU) and Prolonged Mechanical Ventilation Following Major Cardiac Surgery

Association Between the Confusion Assessment Method for the Intensive Care Unit (CAM- ICU) and Prolonged Mechanical Ventilation Following Major Cardiac Surgery | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Association Between the Confusion Assessment Method for the Intensive Care Unit (CAM- ICU) and Prolonged Mechanical Ventilation Following Major Cardiac Surgery Joon Young Kim, Young Ae Kang, Pil-Je Kang This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7745930/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 21 Jan, 2026 Read the published version in European Journal of Medical Research → Version 1 posted 11 You are reading this latest preprint version Abstract Background Delirium is common after cardiac surgery and has been associated with adverse outcomes in critically ill patients. The Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) is a validated tool for detecting delirium; however, few studies have explored its association with prolonged mechanical ventilation (PMV) following major cardiac surgery. This study aimed to investigate whether a positive CAM-ICU assessment is associated with PMV and other postoperative outcomes in this population. Methods We conducted a retrospective cohort study of 1,437 adult patients who underwent cardiac surgery in 2022. Delirium was assessed daily using the CAM-ICU during the early postoperative period. PMV was defined as ventilation lasting more than 24 hours after surgery. Clinical outcomes were analyzed using logistic regression and time-dependent Cox regression, with adjustments made using inverse probability of treatment weighting (IPTW). Results Among 1,437 patients, 281 (19.6%) were assessed as CAM-ICU positive in the early postoperative period. After IPTW adjustment, a positive CAM-ICU assessment was significantly associated with increased risk of PMV (odds ratio [OR] 3.60; 95% CI, 2.53–5.10; p < 0.001), reintubation (OR 3.37; 95% CI, 1.52–7.31; p = 0.002), intensive care unit (ICU) readmission (OR 2.53; 95% CI, 1.22–5.03; p = 0.010), and prolonged ICU stay after extubation (OR 2.95; 95% CI, 2.19–3.96; p < 0.001). Neither early death nor all-cause mortality differed significantly between groups after IPTW adjustment. Age-related analyses indicated that predicted ventilator duration was generally longer with a positive CAM-ICU assessment across most age groups, with attenuation of this difference in the very elderly (≥ 80 years). Conclusion An early postoperative positive CAM-ICU assessment was associated with higher risks of PMV, reintubation, ICU readmission, and prolonged ICU stay after major cardiac surgery. Routine CAM-ICU screening may help identify patients at risk of prolonged ventilation and enable timely, targeted interventions to improve postoperative respiratory recovery. delirium CAM-ICU prolonged mechanical ventilation cardiac surgery Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 INTRODUCTION Delirium is a common and serious complication among critically ill patients, including those undergoing cardiac surgery. It is associated with adverse outcomes in hospitalized patients, such as prolonged length of stay, an increased likelihood of discharge to institutional care, and elevated mortality rates [ 1 – 3 ]. The Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) is a validated and widely used tool for detecting delirium, particularly in mechanically ventilated patients [ 4 , 5 ]. Prolonged mechanical ventilation (PMV) following major cardiac surgery is a well-recognized risk factor for postoperative complications and mortality [ 6 , 7 ]. Specifically, patients who require mechanical ventilation for 24 hours or more after cardiac surgery exhibit higher mortality rates, and this threshold is widely accepted as a clinically meaningful definition of PMV [ 8 , 9 ]. Identifying patients at risk for PMV in the early postoperative period is important for implementing timely and individualized management strategies that may improve outcomes. Although previous studies have demonstrated associations between delirium and delayed ventilator weaning [ 10 , 11 ], evidence regarding the predictive value of CAM-ICU assessments in the cardiac surgical population remains limited. This study aimed to investigate whether a positive CAM-ICU assessment in the early postoperative period is associated with the risk of PMV and other adverse outcomes in patients undergoing major cardiac surgery. METHODS Study Cohort From the Institutional Cardiac Surgery Database of Asan Medical Center, we identified 2,000 consecutive adult patients (aged ≥18 years) who underwent major cardiac surgery between January and December 2022. Patients were excluded if they (1) did not have a documented CAM-ICU assessment; (2) died within 24 hours after surgery; or (3) were not admitted to the intensive care unit (ICU) postoperatively. Consequently, 1,437 patients were included in the final analysis ( Figure 1 ). ICU Management and Ventilator Weaning Protocol Following Cardiac Surgery Patients were admitted directly to the ICU following surgery. Hemodynamic status was continuously monitored using arterial catheters, and fluid therapy, inotropes, and vasopressors were administered based on the type of surgery and the patient's condition. Mechanical ventilation was initiated in pressure-controlled mode, with an initial tidal volume set at 8–10 mL/kg of predicted body weight, a positive end-expiratory pressure (PEEP) of 5 cmH₂O, a fraction of inspired oxygen (FiO₂) of 0.6, a respiratory rate of 12 breaths/min, and an inspiratory-to-expiratory ratio of 1:2. Ventilator weaning was initiated when patients met all of the following criteria: alert and oriented mental status; adequate spontaneous respiratory effort with a respiratory rate (RR) ≥ the ventilator setting plus 2 breaths/min; tidal volume ≥ 6 mL/kg of predicted body weight; FiO₂ of 0.40; PEEP of 5 cmH₂O; pressure support (PS) level 90 mm Hg and heart rate < 120 beats/min; and total chest tube drainage < 100 mL/h. Extubation was performed after patients successfully tolerated PS mode with an FiO₂ of 0.40, PEEP of 5 cmH₂O, and a PS level of ≤10 cmH₂O for at least 1 hour. The arterial blood gas analysis criteria for extubation included a pH of ≥ 7.3, a PaO₂ of ≥ 70 mm Hg, an SpO₂ of > 95%, and an RR of < 30 breaths/min. All patients were managed in accordance with our center’s standardized ventilator weaning and extubation protocol. Daily delirium screening was performed using a Korean-translated version of the CAM-ICU at least twice every 8 hours throughout the early postoperative period. Data Collection and Clinical Outcomes The primary outcome of interest was PMV, defined as the need for ventilator support lasting more than 24 hours following surgery. Secondary outcomes included early complications that occurred within 30 days of surgery or during the same hospitalization, such as early death, reintubation, ICU readmission, and an ICU stay exceeding 48 hours after extubation. Both ICU readmission and reintubation were defined as any occurrence for any reason after the initial discharge from the ICU or extubation. Clinical follow-up was conducted until December 31, 2024. Survival status and date of death were verified using data from the Korean National Health Insurance Service. Additional clinical data were collected through a comprehensive review of institutional electronic medical records and telephone interviews. Patients who did not experience adverse clinical events were censored at the end of the follow-up period. Statistical Analysis Statistical analyses were performed using R version 4.3.2 (R Foundation for Statistical Computing, Vienna, Austria). Categorical variables, presented as frequencies (%), were compared using the χ² test or Fisher’s exact test. Continuous variables, presented as mean ± standard deviation for normally distributed data or as median (interquartile range) for skewed data, were compared using Student’s unpaired t-test or the Mann–Whitney U test, as appropriate. To mitigate potential confounders and selection biases inherent in observational comparisons, differences between patients who tested positive and negative for CAM-ICU were adjusted using inverse probability of treatment weighting (IPTW) based on propensity scores. Propensity scores were estimated using logistic regression that incorporated baseline demographics, comorbidities, and surgical characteristics ( Table 1 ). Stabilized IPTW with trimming of extreme weights was used to reduce variance and limit the influence of outliers. Covariate balance between exposure groups was assessed using standardized mean differences (SMD), with SMD<0.20 indicating acceptable balance [12]. After adjusting for baseline differences using the IPTW method, logistic regression models were employed to evaluate early postoperative outcomes, with results expressed as odds ratios and 95% confidence intervals. All-cause mortality was analyzed using Cox proportional hazards models with IPTW-adjusted weights. For time-to-event outcomes involving competing risks (e.g., PMV vs. early death), Fine–Gray subdistribution hazard models were applied, treating death as a competing event. Long-term survival was assessed using the Kaplan–Meier method and compared through IPTW-adjusted Cox regression. Subgroup analyses were conducted based on prespecified clinical variables (e.g., age group, sex, renal function, surgical type) to evaluate effect modification. Interaction terms between CAM-ICU status and the subgroups were formally tested within Fine–Gray models. To visualize age-related differences, we modeled ventilator duration by age and CAM-ICU group and plotted adjusted marginal effects (Figure 4). Time-to-extubation curves by CAM-ICU group are displayed in Figure 5. All reported p-values were two-tailed, and outcomes with p-values < 0.05 were deemed statistically significant. RESULTS Baseline Characteristics The mean age of the entire cohort was 60.9 ± 12.8 years, and 550 patients (38.3%) were men. Among the 1,437 patients included in the study, 281 (19.6%) were assessed as CAM-ICU positive during the early postoperative period. Baseline demographic and clinical characteristics are summarized in Table 1 . Patients with a positive CAM-ICU assessment were significantly older than those with a negative CAM-ICU assessment (66.3 ± 11.2 vs. 59.6 ± 12.8 years; p < 0.001). Additionally, the CAM-ICU–positive group had a higher prevalence of comorbidities, including hypertension (64.1% vs. 54.2%; p = 0.004), diabetes mellitus (32.0% vs. 24.4%; p = 0.011), cerebrovascular disease (13.9% vs. 9.4%; p = 0.036), and chronic obstructive pulmonary disease (10.7% vs. 4.5%; p < 0.001). Impaired renal function (estimated glomerular filtration rate [eGFR] <60 mL/min/1.73 m²) was significantly more prevalent in the CAM-ICU–positive group (34.6% vs. 16.0%; p < 0.001). In addition, the CAM-ICU–positive group had a higher proportion of patients who received preoperative mechanical ventilation (3.2% vs. 0.7%; p = 0.001) and extracorporeal membrane oxygenation (3.9% vs. 0.7%; p < 0.001), as well as those who were admitted to the ICU prior to surgery (14.9% vs. 4.8%; p < 0.001). Operative Profiles Operative characteristics are presented in Table 1 . The CAM-ICU–positive group had a higher proportion of those who underwent emergent operations (17.4% vs. 9.5%; p < 0.001) and experienced longer operative times (4.7 ± 1.8 vs. 3.8 ± 1.4 hours; p < 0.001). The distribution of surgical procedures also varied between the groups, with a higher proportion of aortic procedures observed in the CAM-ICU–positive group (23.8% vs. 16.1%; p < 0.001). In contrast, minimally invasive cardiac surgery was more prevalent among the CAM-ICU–negative group (51.7% vs. 34.2%; p < 0.001). Unadjusted Clinical Outcomes The CAM-ICU–positive group had significantly higher rates of adverse outcomes ( Table 2 ), including the incidence of PMV (37.4% vs. 5.4%; odds ratio [OR] 10.52, 95% CI 7.43–15.04; p < 0.001). Other early complications, including early death (3.2% vs. 0.8%; p = 0.003), reintubation (8.2% vs. 1.2%; p < 0.001), ICU readmission (8.5% vs. 1.8%; p < 0.001), and prolonged ICU stay beyond 48 hours after extubation (45.9% vs. 17.1%; p < 0.001), were also significantly more prevalent in the CAM-ICU positive group. Follow-up for all-cause mortality was completed for all patients, with a median follow-up duration of 29.8 months. During this period, deaths occurred in 20 patients (7.1%) with positive CAM-ICU assessments and in 12 patients (1.0%) with negative assessments (p < 0.001). In the unadjusted Cox regression model, a positive CAM-ICU assessment was significantly associated with increased all-cause mortality (hazard ratio [HR], 4.11; 95% CI, 1.63–10.36; p = 0.003) ( Figure 2A ). Adjusted Clinical Outcomes After IPTW adjustment, baseline characteristics—including demographics, comorbidities, and operative profiles—were well balanced, with standardized mean differences of less than 20% across most variables. In the adjusted logistic regression models, a positive CAM-ICU assessment was independently associated with increased risks of PMV (OR 3.60; 95% CI, 2.53–5.10; p < 0.001), reintubation (OR 3.37; 95% CI, 1.52–7.31; p = 0.002), ICU readmission (OR 2.53; 95% CI, 1.22–5.03; p = 0.010), and a prolonged ICU stay beyond 48 hours after extubation (OR 2.95; 95% CI, 2.19–3.96; p < 0.001). In contrast, early postoperative mortality did not significantly differ between the groups (OR 1.13; 95% CI, 0.37–2.86; p = 0.805). Similarly, a positive CAM-ICU assessment was not significantly associated with all-cause mortality in the Cox regression model (HR 1.77; 95% CI, 0.79–3.95; p = 0.164) (Figure 2B) . Subgroup Analysis Subgroup analyses were conducted to evaluate whether the association between a positive CAM-ICU assessment and the risk of PMV varied across predefined clinical subgroups ( Figure 3 ). The increased risk of PMV in patients with a positive CAM-ICU assessment was consistently observed across the majority of subgroups. Although the overall association remained consistent, formal tests for interaction revealed statistically significant effect modification in specific subgroups, including patients aged ≥70 years, those requiring preoperative mechanical ventilation or ECMO support, and those with a history of prior cardiac surgery. In these groups, the relative effect size of a positive CAM-ICU assessment on PMV was diminished compared to their counterparts. Age-related pattern in ventilator duration To further investigate the modifying effect of age, we analyzed the relationship between age and ventilator duration based on the CAM-ICU assessment ( Figure 4 ). In most age groups, patients with a positive CAM-ICU assessment demonstrated longer ventilator durations compared to those with a negative assessment. However, this difference gradually diminished after the age of 70, and beyond 80 years, patients with a negative CAM-ICU assessment experienced longer ventilator durations. Predictors of Prolonged Mechanical Ventilation In the univariate logistic regression analysis, several preoperative and surgical variables were significantly associated with PMV following major cardiac surgery ( Table 3 ). Factors such as older age, chronic obstructive pulmonary disease, eGFR <60 mL/min/1.73 m², lower hemoglobin levels, preoperative mechanical ventilation, a history of ICU admission, and preoperative ECMO support were significantly associated with an increased risk of PMV. Additionally, aortic surgery, a history of prior cardiac surgery, and emergent surgery were also significantly associated with PMV. In contrast, minimally invasive cardiac surgery was associated with a decreased likelihood of PMV. In the multivariable analysis ( Table 4 ), a positive CAM-ICU assessment remained as the strongest independent predictor of PMV (OR 7.35; 95% CI, 4.86–11.22; p < 0.001). Additional risk factors included a higher BMI, impaired renal function, history of cardiac surgery, preoperative mechanical ventilation, aortic surgery, longer operative time, and emergent surgery. Conversely, higher preoperative hemoglobin levels were associated with a reduced risk of PMV. Ventilator Weaning Probability Time-to-event analysis for ventilator weaning revealed a significantly lower probability of successful weaning in patients with a positive CAM-ICU assessment compared to those with a negative assessment ( Figure 5 ). In the CAM-ICU negative group, most patients were successfully weaned from mechanical ventilation within the first 24 hours after surgery, showing a steep early increase in cumulative weaning probability. In contrast, the CAM-ICU positive group showed a delayed and more gradual trajectory of ventilator liberation, with the disparity persisting throughout the 96-hour observation period (p < 0.001). DISCUSSION In this contemporary cohort of patients undergoing major cardiac surgery, we investigated the clinical impact of a positive CAM-ICU assessment on PMV and other early postoperative outcomes. Patients with a positive CAM-ICU assessment experienced significantly higher rates of PMV, reintubation, ICU readmission, and extended ICU stays beyond 48 hours following extubation. These associations remained robust after adjustment using IPTW, underscoring the independent prognostic value of a positive early postoperative CAM-ICU assessment. Our findings are consistent with prior studies reporting that delirium is associated with adverse respiratory outcomes in critically ill populations [ 9 , 13 ]. A positive CAM-ICU assessment was a significant predictor of PMV in our multivariable analysis. This may reflect the combined effects of impaired cognition, reduced patient cooperation, and the need for deeper or prolonged sedation—factors known to hinder successful ventilator weaning [ 14 , 15 ]. Additionally, the rates of reintubation and ICU readmission were higher among patients with a positive CAM-ICU assessment, further highlighting the detrimental impact of early postoperative delirium on recovery. In contrast to previous studies that reported a significant association between delirium and mortality in ICU populations [ 18 , 19 ], we found no statistically significant association between a positive CAM-ICU assessment and either early or all-cause mortality after IPTW adjustment. While unadjusted comparisons showed higher mortality among patients with a positive CAM-ICU assessment, this effect disappeared after accounting for preoperative risk factors. Several explanations are plausible. First, our study population predominantly consisted of patients undergoing elective or semi-urgent procedures with relative hemodynamic stability, with only 11.1% of patients requiring emergent operations. This contrasts with general ICU cohorts experiencing sepsis or multiorgan failure, where delirium often reflects more severe systemic illness. Second, the relatively low mortality rate and limited follow-up duration in our cohort may have reduced the statistical power to detect significant long-term differences. These outcomes may also be influenced by consistent perioperative management practices at our high-volume tertiary center, including adherence to standardized protocols and the involvement of experienced multidisciplinary teams. Subgroup analyses revealed that the association between a positive CAM-ICU assessment and PMV was attenuated in certain high-risk groups, including patients aged ≥ 70 years, those requiring preoperative mechanical ventilation or ECMO support, and those with a history of cardiac surgery. These factors may serve as significant predictors of PMV [ 16 , 17 ], thereby reducing the relative impact of a positive CAM-ICU assessment. Age-stratified modeling indicated that ventilator duration was generally longer with a positive CAM-ICU assessment across most age groups, with attenuation after age 70 and a possible reversal among patients aged ≥ 80 years. Among the 18 early deaths in the cohort, 12 occurred in patients aged ≥ 70 years (6 in each CAM-ICU group), suggesting that early mortality may have limited the opportunity for prolonged ventilator support, particularly in elderly patients. Moreover, the apparent reversal in patients over 80 years may be partly attributable to statistical variability resulting from the small sample size (n = 55), which limits the reliability of subgroup estimates. From a clinical perspective, early screening with the CAM-ICU tool may help identify patients at an elevated risk of respiratory complications following cardiac surgery. In our multivariable model, additional predictors of PMV included higher BMI, impaired renal function, history of cardiac surgery, low preoperative hemoglobin levels, preoperative ventilator use, aortic procedures, longer operative times, and emergent operations. Recognizing these risk factors could facilitate early intervention and optimize resource allocation. Institution-level strategies to prevent and manage postoperative delirium—such as early mobilization, environmental optimization, and the minimization of deliriogenic medications—should be prioritized [ 20 ]. Certain patients may also benefit from pharmacologic interventions, including dexmedetomidine [ 21 ]. Special attention is warranted for older adults with a positive CAM-ICU assessment, as they are at an increased risk for PMV and related complications. LIMITATIONS This study has several limitations. First, as a retrospective, single-center analysis, it may be subject to selection biases that could not be fully addressed through statistical adjustments. Second, our cohort was confined to a single high-volume tertiary center, which may limit the generalizability of the findings to other practice settings. Third, CAM-ICU performance can be reduced in deeply sedated or hypoactive patients, potentially leading to under-detection; moreover, delirium severity, duration, and motor subtype were not captured and could modify risk estimates. Fourth, we did not assess patient-centered outcomes such as cognitive function, physical disability, or quality of life, which are increasingly emphasized in delirium research. Fifth, the overall mortality rate was low and the follow-up period may have been insufficient to detect modest long-term differences in survival. Finally, subgroup results—particularly for patients aged ≥ 80 years—should be interpreted with caution given small sample sizes, limited precision of age-interaction estimates, and the attendant risk of type II error. CONCLUSION A positive CAM-ICU assessment in the early postoperative period was associated with an increased risk of prolonged mechanical ventilation, reintubation, ICU readmission, and extended ICU stays among patients undergoing major cardiac surgery. Predicted ventilator duration was generally longer with a positive CAM-ICU assessment across most age groups, with attenuation in the very elderly. Routine CAM-ICU screening may help identify patients at risk of prolonged ventilation and enable timely, targeted interventions to improve postoperative respiratory recovery. Abbreviations CAM-ICU: Confusion Assessment Method for the Intensive Care Unit PMV: Prolonged mechanical ventilation ICU: Intensive care unit PEEP: Positive end-expiratory pressure FiO 2 : Fraction of inspired oxygen RR: Respiratory rate PS: Pressure support IPTW: Inverse-probability-of-treatment weighting SMD: Standardized mean differences eGFR: Estimated glomerular filtration rate OR: Odds ratio HR: Hazard ratio Declarations Acknowledgements Not applicable. Author Contribution JYK was responsible for the methodology, data curation, formal analysis, visualization, and drafting the original manuscript. YAK contributed to data curation and the drafting of the original manuscript. PJK supervised the study, managed the project, and critically revised the manuscript. Funding There are no funding sources to declare. Availability of data and materials The datasets generated and/or analyzed during the current study are available from the corresponding author upon reasonable request. Ethics approval and consent to participate This study was conducted in accordance with the principles of the Declaration of Helsinki. The study protocol was approved by the Institutional Review Board of Asan Medical Center (Study no: 2025-0623; Date of approval: May 22, 2025). The requirement for informed consent was waived due to the observational nature of the study. Consent for publication Not applicable. Competing interests The authors declare no competing interests. References Salluh JI, Wang H, Schneider EB, Nagaraja N, Yenokyan G, Damluji A, Serafim RB, Stevens RD: Outcome of delirium in critically ill patients: systematic review and meta-analysis . BMJ 2015, 350 :h2538. Chen H, Mo L, Hu H, Ou Y, Luo J: Risk factors of postoperative delirium after cardiac surgery: a meta-analysis . J Cardiothorac Surg 2021, 16 (1):113. Mattimore D, Fischl A, Christophides A, Cuenca J, Davidson S, Jin Z, Bergese S: Delirium after Cardiac Surgery-A Narrative Review . Brain Sci 2023, 13 (12). 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Duan X, Coburn M, Rossaint R, Sanders RD, Waesberghe JV, Kowark A: Efficacy of perioperative dexmedetomidine on postoperative delirium: systematic review and meta-analysis with trial sequential analysis of randomised controlled trials . Br J Anaesth 2018, 121 (2):384-397. Tables Table 1. Baseline characteristics and operative profiles according to the CAM-ICU status in the unadjusted and IPTW-adjusted cohorts Original IPTW-adjusted Variables CAM-ICU (-) (N=1156) CAM-ICU (+) (N=281) p-value SMD CAM-ICU (-) (N=1156) CAM-ICU (+) (N=281) p-value SMD Age (years) 59.6 ± 12.8 66.3 ± 11.2 <0.001 55.5% 61.1 ± 12.8 60.6 ± 12.8 0.718 3.8% Female 429 (37.1) 121 (43.1) 0.076 12.2% 439 (38.0) 104 (37.0) 0.820 2.0% BMI (kg/m 2 ) 24.2 ± 3.5 24.0 ± 4.3 0.494 4.8% 24.1 ± 3.5 24.2 ± 4.4 0.785 2.6% Hypertension 627 (54.2) 180 (64.1) 0.004 20.1% 645 (55.8) 163 (57.9) 0.630 4.3% Diabetes mellitus 282 (24.4) 90 (32.0) 0.011 17.0% 302 (26.2) 77 (27.3) 0.755 2.5% Cerebrovascular disease 109 (9.4) 39 (13.9) 0.036 13.9% 124 (10.8) 31 (11.1) 0.881 1.2% COPD 52 (4.5) 30 (10.7) <0.001 43.9% 70 (6.0) 15 (5.3) 0.614 3.3% eGFR (mL/min/1.73 ) <0.001 43.9% 0.883 3.1% 60 972 (84.1) 184 (65.5) 930 (80.5) 230 (81.7) History of cardiac surgery 164 (14.2) 67 (23.8) <0.001 24.8% 192 (16.6) 46 (16.3) 0.910 0.9% Hemoglobin (g/dL) 12.8 ± 1.9 11.9 ± 2.2 <0.001 44.7% 12.6 ± 2.0 12.7 ± 2.1 0.487 6.0% PMV 8 (0.7) 9 (3.2) 0.001 18.2% 17 (1.5) 4 (1.3) 0.815 1.4% History of ICU admission 55 (4.8) 42 (14.9) <0.001 34.7% 78 (6.8) 18 (6.3) 0.749 2.0% Preoperative ECMO support 8 (0.7) 11 (3.9) <0.001 21.6% 17 (1.5) 4 (1.4) 0.890 0.8% Operative profile Operation type 0.002 28.0% 0.979 7.7% Valve 624 (54.0) 129 (45.9) 602 (52.1) 143 (50.8) CABG 184 (15.9) 48 (17.1) 186 (16.1) 53 (18.8) Aorta 95 (8.2) 40 (14.2) 117 (10.1) 29 (10.3) Valve + CABG 39 (3.4) 16 (5.7) 43 (3.7) 10 (3.6) Valve + Aorta 88 (7.6) 23 (8.2) 92 (8.0) 21 (7.4) CABG + Aorta 3 (0.3) 3 (1.1) 4 (0.3) 1 (0.4) Others 123 (10.6) 22 (7.8) 113 (9.7) 25 (8.8) Operative time, hours 3.8 ± 1.4 4.7 ± 1.8 <0.001 59.6% 4.0 ± 1.7 4.0 ± 1.5 0.562 4.9% MICS 598 (51.7) 96 (34.2) <0.001 36.1% 551 (47.7) 132 (46.9) 0.862 1.5% Emergent operation 110 (9.5) 49 (17.4) <0.001 23.4% 134 (11.6) 28 (9.9) 0.459 5.3% ICU stay (days) 1 (1–2) 3 (2–8) <0.001 54.6% 1 (1–2) 2 (1–4) <0.001 27.5% Hospital stay (days) 8 (7–12) 14 (9–36) 0.023 9.5% 9 (7–13) 10 (8–21) 0.302 9.6% Values are presented as n (%), mean ± standard deviation, or median (interquartile range: Q1–Q3), unless otherwise specified. IPTW, Inverse-probability-of-treatment weighting; SMD, Standardized mean difference; BMI, Body mass index; COPD, Chronic obstructive pulmonary disease; eGFR, Estimated glomerular filtration rate; PMV, Preoperative mechanical ventilation; ICU, Intensive care unit; ECMO, Extracorporeal membrane oxygenation; CABG, Coronary artery bypass graft surgery; MICS, Minimally invasive cardiac surgery Table 2. Early and overall clinical outcomes according to the CAM-ICU status in the unadjusted and IPTW-adjusted cohorts Original IPTW-adjusted No. of events (rate) Outcomes CAM-ICU (-) (N=1156) CAM-ICU (+) (N=281) OR or HR (95% CI) p-value OR or HR (95% CI) p-value Early Outcomes Prolonged ventilation > 24 hours 62 (5.4) 105 (37.4) 10.52 (7.43–15.04) <0.001 3.60 (2.53–5.10) <0.001 Early death 9 (0.8) 9 (3.2) 4.21 (1.67–10.60) 0.003 1.13 (0.37–2.86) 0.805 Reintubation 14 (1.2) 23 (8.2) 7.27 (3.73–14.66) <0.001 3.37 (1.52–7.31) 0.002 ICU readmission 21 (1.8) 24 (8.5) 5.05 (2.77–9.28) 48 hr) 198 (17.1) 129 (45.9) 4.10 (3.10–5.44) <0.001 2.95 (2.19–3.96) <0.001 Overall Outcomes All-cause death 12 (1.0) 20 (7.1) 4.11 (1.63–10.36) 0.003 1.77 (0.79–3.95) 0.164 Values are presented as n (%). Odds ratios and hazard ratios are presented for early outcomes and overall outcomes, respectively. OR, Odds ratio; HR, Hazard ratio; CI, Confidence interval; IPTW, Inverse-probability-of-treatment weighting; ICU, Intensive care unit Table 3. Univariable logistic regression for predictors of prolonged mechanical ventilation after major cardiac surgery Variables OR (95% CI) p-value Age 1.03 (1.01–1.04) <0.001 Female sex 1.22 (0.88–1.69) 0.231 BMI 1.02 (0.97–1.06) 0.418 Hypertension 1.33 (0.96–1.86) 0.091 Diabetes mellitus 1.38 (0.97–1.96) 0.067 Cerebrovascular disease 1.29 (0.77–2.08) 0.305 COPD 2.28 (1.28–3.87) 0.003 eGFR <30 mL/min/1.73 5.29 (3.07–8.91) <0.001 30–60 mL/min/1.73 2.98 (2.01–4.38) 60 mL/min/1.73 Reference History of cardiac surgery 4.10 (2.88–5.82) <0.001 Hemoglobin 0.73 (0.67–0.79) <0.001 Preoperative mechanical ventilation 19.59 (7.16–62.24) <0.001 History of ICU admission 8.21 (5.27–12.76) <0.001 Preoperative ECMO support 17.78 (6.92–51.24) <0.001 CAM-ICU 10.53 (7.43–15.04) <0.001 Operative profile Operation type Valve Reference CABG 0.70 (0.39–1.20) 0.215 Aorta 3.18 (2.00–5.01) <0.001 Valve + CABG 0.74 (0.22–1.88) 0.576 Valve + Aorta 2.21 (1.27–3.71) 0.004 CABG + Aorta 4.72 (0.65–24.67) 0.757 Others 1.34 (0.75–2.28) 0.296 Operative time 1.89 (1.70–2.10) <0.001 MICS 1.74 (0.89-3.39) 0.105 Emergent operation 5.93 (4.05–8.65) <0.001 OR, Odds ratio; CI, Confidence interval; BMI, Body mass index; COPD, Chronic obstructive pulmonary disease; eGFR, Estimated glomerular filtration rate; ICU, Intensive care unit; ECMO, Extracorporeal membrane oxygenation; CABG, Coronary artery bypass graft surgery; MICS, Minimally invasive cardiac surgery. Table 4. Multivariable logistic regression for predictors of prolonged mechanical ventilation after major cardiac surgery Variables OR (95% CI) P-value BMI 1.07 (1.01–1.12) 0.015 eGFR 60 mL/min/1.73 Reference History of cardiac surgery 2.27 (1.43–3.57) <0.001 Hemoglobin 0.87 (0.78–0.96) 0.007 Preoperative mechanical ventilation 6.70 (2.02–24.94) 0.003 CAM-ICU 7.35 (4.86–11.22) <0.001 Operative profile Aortic surgery 1.85 (1.14–2.96) 0.011 Operative time 1.55 (1.37–1.75) <0.001 Emergent operation 3.40 (2.02–5.70) <0.001 Candidate covariates were initially screened with univariable analyses ( Table 3 ). Clinically significant covariates with a p value lower than 0.10 in univariable models were used in the multivariable model. Covariates that remained in the multivariable model using the backward elimination technique were retained in the multivariable model. OR, Odds ratio; CI, Confidence interval; BMI, Body mass index; eGFR, Estimated glomerular filtration rate; CAM-ICU, Confusion assessment method for the intensive care unit. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 21 Jan, 2026 Read the published version in European Journal of Medical Research → Version 1 posted Editorial decision: Revision requested 25 Oct, 2025 Reviews received at journal 25 Oct, 2025 Reviews received at journal 19 Oct, 2025 Reviewers agreed at journal 19 Oct, 2025 Reviewers agreed at journal 16 Oct, 2025 Reviews received at journal 15 Oct, 2025 Reviewers agreed at journal 14 Oct, 2025 Reviewers invited by journal 13 Oct, 2025 Editor assigned by journal 06 Oct, 2025 Submission checks completed at journal 06 Oct, 2025 First submitted to journal 29 Sep, 2025 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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1","display":"","copyAsset":false,"role":"figure","size":198256,"visible":true,"origin":"","legend":"\u003cp\u003eFlowchart of study patients\u003c/p\u003e","description":"","filename":"Figure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7745930/v1/754d4ae519ab3d199b60e441.jpg"},{"id":94474333,"identity":"e6346bd7-43e8-4db9-85d9-16fc6b7e4805","added_by":"auto","created_at":"2025-10-27 15:48:27","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":139223,"visible":true,"origin":"","legend":"\u003cp\u003eKaplan–Meier Curves for All-Cause Mortality According to CAM-ICU Assessment in Unadjusted (Panel A) and IPTW-Adjusted (Panel B) Cohorts\u003c/p\u003e","description":"","filename":"Figure2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7745930/v1/20835185345d0f5b828026bd.jpg"},{"id":94474830,"identity":"b30e2544-1cac-4e5b-b4d1-f8e9d3d18a64","added_by":"auto","created_at":"2025-10-27 15:50:17","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":274668,"visible":true,"origin":"","legend":"\u003cp\u003eSubdistribution Hazard Ratios for Prolonged Mechanical Ventilation Associated with a Positive CAM-ICU Assessment in Prespecified Subgroups. COPD, chronic obstructive pulmonary disease; eGFR, estimated glomerular filtration rate; ECMO, extracorporeal membrane oxygenation.\u003c/p\u003e","description":"","filename":"Figure3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7745930/v1/3e36ad2edc439d070f068369.jpg"},{"id":94474105,"identity":"bfc62907-dbc4-4af1-b000-88e8cd65c9ee","added_by":"auto","created_at":"2025-10-27 15:47:26","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":186933,"visible":true,"origin":"","legend":"\u003cp\u003eRelationship Between Age and Ventilator Duration Stratified by CAM-ICU Assessment\u003c/p\u003e","description":"","filename":"Figure4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7745930/v1/5809bf5cc4589e9fe4082280.jpg"},{"id":94474352,"identity":"09db7375-a3d8-4a1a-ad83-b73a338cf9c0","added_by":"auto","created_at":"2025-10-27 15:48:33","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":178071,"visible":true,"origin":"","legend":"\u003cp\u003eTime-to-Event Curves for Ventilator Weaning Stratified by CAM-ICU Assessment\u003c/p\u003e","description":"","filename":"Figure5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7745930/v1/08f49a2cf7f58c2c0950f4df.jpg"},{"id":101151927,"identity":"17be0c88-6af6-4baa-bc1c-468ef56c2a07","added_by":"auto","created_at":"2026-01-26 16:08:23","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2944395,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7745930/v1/c9309fca-1d65-4d6d-8af0-ed46da2a58a4.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Association Between the Confusion Assessment Method for the Intensive Care Unit (CAM- ICU) and Prolonged Mechanical Ventilation Following Major Cardiac Surgery","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eDelirium is a common and serious complication among critically ill patients, including those undergoing cardiac surgery. It is associated with adverse outcomes in hospitalized patients, such as prolonged length of stay, an increased likelihood of discharge to institutional care, and elevated mortality rates [\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. The Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) is a validated and widely used tool for detecting delirium, particularly in mechanically ventilated patients [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eProlonged mechanical ventilation (PMV) following major cardiac surgery is a well-recognized risk factor for postoperative complications and mortality [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Specifically, patients who require mechanical ventilation for 24 hours or more after cardiac surgery exhibit higher mortality rates, and this threshold is widely accepted as a clinically meaningful definition of PMV [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Identifying patients at risk for PMV in the early postoperative period is important for implementing timely and individualized management strategies that may improve outcomes. Although previous studies have demonstrated associations between delirium and delayed ventilator weaning [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e], evidence regarding the predictive value of CAM-ICU assessments in the cardiac surgical population remains limited.\u003c/p\u003e\u003cp\u003eThis study aimed to investigate whether a positive CAM-ICU assessment in the early postoperative period is associated with the risk of PMV and other adverse outcomes in patients undergoing major cardiac surgery.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cp\u003e\u003cstrong\u003eStudy Cohort\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFrom the Institutional Cardiac Surgery Database of Asan Medical Center, we identified 2,000 consecutive adult patients (aged ≥18 years) who underwent major cardiac surgery between January and December 2022. Patients were excluded if they (1) did not have a documented CAM-ICU assessment; (2) died within 24 hours after surgery; or (3) were not admitted to the intensive care unit (ICU) postoperatively. Consequently, 1,437 patients were included in the final analysis (\u003cstrong\u003eFigure 1\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eICU Management and Ventilator Weaning Protocol Following Cardiac Surgery\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePatients were admitted directly to the ICU following surgery. Hemodynamic status was continuously monitored using arterial catheters, and fluid therapy, inotropes, and vasopressors were administered based on the type of surgery and the patient's condition. Mechanical ventilation was initiated in pressure-controlled mode, with an initial tidal volume set at 8–10 mL/kg of predicted body weight, a positive end-expiratory pressure (PEEP) of 5 cmH₂O, a fraction of inspired oxygen (FiO₂) of 0.6, a respiratory rate of 12 breaths/min, and an inspiratory-to-expiratory ratio of 1:2.\u003c/p\u003e\n\u003cp\u003eVentilator weaning was initiated when patients met all of the following criteria: alert and oriented mental status; adequate spontaneous respiratory effort with a respiratory rate (RR) ≥ the ventilator setting plus 2 breaths/min; tidal volume ≥ 6 mL/kg of predicted body weight; FiO₂ of 0.40; PEEP of 5 cmH₂O; pressure support (PS) level \u0026lt; 15 cmH₂O; hemodynamic stability, defined as systolic blood pressure \u0026gt; 90 mm Hg and heart rate \u0026lt; 120 beats/min; and total chest tube drainage \u0026lt; 100 mL/h.\u003c/p\u003e\n\u003cp\u003eExtubation was performed after patients successfully tolerated PS mode with an FiO₂ of 0.40, PEEP of 5 cmH₂O, and a PS level of ≤10 cmH₂O for at least 1 hour. The arterial blood gas analysis criteria for extubation included a pH of ≥ 7.3, a PaO₂ of ≥ 70 mm Hg, an SpO₂ of \u0026gt; 95%, and an RR of \u0026lt; 30 breaths/min. All patients were managed in accordance with our center’s standardized ventilator weaning and extubation protocol. Daily delirium screening was performed using a Korean-translated version of the CAM-ICU at least twice every 8 hours throughout the early postoperative period.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Collection and Clinical Outcomes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe primary outcome of interest was PMV, defined as the need for ventilator support lasting more than 24 hours following surgery. Secondary outcomes included early complications that occurred within 30 days of surgery or during the same hospitalization, such as early death, reintubation, ICU readmission, and an ICU stay exceeding 48 hours after extubation. Both ICU readmission and reintubation were defined as any occurrence for any reason after the initial discharge from the ICU or extubation.\u003c/p\u003e\n\u003cp\u003eClinical follow-up was conducted until December 31, 2024. Survival status and date of death were verified using data from the Korean National Health Insurance Service. Additional clinical data were collected through a comprehensive review of institutional electronic medical records and telephone interviews. Patients who did not experience adverse clinical events were censored at the end of the follow-up period.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eStatistical analyses were performed using R version 4.3.2 (R Foundation for Statistical Computing, Vienna, Austria). Categorical variables, presented as frequencies (%), were compared using the χ² test or Fisher’s exact test. Continuous variables, presented as mean ± standard deviation for normally distributed data or as median (interquartile range) for skewed data, were compared using Student’s unpaired t-test or the Mann–Whitney U test, as appropriate.\u003c/p\u003e\n\u003cp\u003eTo mitigate potential confounders and selection biases inherent in observational comparisons, differences between patients who tested positive and negative for CAM-ICU were adjusted using inverse probability of treatment weighting (IPTW) based on propensity scores. Propensity scores were estimated using logistic regression that incorporated baseline demographics, comorbidities, and surgical characteristics (\u003cstrong\u003eTable 1\u003c/strong\u003e). Stabilized IPTW with trimming of extreme weights was used to reduce variance and limit the influence of outliers. Covariate balance between exposure groups was assessed using standardized mean differences (SMD), with SMD\u0026lt;0.20 indicating acceptable balance [12].\u003c/p\u003e\n\u003cp\u003eAfter adjusting for baseline differences using the IPTW method, logistic regression models were employed to evaluate early postoperative outcomes, with results expressed as odds ratios and 95% confidence intervals. All-cause mortality was analyzed using Cox proportional hazards models with IPTW-adjusted weights. For time-to-event outcomes involving competing risks (e.g., PMV vs. early death), Fine–Gray subdistribution hazard models were applied, treating death as a competing event. Long-term survival was assessed using the Kaplan–Meier method and compared through IPTW-adjusted Cox regression.\u003c/p\u003e\n\u003cp\u003eSubgroup analyses were conducted based on prespecified clinical variables (e.g., age group, sex, renal function, surgical type) to evaluate effect modification. Interaction terms between CAM-ICU status and the subgroups were formally tested within Fine–Gray models. To visualize age-related differences, we modeled ventilator duration by age and CAM-ICU group and plotted adjusted marginal effects (Figure 4). Time-to-extubation curves by CAM-ICU group are displayed in Figure 5. All reported p-values were two-tailed, and outcomes with p-values \u0026lt; 0.05 were deemed statistically significant.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003e\u003cstrong\u003eBaseline Characteristics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe mean age of the entire cohort was 60.9 ± 12.8 years, and 550 patients (38.3%) were men. Among the 1,437 patients included in the study, 281 (19.6%) were assessed as CAM-ICU positive during the early postoperative period. Baseline demographic and clinical characteristics are summarized in \u003cstrong\u003eTable 1\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003ePatients with a positive CAM-ICU assessment were significantly older than those with a negative CAM-ICU assessment (66.3 ± 11.2 vs. 59.6 ± 12.8 years; p \u0026lt; 0.001). Additionally, the CAM-ICU–positive group had a higher prevalence of comorbidities, including hypertension (64.1% vs. 54.2%; p = 0.004), diabetes mellitus (32.0% vs. 24.4%; p = 0.011), cerebrovascular disease (13.9% vs. 9.4%; p = 0.036), and chronic obstructive pulmonary disease (10.7% vs. 4.5%; p \u0026lt; 0.001).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eImpaired renal function (estimated glomerular filtration rate [eGFR] \u0026lt;60 mL/min/1.73 m²) was significantly more prevalent in the CAM-ICU–positive group (34.6% vs. 16.0%; p \u0026lt; 0.001). In addition, the CAM-ICU–positive group had a higher proportion of patients who received preoperative mechanical ventilation (3.2% vs. 0.7%; p = 0.001) and extracorporeal membrane oxygenation (3.9% vs. 0.7%; p \u0026lt; 0.001), as well as those who were admitted to the ICU prior to surgery (14.9% vs. 4.8%; p \u0026lt; 0.001).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eOperative Profiles\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOperative characteristics are presented in \u003cstrong\u003eTable 1\u003c/strong\u003e. The CAM-ICU–positive group had a higher proportion of those who underwent emergent operations (17.4% vs. 9.5%; p \u0026lt; 0.001) and experienced longer operative times (4.7 ± 1.8 vs. 3.8 ± 1.4 hours; p \u0026lt; 0.001). The distribution of surgical procedures also varied between the groups, with a higher proportion of aortic procedures observed in the CAM-ICU–positive group (23.8% vs. 16.1%; p \u0026lt; 0.001). In contrast, minimally invasive cardiac surgery was more prevalent among the CAM-ICU–negative group (51.7% vs. 34.2%; p \u0026lt; 0.001).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eUnadjusted Clinical Outcomes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe CAM-ICU–positive group had significantly higher rates of adverse outcomes (\u003cstrong\u003eTable 2\u003c/strong\u003e), including the incidence of PMV (37.4% vs. 5.4%; odds ratio [OR] 10.52, 95% CI 7.43–15.04; p \u0026lt; 0.001). Other early complications, including early death (3.2% vs. 0.8%; p = 0.003), reintubation (8.2% vs. 1.2%; p \u0026lt; 0.001), ICU readmission (8.5% vs. 1.8%; p \u0026lt; 0.001), and prolonged ICU stay beyond 48 hours after extubation (45.9% vs. 17.1%; p \u0026lt; 0.001), were also significantly more prevalent in the CAM-ICU positive group.\u003c/p\u003e\n\u003cp\u003eFollow-up for all-cause mortality was completed for all patients, with a median follow-up duration of 29.8 months. During this period, deaths occurred in 20 patients (7.1%) with positive CAM-ICU assessments and in 12 patients (1.0%) with negative assessments (p \u0026lt; 0.001). In the unadjusted Cox regression model, a positive CAM-ICU assessment was significantly associated with increased all-cause mortality (hazard ratio [HR], 4.11; 95% CI, 1.63–10.36; p = 0.003) (\u003cstrong\u003eFigure 2A\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAdjusted Clinical Outcomes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAfter IPTW adjustment, baseline characteristics—including demographics, comorbidities, and operative profiles—were well balanced, with standardized mean differences of less than 20% across most variables. In the adjusted logistic regression models, a positive CAM-ICU assessment was independently associated with increased risks of PMV (OR 3.60; 95% CI, 2.53–5.10; p \u0026lt; 0.001), reintubation (OR 3.37; 95% CI, 1.52–7.31; p = 0.002), ICU readmission (OR 2.53; 95% CI, 1.22–5.03; p = 0.010), and a prolonged ICU stay beyond 48 hours after extubation (OR 2.95; 95% CI, 2.19–3.96; p \u0026lt; 0.001).\u003c/p\u003e\n\u003cp\u003eIn contrast, early postoperative mortality did not significantly differ between the groups (OR 1.13; 95% CI, 0.37–2.86; p = 0.805). Similarly, a positive CAM-ICU assessment was not significantly associated with all-cause mortality in the Cox regression model (HR 1.77; 95% CI, 0.79–3.95; p = 0.164) \u003cstrong\u003e(Figure 2B)\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSubgroup Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSubgroup analyses were conducted to evaluate whether the association between a positive CAM-ICU assessment and the risk of PMV varied across predefined clinical subgroups (\u003cstrong\u003eFigure 3\u003c/strong\u003e). The increased risk of PMV in patients with a positive CAM-ICU assessment was consistently observed across the majority of subgroups.\u003c/p\u003e\n\u003cp\u003eAlthough the overall association remained consistent, formal tests for interaction revealed statistically significant effect modification in specific subgroups, including patients aged ≥70 years, those requiring preoperative mechanical ventilation or ECMO support, and those with a history of prior cardiac surgery. In these groups, the relative effect size of a positive CAM-ICU assessment on PMV was diminished compared to their counterparts.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAge-related pattern in ventilator duration\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo further investigate the modifying effect of age, we analyzed the relationship between age and ventilator duration based on the CAM-ICU assessment (\u003cstrong\u003eFigure 4\u003c/strong\u003e). In most age groups, patients with a positive CAM-ICU assessment demonstrated longer ventilator durations compared to those with a negative assessment. However, this difference gradually diminished after the age of 70, and beyond 80 years, patients with a negative CAM-ICU assessment experienced longer ventilator durations.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePredictors of Prolonged Mechanical Ventilation\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn the univariate logistic regression analysis, several preoperative and surgical variables were significantly associated with PMV following major cardiac surgery (\u003cstrong\u003eTable 3\u003c/strong\u003e). Factors such as older age, chronic obstructive pulmonary disease, eGFR \u0026lt;60 mL/min/1.73 m², lower hemoglobin levels, preoperative mechanical ventilation, a history of ICU admission, and preoperative ECMO support were significantly associated with an increased risk of PMV. Additionally, aortic surgery, a history of prior cardiac surgery, and emergent surgery were also significantly associated with PMV. In contrast, minimally invasive cardiac surgery was associated with a decreased likelihood of PMV.\u003c/p\u003e\n\u003cp\u003eIn the multivariable analysis (\u003cstrong\u003eTable 4\u003c/strong\u003e), a positive CAM-ICU assessment remained as the strongest independent predictor of PMV (OR 7.35; 95% CI, 4.86–11.22; p \u0026lt; 0.001). Additional risk factors included a higher BMI, impaired renal function, history of cardiac surgery, preoperative mechanical ventilation, aortic surgery, longer operative time, and emergent surgery. Conversely, higher preoperative hemoglobin levels were associated with a reduced risk of PMV.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eVentilator Weaning Probability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTime-to-event analysis for ventilator weaning revealed a significantly lower probability of successful weaning in patients with a positive CAM-ICU assessment compared to those with a negative assessment (\u003cstrong\u003eFigure 5\u003c/strong\u003e). In the CAM-ICU negative group, most patients were successfully weaned from mechanical ventilation within the first 24 hours after surgery, showing a steep early increase in cumulative weaning probability. In contrast, the CAM-ICU positive group showed a delayed and more gradual trajectory of ventilator liberation, with the disparity persisting throughout the 96-hour observation period (p \u0026lt; 0.001).\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eIn this contemporary cohort of patients undergoing major cardiac surgery, we investigated the clinical impact of a positive CAM-ICU assessment on PMV and other early postoperative outcomes. Patients with a positive CAM-ICU assessment experienced significantly higher rates of PMV, reintubation, ICU readmission, and extended ICU stays beyond 48 hours following extubation. These associations remained robust after adjustment using IPTW, underscoring the independent prognostic value of a positive early postoperative CAM-ICU assessment.\u003c/p\u003e\u003cp\u003eOur findings are consistent with prior studies reporting that delirium is associated with adverse respiratory outcomes in critically ill populations [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. A positive CAM-ICU assessment was a significant predictor of PMV in our multivariable analysis. This may reflect the combined effects of impaired cognition, reduced patient cooperation, and the need for deeper or prolonged sedation\u0026mdash;factors known to hinder successful ventilator weaning [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Additionally, the rates of reintubation and ICU readmission were higher among patients with a positive CAM-ICU assessment, further highlighting the detrimental impact of early postoperative delirium on recovery.\u003c/p\u003e\u003cp\u003eIn contrast to previous studies that reported a significant association between delirium and mortality in ICU populations [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e], we found no statistically significant association between a positive CAM-ICU assessment and either early or all-cause mortality after IPTW adjustment. While unadjusted comparisons showed higher mortality among patients with a positive CAM-ICU assessment, this effect disappeared after accounting for preoperative risk factors. Several explanations are plausible. First, our study population predominantly consisted of patients undergoing elective or semi-urgent procedures with relative hemodynamic stability, with only 11.1% of patients requiring emergent operations. This contrasts with general ICU cohorts experiencing sepsis or multiorgan failure, where delirium often reflects more severe systemic illness. Second, the relatively low mortality rate and limited follow-up duration in our cohort may have reduced the statistical power to detect significant long-term differences. These outcomes may also be influenced by consistent perioperative management practices at our high-volume tertiary center, including adherence to standardized protocols and the involvement of experienced multidisciplinary teams.\u003c/p\u003e\u003cp\u003eSubgroup analyses revealed that the association between a positive CAM-ICU assessment and PMV was attenuated in certain high-risk groups, including patients aged\u0026thinsp;\u0026ge;\u0026thinsp;70 years, those requiring preoperative mechanical ventilation or ECMO support, and those with a history of cardiac surgery. These factors may serve as significant predictors of PMV [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e], thereby reducing the relative impact of a positive CAM-ICU assessment.\u003c/p\u003e\u003cp\u003eAge-stratified modeling indicated that ventilator duration was generally longer with a positive CAM-ICU assessment across most age groups, with attenuation after age 70 and a possible reversal among patients aged\u0026thinsp;\u0026ge;\u0026thinsp;80 years. Among the 18 early deaths in the cohort, 12 occurred in patients aged\u0026thinsp;\u0026ge;\u0026thinsp;70 years (6 in each CAM-ICU group), suggesting that early mortality may have limited the opportunity for prolonged ventilator support, particularly in elderly patients. Moreover, the apparent reversal in patients over 80 years may be partly attributable to statistical variability resulting from the small sample size (n\u0026thinsp;=\u0026thinsp;55), which limits the reliability of subgroup estimates.\u003c/p\u003e\u003cp\u003eFrom a clinical perspective, early screening with the CAM-ICU tool may help identify patients at an elevated risk of respiratory complications following cardiac surgery. In our multivariable model, additional predictors of PMV included higher BMI, impaired renal function, history of cardiac surgery, low preoperative hemoglobin levels, preoperative ventilator use, aortic procedures, longer operative times, and emergent operations. Recognizing these risk factors could facilitate early intervention and optimize resource allocation.\u003c/p\u003e\u003cp\u003eInstitution-level strategies to prevent and manage postoperative delirium\u0026mdash;such as early mobilization, environmental optimization, and the minimization of deliriogenic medications\u0026mdash;should be prioritized [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Certain patients may also benefit from pharmacologic interventions, including dexmedetomidine [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Special attention is warranted for older adults with a positive CAM-ICU assessment, as they are at an increased risk for PMV and related complications.\u003c/p\u003e\u003cdiv id=\"Sec17\" class=\"Section2\"\u003e\u003ch2\u003eLIMITATIONS\u003c/h2\u003e\u003cp\u003eThis study has several limitations. First, as a retrospective, single-center analysis, it may be subject to selection biases that could not be fully addressed through statistical adjustments. Second, our cohort was confined to a single high-volume tertiary center, which may limit the generalizability of the findings to other practice settings. Third, CAM-ICU performance can be reduced in deeply sedated or hypoactive patients, potentially leading to under-detection; moreover, delirium severity, duration, and motor subtype were not captured and could modify risk estimates. Fourth, we did not assess patient-centered outcomes such as cognitive function, physical disability, or quality of life, which are increasingly emphasized in delirium research. Fifth, the overall mortality rate was low and the follow-up period may have been insufficient to detect modest long-term differences in survival. Finally, subgroup results\u0026mdash;particularly for patients aged\u0026thinsp;\u0026ge;\u0026thinsp;80 years\u0026mdash;should be interpreted with caution given small sample sizes, limited precision of age-interaction estimates, and the attendant risk of type II error.\u003c/p\u003e\u003c/div\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eA positive CAM-ICU assessment in the early postoperative period was associated with an increased risk of prolonged mechanical ventilation, reintubation, ICU readmission, and extended ICU stays among patients undergoing major cardiac surgery. Predicted ventilator duration was generally longer with a positive CAM-ICU assessment across most age groups, with attenuation in the very elderly. Routine CAM-ICU screening may help identify patients at risk of prolonged ventilation and enable timely, targeted interventions to improve postoperative respiratory recovery.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eCAM-ICU: Confusion Assessment Method for the Intensive Care Unit\u003c/p\u003e\n\u003cp\u003ePMV: Prolonged mechanical ventilation\u003c/p\u003e\n\u003cp\u003eICU: Intensive care unit\u003c/p\u003e\n\u003cp\u003ePEEP: Positive end-expiratory pressure\u003c/p\u003e\n\u003cp\u003eFiO\u003csub\u003e2\u003c/sub\u003e: Fraction of inspired oxygen\u003c/p\u003e\n\u003cp\u003eRR: Respiratory rate\u003c/p\u003e\n\u003cp\u003ePS: Pressure support\u003c/p\u003e\n\u003cp\u003eIPTW: Inverse-probability-of-treatment weighting\u003c/p\u003e\n\u003cp\u003eSMD: Standardized mean differences\u003c/p\u003e\n\u003cp\u003eeGFR: Estimated glomerular filtration rate\u003c/p\u003e\n\u003cp\u003eOR: Odds ratio\u003c/p\u003e\n\u003cp\u003eHR: Hazard ratio\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contribution\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eJYK was responsible for the methodology, data curation, formal analysis, visualization, and drafting the original manuscript. YAK contributed to data curation and the drafting of the original manuscript. PJK supervised the study, managed the project, and critically revised the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThere are no funding sources to declare.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets generated and/or analyzed during the current study are available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was conducted in accordance with the principles of the Declaration of Helsinki. The study protocol was approved by the Institutional Review Board of Asan Medical Center (Study no: 2025-0623; Date of approval: May 22, 2025). The requirement for informed consent was waived due to the observational nature of the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eSalluh JI, Wang H, Schneider EB, Nagaraja N, Yenokyan G, Damluji A, Serafim RB, Stevens RD: \u003cstrong\u003eOutcome of delirium in critically ill patients: systematic review and meta-analysis\u003c/strong\u003e. \u003cem\u003eBMJ \u003c/em\u003e2015, \u003cstrong\u003e350\u003c/strong\u003e:h2538.\u003c/li\u003e\n\u003cli\u003eChen H, Mo L, Hu H, Ou Y, Luo J: \u003cstrong\u003eRisk factors of postoperative delirium after cardiac surgery: a meta-analysis\u003c/strong\u003e. \u003cem\u003eJ Cardiothorac Surg \u003c/em\u003e2021, 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Confusion Assessment Method for the Intensive Care Unit (CAM-ICU)\u003c/strong\u003e. \u003cem\u003eCrit Care Med \u003c/em\u003e2001, \u003cstrong\u003e29\u003c/strong\u003e(7):1370-1379.\u003c/li\u003e\n\u003cli\u003eTrouillet JL, Combes A, Vaissier E, Luyt CE, Ouattara A, Pavie A, Chastre J: \u003cstrong\u003eProlonged mechanical ventilation after cardiac surgery: outcome and predictors\u003c/strong\u003e. \u003cem\u003eJ Thorac Cardiovasc Surg \u003c/em\u003e2009, \u003cstrong\u003e138\u003c/strong\u003e(4):948-953.\u003c/li\u003e\n\u003cli\u003eLaPar DJ, Gillen JR, Crosby IK, Sawyer RG, Lau CL, Kron IL, Ailawadi G: \u003cstrong\u003ePredictors of operative mortality in cardiac surgical patients with prolonged intensive care unit duration\u003c/strong\u003e. \u003cem\u003eJ Am Coll Surg \u003c/em\u003e2013, \u003cstrong\u003e216\u003c/strong\u003e(6):1116-1123.\u003c/li\u003e\n\u003cli\u003eJacobs JP, Shahian DM, Badhwar V, Thibault DP, Thourani VH, Rankin JS, Kurlansky PA, Bowdish ME, Cleveland JC, Jr., Furnary AP\u003cem\u003e et al\u003c/em\u003e: \u003cstrong\u003eThe Society of Thoracic Surgeons 2021 Adult Cardiac Surgery Risk Models for Multiple Valve Operations\u003c/strong\u003e. \u003cem\u003eAnn Thorac Surg \u003c/em\u003e2022, \u003cstrong\u003e113\u003c/strong\u003e(2):511-518.\u003c/li\u003e\n\u003cli\u003eMichaud L, Dureau P, Kerleroux B, Charfeddine A, Regan M, Constantin JM, Leprince P, Bougle A: \u003cstrong\u003eDevelopment and Validation of a Predictive Score for Prolonged Mechanical Ventilation After Cardiac Surgery\u003c/strong\u003e. \u003cem\u003eJ Cardiothorac Vasc Anesth \u003c/em\u003e2022, \u003cstrong\u003e36\u003c/strong\u003e(3):825-832.\u003c/li\u003e\n\u003cli\u003eJeon K: \u003cstrong\u003eImpact of delirium on weaning from mechanical ventilation in medical patients - Reply\u003c/strong\u003e. \u003cem\u003eRespirology \u003c/em\u003e2016, \u003cstrong\u003e21\u003c/strong\u003e(5):971.\u003c/li\u003e\n\u003cli\u003eDupuis S, Brindamour D, Karzon S, Frenette AJ, Charbonney E, Perreault MM, Bellemare P, Burry L, Williamson DR: \u003cstrong\u003eA systematic review of interventions to facilitate extubation in patients difficult-to-wean due to delirium, agitation, or anxiety and a meta-analysis of the effect of dexmedetomidine\u003c/strong\u003e. \u003cem\u003eCan J Anaesth \u003c/em\u003e2019, \u003cstrong\u003e66\u003c/strong\u003e(3):318-327.\u003c/li\u003e\n\u003cli\u003eStuart EA: \u003cstrong\u003eMatching methods for causal inference: A review and a look forward\u003c/strong\u003e. \u003cem\u003eStat Sci \u003c/em\u003e2010, \u003cstrong\u003e25\u003c/strong\u003e(1):1-21.\u003c/li\u003e\n\u003cli\u003eBoles JM, Bion J, Connors A, Herridge M, Marsh B, Melot C, Pearl R, Silverman H, Stanchina M, Vieillard-Baron A\u003cem\u003e et al\u003c/em\u003e: \u003cstrong\u003eWeaning from mechanical ventilation\u003c/strong\u003e. \u003cem\u003eEur Respir J \u003c/em\u003e2007, \u003cstrong\u003e29\u003c/strong\u003e(5):1033-1056.\u003c/li\u003e\n\u003cli\u003eShehabi Y, Chan L, Kadiman S, Alias A, Ismail WN, Tan MA, Khoo TM, Ali SB, Saman MA, Shaltut A\u003cem\u003e et al\u003c/em\u003e: \u003cstrong\u003eSedation depth and long-term mortality in mechanically ventilated critically ill adults: a prospective longitudinal multicentre cohort study\u003c/strong\u003e. \u003cem\u003eIntensive Care Med \u003c/em\u003e2013, \u003cstrong\u003e39\u003c/strong\u003e(5):910-918.\u003c/li\u003e\n\u003cli\u003eBalzer F, Weiss B, Kumpf O, Treskatsch S, Spies C, Wernecke KD, Krannich A, Kastrup M: \u003cstrong\u003eEarly deep sedation is associated with decreased in-hospital and two-year follow-up survival\u003c/strong\u003e. \u003cem\u003eCrit Care \u003c/em\u003e2015, \u003cstrong\u003e19\u003c/strong\u003e(1):197.\u003c/li\u003e\n\u003cli\u003eReddy SL, Grayson AD, Griffiths EM, Pullan DM, Rashid A: \u003cstrong\u003eLogistic risk model for prolonged ventilation after adult cardiac surgery\u003c/strong\u003e. \u003cem\u003eAnn Thorac Surg \u003c/em\u003e2007, \u003cstrong\u003e84\u003c/strong\u003e(2):528-536.\u003c/li\u003e\n\u003cli\u003eRajakaruna C, Rogers CA, Angelini GD, Ascione R: \u003cstrong\u003eRisk factors for and economic implications of prolonged ventilation after cardiac surgery\u003c/strong\u003e. \u003cem\u003eJ Thorac Cardiovasc Surg \u003c/em\u003e2005, \u003cstrong\u003e130\u003c/strong\u003e(5):1270-1277.\u003c/li\u003e\n\u003cli\u003eHughes CG, Hayhurst CJ, Pandharipande PP, Shotwell MS, Feng X, Wilson JE, Brummel NE, Girard TD, Jackson JC, Ely EW\u003cem\u003e et al\u003c/em\u003e: \u003cstrong\u003eAssociation of Delirium during Critical Illness With Mortality: Multicenter Prospective Cohort Study\u003c/strong\u003e. \u003cem\u003eAnesth Analg \u003c/em\u003e2021, \u003cstrong\u003e133\u003c/strong\u003e(5):1152-1161.\u003c/li\u003e\n\u003cli\u003eDuprey MS, van den Boogaard M, van der Hoeven JG, Pickkers P, Briesacher BA, Saczynski JS, Griffith JL, Devlin JW: \u003cstrong\u003eAssociation between incident delirium and 28- and 90-day mortality in critically ill adults: a secondary analysis\u003c/strong\u003e. \u003cem\u003eCrit Care \u003c/em\u003e2020, \u003cstrong\u003e24\u003c/strong\u003e(1):161.\u003c/li\u003e\n\u003cli\u003eReznik ME, Slooter AJC: \u003cstrong\u003eDelirium Management in the ICU\u003c/strong\u003e. \u003cem\u003eCurr Treat Options Neurol \u003c/em\u003e2019, \u003cstrong\u003e21\u003c/strong\u003e(11):59.\u003c/li\u003e\n\u003cli\u003eDuan X, Coburn M, Rossaint R, Sanders RD, Waesberghe JV, Kowark A: \u003cstrong\u003eEfficacy of perioperative dexmedetomidine on postoperative delirium: systematic review and meta-analysis with trial sequential analysis of randomised controlled trials\u003c/strong\u003e. \u003cem\u003eBr J Anaesth \u003c/em\u003e2018, \u003cstrong\u003e121\u003c/strong\u003e(2):384-397.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1.\u0026nbsp;\u003c/strong\u003eBaseline characteristics and operative profiles according to the CAM-ICU status in the unadjusted and IPTW-adjusted cohorts\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"841\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOriginal\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 103px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 198px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIPTW-adjusted\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariables\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCAM-ICU (-)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(N=1156)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 103px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCAM-ICU (+)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(N=281)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 52px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSMD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCAM-ICU (-)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(N=1156)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCAM-ICU (+)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(N=281)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 57px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSMD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003eAge (years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e59.6 \u0026plusmn; 12.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e66.3 \u0026plusmn; 11.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e55.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e61.1 \u0026plusmn; 12.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e60.6 \u0026plusmn; 12.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.718\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e3.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e429 (37.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e121 (43.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.076\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e12.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e439 (38.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e104 (37.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.820\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e2.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003eBMI (kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e24.2 \u0026plusmn; 3.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e24.0 \u0026plusmn; 4.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.494\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e4.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e24.1 \u0026plusmn; 3.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e24.2 \u0026plusmn; 4.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.785\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e2.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003eHypertension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e627 (54.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e180 (64.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.004\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e20.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e645 (55.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e163 (57.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.630\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e4.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003eDiabetes mellitus\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e282 (24.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e90 (32.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.011\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e17.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e302 (26.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e77 (27.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.755\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e2.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003eCerebrovascular disease\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e109 (9.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e39 (13.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.036\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e13.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e124 (10.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e31 (11.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.881\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e1.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003eCOPD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e52 (4.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e30 (10.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e43.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e70 (6.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e15 (5.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.614\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e3.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003eeGFR\u0026nbsp;(mL/min/1.73\u0026nbsp;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 103px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 52px;\"\u003e\n \u003cp\u003e43.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.883\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e3.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026lt;30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e47 (4.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e26 (9.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e59 (5.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e13 (4.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;30\u0026ndash;60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e137 (11.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e71 (25.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e167 (14.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e38 (13.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026gt;60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e972 (84.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e184 (65.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e930 (80.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e230 (81.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003eHistory of cardiac surgery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e164 (14.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e67 (23.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e24.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e192 (16.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e46 (16.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.910\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003eHemoglobin (g/dL)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e12.8 \u0026plusmn; 1.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 103px;\"\u003e\n \u003cp\u003e11.9 \u0026plusmn; 2.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e44.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e12.6 \u0026plusmn; 2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e12.7 \u0026plusmn; 2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.487\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e6.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003ePMV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e8 (0.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e9 (3.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e18.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e17 (1.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e4 (1.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.815\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e1.4%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003eHistory of ICU admission\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e55 (4.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e42 (14.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e34.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e78 (6.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e18 (6.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.749\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e2.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003ePreoperative ECMO support\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e8 (0.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e11 (3.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e21.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e17 (1.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e4 (1.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.890\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e\u003cu\u003eOperative profile\u003c/u\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 103px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Operation type\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 103px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e28.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.979\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e7.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u003cstrong\u003e\u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/strong\u003eValve\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e624 (54.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e129 (45.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e602 (52.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e143 (50.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; CABG\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e184 (15.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e48 (17.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e186 (16.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e53 (18.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; Aorta\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e95 (8.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e40 (14.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e117 (10.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e29 (10.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; Valve + CABG\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e39 (3.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e16 (5.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e43 (3.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e10 (3.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; Valve + Aorta\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e88 (7.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e23 (8.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e92 (8.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e21 (7.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; CABG + Aorta\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e3 (0.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e3 (1.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e4 (0.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e1 (0.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; Others\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e123 (10.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e22 (7.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e113 (9.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e25 (8.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Operative time, hours\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e3.8 \u0026plusmn; 1.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e4.7 \u0026plusmn; 1.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e59.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e4.0 \u0026plusmn; 1.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e4.0 \u0026plusmn; 1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.562\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e4.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eMICS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e598 (51.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e96 (34.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e36.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e551 (47.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e132 (46.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.862\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e1.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Emergent operation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e110 (9.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 103px;\"\u003e\n \u003cp\u003e49 (17.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e23.4%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e134 (11.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e28 (9.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.459\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e5.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003eICU stay (days)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e1 (1\u0026ndash;2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 103px;\"\u003e\n \u003cp\u003e3 (2\u0026ndash;8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e54.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e1 (1\u0026ndash;2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e2 (1\u0026ndash;4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e27.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 187px;\"\u003e\n \u003cp\u003eHospital stay (days)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e8 (7\u0026ndash;12)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 103px;\"\u003e\n \u003cp\u003e14 (9\u0026ndash;36)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.023\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e9.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e9 (7\u0026ndash;13)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e10 (8\u0026ndash;21)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.302\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e9.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eValues are presented as n (%), mean \u0026plusmn; standard deviation, or median (interquartile range: Q1\u0026ndash;Q3), unless otherwise specified. IPTW, Inverse-probability-of-treatment weighting; SMD, Standardized mean difference; BMI, Body mass index; COPD, Chronic obstructive pulmonary disease; eGFR, Estimated glomerular filtration rate; PMV, Preoperative mechanical ventilation; ICU, Intensive care unit; ECMO, Extracorporeal membrane oxygenation; CABG, Coronary artery bypass graft surgery; MICS, Minimally invasive cardiac surgery\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2.\u0026nbsp;\u003c/strong\u003eEarly and overall clinical outcomes according to the CAM-ICU status in the unadjusted and IPTW-adjusted cohorts\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"841\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 217px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 195px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOriginal\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIPTW-adjusted\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 217px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" style=\"width: 195px;\"\u003e\n \u003cp\u003eNo. of events (rate)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 217px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOutcomes\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCAM-ICU (-)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(N=1156)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 101px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCAM-ICU (+)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(N=281)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003eOR or HR\u003c/p\u003e\n \u003cp\u003e(95% CI)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eOR or HR\u003c/p\u003e\n \u003cp\u003e(95% CI)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003ep-value\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 217px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eEarly Outcomes\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 101px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 217px;\"\u003e\n \u003cp\u003eProlonged ventilation \u0026gt; 24 hours\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e62 (5.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 101px;\"\u003e\n \u003cp\u003e105 (37.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003e10.52 (7.43\u0026ndash;15.04)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e3.60 (2.53\u0026ndash;5.10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 217px;\"\u003e\n \u003cp\u003eEarly death\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e9 (0.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 101px;\"\u003e\n \u003cp\u003e9 (3.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003e4.21 (1.67\u0026ndash;10.60)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e0.003\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e1.13 (0.37\u0026ndash;2.86)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e0.805\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 217px;\"\u003e\n \u003cp\u003eReintubation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e14 (1.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 101px;\"\u003e\n \u003cp\u003e23 (8.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003e7.27 (3.73\u0026ndash;14.66)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e3.37 (1.52\u0026ndash;7.31)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 217px;\"\u003e\n \u003cp\u003eICU readmission\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e21 (1.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 101px;\"\u003e\n \u003cp\u003e24 (8.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003e5.05 (2.77\u0026ndash;9.28)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e2.53 (1.22\u0026ndash;5.03)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e0.010\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 217px;\"\u003e\n \u003cp\u003eProlonged ICU stay after extubation (\u0026gt;48 hr)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e198 (17.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 101px;\"\u003e\n \u003cp\u003e129 (45.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003e4.10 (3.10\u0026ndash;5.44)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e2.95 (2.19\u0026ndash;3.96)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 217px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eOverall Outcomes\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 101px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 217px;\"\u003e\n \u003cp\u003eAll-cause death\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e12 (1.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 101px;\"\u003e\n \u003cp\u003e20 (7.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 135px;\"\u003e\n \u003cp\u003e4.11 (1.63\u0026ndash;10.36)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e0.003\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e1.77 (0.79\u0026ndash;3.95)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 94px;\"\u003e\n \u003cp\u003e0.164\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eValues are presented as n (%). Odds ratios and hazard ratios are presented for early outcomes and overall outcomes, respectively. OR, Odds ratio; HR, Hazard ratio; CI, Confidence interval; IPTW, Inverse-probability-of-treatment weighting; ICU, Intensive care unit\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3.\u0026nbsp;\u003c/strong\u003eUnivariable logistic regression for predictors of prolonged mechanical ventilation after major cardiac surgery\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"595\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariables\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 246px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eAge\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e1.03 (1.01\u0026ndash;1.04)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eFemale sex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e1.22 (0.88\u0026ndash;1.69)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.231\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eBMI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e1.02 (0.97\u0026ndash;1.06)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.418\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eHypertension\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e1.33 (0.96\u0026ndash;1.86)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.091\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eDiabetes mellitus\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e1.38 (0.97\u0026ndash;1.96)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.067\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eCerebrovascular disease\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e1.29 (0.77\u0026ndash;2.08)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.305\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eCOPD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e2.28 (1.28\u0026ndash;3.87)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.003\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eeGFR\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026lt;30 mL/min/1.73\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e5.29 (3.07\u0026ndash;8.91)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 30\u0026ndash;60 mL/min/1.73\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e2.98 (2.01\u0026ndash;4.38)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026gt;60 mL/min/1.73\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003eReference\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eHistory of cardiac surgery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e4.10 (2.88\u0026ndash;5.82)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eHemoglobin\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e0.73 (0.67\u0026ndash;0.79)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003ePreoperative mechanical ventilation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e19.59 (7.16\u0026ndash;62.24)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eHistory of ICU admission\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e8.21 (5.27\u0026ndash;12.76)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003ePreoperative ECMO support\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e17.78 (6.92\u0026ndash;51.24)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eCAM-ICU\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e10.53 (7.43\u0026ndash;15.04)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e\u003cu\u003eOperative profile\u003c/u\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; Operation type\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003cstrong\u003e\u0026nbsp; \u0026nbsp;\u003c/strong\u003eValve\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003eReference\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; CABG\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e0.70 (0.39\u0026ndash;1.20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.215\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eAorta\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e3.18 (2.00\u0026ndash;5.01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eValve + CABG\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e0.74 (0.22\u0026ndash;1.88)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.576\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eValve + Aorta\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e2.21 (1.27\u0026ndash;3.71)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.004\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; CABG + Aorta\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e4.72 (0.65\u0026ndash;24.67)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.757\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Others\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e1.34 (0.75\u0026ndash;2.28)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.296\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eOperative time\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e1.89 (1.70\u0026ndash;2.10)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eMICS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e1.74 (0.89-3.39)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 76px;\"\u003e\n \u003cp\u003e0.105\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 274px;\"\u003e\n \u003cp\u003eEmergent operation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 246px;\"\u003e\n \u003cp\u003e5.93 (4.05\u0026ndash;8.65)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 76px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eOR, Odds ratio; CI, Confidence interval; BMI, Body mass index; COPD, Chronic obstructive pulmonary disease; eGFR, Estimated glomerular\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003efiltration rate; ICU, Intensive care unit; ECMO, Extracorporeal membrane oxygenation; CABG, Coronary artery bypass graft surgery; MICS, Minimally invasive cardiac surgery.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4.\u0026nbsp;\u003c/strong\u003eMultivariable logistic regression for predictors of prolonged mechanical ventilation after major cardiac surgery\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"536\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 243px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariables\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 151px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOR (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 142px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 243px;\"\u003e\n \u003cp\u003eBMI\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e1.07 (1.01\u0026ndash;1.12)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 142px;\"\u003e\n \u003cp\u003e0.015\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 243px;\"\u003e\n \u003cp\u003eeGFR\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 142px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 243px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026lt;30 mL/min/1.73\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e2.63 (1.29\u0026ndash;5.27)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 142px;\"\u003e\n \u003cp\u003e0.007\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 243px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 30\u0026ndash;60 mL/min/1.73\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e1.57 (0.94\u0026ndash;2.58)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 142px;\"\u003e\n \u003cp\u003e0.080\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 243px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026gt;60 mL/min/1.73\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003eReference\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 142px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 243px;\"\u003e\n \u003cp\u003eHistory of cardiac surgery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e2.27 (1.43\u0026ndash;3.57)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 142px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 243px;\"\u003e\n \u003cp\u003eHemoglobin\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e0.87 (0.78\u0026ndash;0.96)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 142px;\"\u003e\n \u003cp\u003e0.007\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 243px;\"\u003e\n \u003cp\u003ePreoperative mechanical ventilation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e6.70 (2.02\u0026ndash;24.94)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 142px;\"\u003e\n \u003cp\u003e0.003\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 243px;\"\u003e\n \u003cp\u003eCAM-ICU\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e7.35 (4.86\u0026ndash;11.22)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 142px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 243px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003e\u003cu\u003eOperative profile\u003c/u\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 142px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 243px;\"\u003e\n \u003cp\u003eAortic surgery\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e1.85 (1.14\u0026ndash;2.96)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 142px;\"\u003e\n \u003cp\u003e0.011\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 243px;\"\u003e\n \u003cp\u003eOperative time\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e1.55 (1.37\u0026ndash;1.75)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 142px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 243px;\"\u003e\n \u003cp\u003eEmergent operation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 151px;\"\u003e\n \u003cp\u003e3.40 (2.02\u0026ndash;5.70)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 142px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eCandidate covariates were initially screened with univariable analyses (\u003cstrong\u003eTable 3\u003c/strong\u003e). Clinically significant covariates with a p value lower than 0.10 in univariable models were used in the multivariable model. Covariates that remained in the multivariable model using the backward elimination technique were retained in the multivariable model.\u003c/p\u003e\n\u003cp\u003eOR, Odds ratio; CI, Confidence interval; BMI, Body mass index; eGFR, Estimated glomerular\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003efiltration rate; CAM-ICU, Confusion assessment method for the intensive care unit.\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":"european-journal-of-medical-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ejmr","sideBox":"Learn more about [European Journal of Medical Research](http://eurjmedres.biomedcentral.com)","snPcode":"40001","submissionUrl":"https://submission.nature.com/new-submission/40001/3","title":"European Journal of Medical Research","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"delirium, CAM-ICU, prolonged mechanical ventilation, cardiac surgery","lastPublishedDoi":"10.21203/rs.3.rs-7745930/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7745930/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cb\u003eBackground\u003c/b\u003e\u003c/p\u003e\u003cp\u003eDelirium is common after cardiac surgery and has been associated with adverse outcomes in critically ill patients. The Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) is a validated tool for detecting delirium; however, few studies have explored its association with prolonged mechanical ventilation (PMV) following major cardiac surgery. This study aimed to investigate whether a positive CAM-ICU assessment is associated with PMV and other postoperative outcomes in this population.\u003c/p\u003e\u003cp\u003e\u003cb\u003eMethods\u003c/b\u003e\u003c/p\u003e\u003cp\u003eWe conducted a retrospective cohort study of 1,437 adult patients who underwent cardiac surgery in 2022. Delirium was assessed daily using the CAM-ICU during the early postoperative period. PMV was defined as ventilation lasting more than 24 hours after surgery. Clinical outcomes were analyzed using logistic regression and time-dependent Cox regression, with adjustments made using inverse probability of treatment weighting (IPTW).\u003c/p\u003e\u003cp\u003e\u003cb\u003eResults\u003c/b\u003e\u003c/p\u003e\u003cp\u003eAmong 1,437 patients, 281 (19.6%) were assessed as CAM-ICU positive in the early postoperative period. After IPTW adjustment, a positive CAM-ICU assessment was significantly associated with increased risk of PMV (odds ratio [OR] 3.60; 95% CI, 2.53\u0026ndash;5.10; p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), reintubation (OR 3.37; 95% CI, 1.52\u0026ndash;7.31; p\u0026thinsp;=\u0026thinsp;0.002), intensive care unit (ICU) readmission (OR 2.53; 95% CI, 1.22\u0026ndash;5.03; p\u0026thinsp;=\u0026thinsp;0.010), and prolonged ICU stay after extubation (OR 2.95; 95% CI, 2.19\u0026ndash;3.96; p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Neither early death nor all-cause mortality differed significantly between groups after IPTW adjustment. Age-related analyses indicated that predicted ventilator duration was generally longer with a positive CAM-ICU assessment across most age groups, with attenuation of this difference in the very elderly (\u0026ge;\u0026thinsp;80 years).\u003c/p\u003e\u003cp\u003e\u003cb\u003eConclusion\u003c/b\u003e\u003c/p\u003e\u003cp\u003eAn early postoperative positive CAM-ICU assessment was associated with higher risks of PMV, reintubation, ICU readmission, and prolonged ICU stay after major cardiac surgery. Routine CAM-ICU screening may help identify patients at risk of prolonged ventilation and enable timely, targeted interventions to improve postoperative respiratory recovery.\u003c/p\u003e","manuscriptTitle":"Association Between the Confusion Assessment Method for the Intensive Care Unit (CAM- ICU) and Prolonged Mechanical Ventilation Following Major Cardiac Surgery","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-27 14:36:59","doi":"10.21203/rs.3.rs-7745930/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-10-25T18:50:17+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-25T05:49:19+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-19T14:32:38+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"88811978658550714566416165458520225735","date":"2025-10-19T13:31:11+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"210356279580220315381474082066747896003","date":"2025-10-16T22:04:02+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-15T20:42:05+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"144760971613448631305715322413087832353","date":"2025-10-15T00:55:08+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-10-13T19:07:58+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-06T17:31:24+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-06T14:42:55+00:00","index":"","fulltext":""},{"type":"submitted","content":"European Journal of Medical Research","date":"2025-09-30T01:08:02+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"european-journal-of-medical-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"ejmr","sideBox":"Learn more about [European Journal of Medical Research](http://eurjmedres.biomedcentral.com)","snPcode":"40001","submissionUrl":"https://submission.nature.com/new-submission/40001/3","title":"European Journal of Medical Research","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"a9c3abc7-a366-4259-a94f-c0f3caa3f9d3","owner":[],"postedDate":"October 27th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2026-01-26T16:04:31+00:00","versionOfRecord":{"articleIdentity":"rs-7745930","link":"https://doi.org/10.1186/s40001-025-03757-z","journal":{"identity":"european-journal-of-medical-research","isVorOnly":false,"title":"European Journal of Medical Research"},"publishedOn":"2026-01-21 15:58:00","publishedOnDateReadable":"January 21st, 2026"},"versionCreatedAt":"2025-10-27 14:36:59","video":"","vorDoi":"10.1186/s40001-025-03757-z","vorDoiUrl":"https://doi.org/10.1186/s40001-025-03757-z","workflowStages":[]},"version":"v1","identity":"rs-7745930","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7745930","identity":"rs-7745930","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}