Difficult and Complex Separation from Cardiopulmonary Bypass in High-Risk Cardiac Surgical Patients: A Multicenter Study

ObjectivesTo determine the impact of the pharmacologic and mechanical support required during separation from cardiopulmonary bypass (CPB) on survival after cardiac surgery. The authors hypothesized that difficulty with separation from CPB was associated independently with life-threatening complications and survival after cardiac surgery.DesignProspective study.SettingNineteen tertiary care hospitals involved in the Blood Conservation Using Antifibrinolytics in a Randomized Controlled Trial (BART).ParticipantsHigh-risk cardiac surgical patients.InterventionSeparation from CPB was stratified as easy when no support or only one vasoactive agent or inotrope was required, difficult or pharmacologically assisted when the 2 drug types were used, and complex when the first weaning process failed or the patient required mechanical devices to be weaned from CPB. These definitions were based on a retrospective analysis of 6,120 consecutive cardiac surgical patients who underwent cardiac surgery in a single center.Measurements and Main ResultsBackward logistic regression was performed to determine predictors of life-threatening complications and mortality. There were 2,331 patients with a mean age of 66 ± 11 years, and 71.8% were men. There were 1,158 (49.7%), 835 (35.8%) and 338 (14.5%) patients in the easy, difficult, and complex categories, respectively. One hundred eight patients died (4.6%), 84 (77.8%) of whom had difficulty in weaning from CPB. Complex separation from CPB was found to be an independent predictor of mortality (odds ratio 3.091, 95% confidence interval 1.706-5.601).ConclusionsDifficulty in the process of separation from CPB is an independent predictor of mortality and adverse outcome after cardiac surgery (Current Controlled Trials, indentifier ISRCTN15166455).