Predictors of inotropic support during weaning from cardiopulmonary bypass in coronary artery bypass grafting surgery

Early or prophylactic inotropic drug administration is occasionally required to facilitate separation from cardiopulmonary bypass (CPB) in cardiac surgery. However, it is not without untoward effects and should be conducted on the basis of rational criteria. The purpose of our study was to clarify variables associated with the requirement for inotropic support during separation from CPB and to testify whether pre-CPB left ventricular (LV) function, as evaluated by transesophageal echocardiography (TEE), is one of the significant variables. Clinical profile data and TEE findings were retrospectively analyzed for 91 patients who had received elective primary isolated coronary artery bypass grafting (CABG) surgery. Post-CPB inotropic drug administration initiated prior to aortic decannulation was considered inotropic support for terminating CPB. Stepwise multiple logistic regression analysis identified pre-CPB LV regional wall motion abnormalities (RWMA), NYHA class, age, and duration of CPB (in order of significance) as factors associated with inotropic support for discontinuing CPB. Pre-CPB LV end-diastolic area or fractional area change was not a significant variable in the multivariate model. Our result suggests that evaluation of pre-CPB LV RWMA is useful in predicting the need of inotropic intervention during separation from CPB in patients undergoing CABG surgery.