Postoperative Inotrope and Vasopressor Use Following CABG: Outcome Data from the CAPS-Care Study

Abstract

Limited clinical data exist to guide practice patterns and evidence-based use of inotropes and vasopressors following coronary artery bypass grafting (CABG). Contemporary Analysis of Perioperative Cardiovascular Surgical Care (CAPS-Care) collected detailed perioperative data from 2390 CABG patients between 2004 and 2005 at 55 U.S. hospitals. High-risk elective or urgent CABG patients were eligible for inclusion. We stratified participating hospitals into high, medium, and low tertiles of inotrope use. Hospital-level outcomes were compared before and after risk adjustment for baseline characteristics. Hospital-level risk-adjusted rates of any inotrope/vasopressor use varied from 100% to 35%. Hospitals in the highest tertile of use had more patients with mitral regurgitation compared to medium- or low-use hospitals (p < 0.001), more previous cardiovascular interventions (p = 0.002), longer cardiopulmonary bypass (p < 0.001), longer cross-clamp times (p < 0.001), and required more transfusions (p = 0.001). Despite these differences, unadjusted outcomes were similar between high-, medium-, and low-use hospitals for operative mortality (4.5% vs. 5.3% vs. 5.2%; p = 0.702), 30-day mortality (4.1% vs. 4.6% vs. 5.0%; p = 0.690), postoperative renal failure (7.2% vs. 9.2% vs. 6.6%; p = 0.142), atrial fibrillation (23.0% vs. 27.2% vs. 25.6%; p = 0.106), and acute limb ischemia (0.6% vs. 0.5% vs. 0.5%; p = 0.945). These similar outcomes persisted after risk adjustment: adjusted OR = 0.97 (95% CI [0.94, 1.00], p = 0.086) for operative mortality and adjusted OR = 1.00 (95% CI [0.96, 1.04], p = 0.974) for postoperative renal failure. While considerable variability is present among hospitals in inotrope use following CABG, observational comparison of outcomes did not distinguish a superior pattern; thus, randomized prospective data are needed to better guide clinical practice.