Insulin use and clinical outcomes in patients undergoing coronary artery bypass graft surgery

Abstract Objective: To describe insulin use and postoperative glucose control in patients undergoing coronary artery bypass graft (CABG) surgery. Methods: We examined 2,390 patients with and without diabetes enrolled in the Contemporary Analysis of Perioperative Cardiovascular Surgical Care (CAPS-Care) Study who underwent CABG surgery (01/2004 - 06/2005) to describe postoperative insulin use, variation in insulin use across different hospitals, and associated in-hospital complications and clinical outcomes. Logistic regression was used to assess the adjusted relationship between insulin use and clinical outcomes. Results: Overall, insulin was used in 82% (n=1,959) of patients, including 95% (n=1,203) with diabetes (n=1,258) and 67% (n=756) without diabetes (n=1,132). Continuous insulin was used in 35.5% of patients in the operating room and in 56% in the intensive care unit. Continuous insulin use varied significantly among centers from 8-100% in patients with diabetes. When compared with all patients not receiving insulin, insulin use in patients without diabetes was associated with a higher rate of death or major complication (adjusted odds ratio [OR]=1.54; 95% confidence interval [CI] 1.15-2.04; P=0.003). In patients with diabetes, insulin use was not associated with a higher risk of adverse outcomes (adjusted OR=1.01; 95% CI 0.52-1.98; P=0.98). Conclusion: The postoperative use of insulin is high among CABG patients in the United States of America. Insulin use in patients without diabetes was associated with worse clinical outcomes compared to patients (both with and without diabetes) who did not receive insulin. Further investigation is needed to determine the optimal use of postoperative insulin after CABG.

Clopidogrel use after myocardial revascularization: prevalence, predictors, and one-year survival rate

Abstract Introduction: Antiplatelet therapy after coronary artery bypass graft (CABG) has been used. Little is known about the predictors and efficacy of clopidogrel in this scenario. Objective: Identify predictors of clopidogrel following CABG. Methods: We evaluated 5404 patients who underwent CABG between 2000 and 2009 at Duke University Medical Center. We excluded patients undergoing concomitant valve surgery, those who had postoperative bleeding or death before discharge. Postoperative clopidogrel was left to the discretion of the attending physician. Adjusted risk for 1-year mortality was compared between patients receiving and not receiving clopidogrel during hospitalization after undergoing CABG. Results: At hospital discharge, 931 (17.2%) patients were receiving clopidogrel. Comparing patients not receiving clopidogrel at discharge, users had more comorbidities, including hyperlipidemia, hypertension, heart failure, peripheral arterial disease and cerebrovascular disease. Patients who received aspirin during hospitalization were less likely to receive clopidogrel at discharge (P≤0.0001). Clopidogrel was associated with similar 1-year mortality compared with those who did not use clopidogrel (4.4% vs. 4.5%, P=0.72). There was, however, an interaction between the use of cardiopulmonary bypass and clopidogrel, with lower 1-year mortality in patients undergoing off-pump CABG who received clopidogrel, but not those undergoing conventional CABG (2.6% vs 5.6%, P Interaction = 0.032). Conclusion: Clopidogrel was used in nearly one-fifth of patients after CABG. Its use was not associated with lower mortality after 1 year in general, but lower mortality rate in those undergoing off-pump CABG. Randomized clinical trials are needed to determine the benefit of routine use of clopidogrel in CABG.