Cardiopulmonary Bypass Duration Is an Independent Predictor of Morbidity and Mortality After Cardiac Surgery

Objective

The aim of this study was to determine if there is a direct relationship between the duration of cardiopulmonary bypass (CPB time [CPBT]) and postoperative morbidity and mortality in patients undergoing cardiac surgery.

Design

Retrospective study.

Setting

Cardiac surgery unit, university hospital.

Participants

Five thousand six patients, New York Heart Association classes 1 through 4, who underwent cardiac surgery between January 2002 and March 2008.

Interventions

All patients were subjected to CPB.

Measurements and Main Results

The mean CPBT was 115 minutes (median 106). One hundred thirty-one patients (2.6%) died during the same hospitalization. The postoperative median blood loss was 600 mL. Reoperations for bleeding occurred in 193 patients (3.9%), and 1,001 patients received 3 or more units of red blood cells. There were 108 patients (2.2%) with neurologic sequelae, 391 patients (7.8%) with renal complications, 37 patients (0.7%) with abdominal complications, and 184 patients (3.7%) with respiratory complications. Seventy-two patients (1.4%) had an infective complication, and 80 patients (1.6%) had a postoperative multiorgan failure. The multivariate analysis confirmed the role of CPBT, considered in 30-minute increments, as an independent risk factor for postoperative death (odds ratio [OR] = 1.57, p < 0.0001), pulmonary (OR = 1.17, p < 0.0001), renal (OR 1.31, p < 0.0001), and neurologic complications (OR = 1.28, p < 0.0001), multiorgan failure (OR = 1.21, p < 0.0001), reoperation for bleeding (OR = 1.1, p = 0.0165), and multiple blood transfusions (OR = 1.58, p < 0.0001).

Conclusions

Prolonged CPB duration independently predicts postoperative morbidity and mortality after cardiac surgery.

Key Words: cardiac surgery, cardiopulmonary bypass, postoperative complications