Impact of off-pump coronary artery bypass graft surgery on postoperative pulmonary complications in patients with chronic lung disease

Abstract

Background: Off-pump coronary artery bypass graft surgery (OPCAB) has proven to be beneficial in many high-risk subgroups. This study aims to determine whether OPCAB lowers the incidence of pulmonary complications among patients with chronic lung disease (CLD) when compared with on-pump coronary artery bypass graft surgery (ONCAB).

Methods: From 2002 to 2007, 7,060 patients underwent isolated coronary artery bypass graft surgery in an academic center. Patients were classified according to surgery type (ONCAB or OPCAB) and presence or absence of CLD. A propensity score was produced to estimate each patient's likelihood of being assigned to OPCAB on the basis of 39 preoperative risk factors. Multiple logistic regression models and adjusted odds ratios with 95% confidence intervals were used to evaluate the effect of surgery type, CLD, and their interaction on pulmonary-related complications and mortality.

Results: Among OPCAB patients, 15.3% (720 of 4,693) had CLD compared with 11.2% (264 of 2,367) for ONCAB. Off-pump coronary artery bypass graft surgery was performed in 73.2% of CLD patients compared with 66.5% in those without CLD (p<0.0001). Chronic lung disease was associated with a greater incidence of prolonged ventilation, reintubation, pneumonia, intensive care unit hours, and non-home discharge. After propensity score adjustment, OPCAB was associated with a significantly reduced incidence of prolonged ventilation, pneumonia, intensive care unit stay, and mortality. No significant interactions existed between surgery type and CLD status, suggesting that OPCAB was equally beneficial to patients with and without CLD.

Conclusions: In this series, patients with CLD were more likely to undergo OPCAB. Patients with CLD are at significantly greater risk of pulmonary-related complications than patients without CLD. Off-pump coronary artery bypass graft surgery reduced the incidence of pulmonary complications and mortality in all patients. Importantly, this benefit was seen similarly for patients with and without CLD.