Effect of smoking on short-term outcome of patients undergoing coronary artery bypass surgery

Data on the effect of smoking on short-term outcome in patients undergoing coronary artery bypass graft (CABG) surgery are limited. We sought to assess the morbidity and in-hospital mortality of smokers and former smokers compared with nonsmokers undergoing CABG.

This is a retrospective review of prospectively collected departmental data base. In all, 2,587 consecutive patients underwent isolated CABG between February 2000 and June 2007. Of these, 475 patients were current smokers, 1,364 were former smokers of more than 4 weeks, and 748 were nonsmokers.

Current smokers had higher rates of postoperative pulmonary complications than former smokers and nonsmokers (30.1% versus 23.3% versus 19.9%, p < 0.001). Blood transfusion requirement was lower for current smokers group than for the other two groups (34.9% versus 37.5% versus 44.1%, p = 0.02). Adjusted odd ratios (OR) for early clinical outcomes showed that current smokers had 59% higher risk of developing pulmonary complications (OR 1.59) than nonsmokers, with former smokers showing an intermediate pattern (OR 1.17). Current smokers had 36% lower risk of postoperative blood transfusion than nonsmokers (OR 0.64), with former smokers showing an intermediate pattern (OR 0.94). Rates of other postoperative complications, intensive care unit readmission, postoperative length of stay, and mortality did not differ among the three groups.

Smoking is associated with significant pulmonary complications after CABG. In-hospital mortality is not influenced by smoking. Smokers should be encouraged to quit before undergoing CABG, and a period of 1 month may be beneficial, given that former smokers in our study seem to have better prognosis than current smokers.