Smoking and timing of cessation: impact on pulmonary complications after thoracotomy

The benefit of smoking cessation just prior to surgery in preventing postoperative pulmonary complications has not been proven. Some studies actually show a paradoxical increase in complications in those quitting smoking only a few weeks or days prior to surgery. We studied the effect of smoking and the timing of smoking cessation on postoperative pulmonary complications in patients undergoing thoracotomy.

Prospective study conducted in a tertiary care cancer center in 300 consecutive patients with primary lung cancer or metastatic cancer to the lung who were undergoing anatomical lung resection.

The groups studied were nonsmokers (21%), past quitters of > 2 months duration (62%), recent quitters of < 2 months duration (13%), and ongoing smokers (4%). Overall pulmonary complications occurred in 8%, 19%, 23%, and 23% of these groups, respectively, with a significant difference between nonsmokers and all smokers (p = 0.03) but no difference among the subgroups of smokers (p = 0.76). The risk of pneumonia was significantly lower in nonsmokers (3%) compared to all smokers (average, 11%; p < 0.05), with no difference detected among subgroups of smokers (p = 0.17). Comparing recent quitters and ongoing smokers, no differences in pulmonary complications or pneumonia were found (p = 0.67). Independent risk factors for pulmonary complications were a lower diffusing capacity of the lung for carbon monoxide (Dlco) [odds ratio [ OR] per 10% decrement, 1.41; 95% confidence interval [ CI], 1.17 to 1.70; p = 0.01) and primary lung cancer rather than metastatic disease (OR, 3.94; 95% CI, 1.34 to 11.59; p = 0.003). Among smokers, a lower Dlco percent predicted (OR per 10% decrement, 1.42; 95% CI, 1.16 to 1.75; p = 0.008) and a smoking history of > 60 pack-years (OR, 2.54; 95% CI, 1.28 to 5.04; p = 0.0008) were independently associated with overall pulmonary complications.

In patients undergoing thoracotomy for primary or secondary lung tumors, there is no evidence of a paradoxical increase in pulmonary complications among those who quit smoking within 2 months of undergoing surgery. Smoking cessation can safely be encouraged prior to surgery.