Level 1: Likely reliable evidence
A recently published systematic review evaluated smoking cessation interventions in nine randomized trials with 1,194 patients undergoing planned surgery (Br J Surg. 2009;96:451-461). Although an overall meta-analysis was reported, the data are more accurately summarized by two subgroups. In one subgroup, two high-quality trials evaluated intensive smoking cessation interventions with four to eight weekly counseling sessions and nicotine replacement therapy. Intensive smoking cessation interventions reduced the rate of postoperative complications from 46% to 19% in a pooled analysis (NNT 4). Reductions were seen in wound complications, prolonged hospital stay, unscheduled postoperative checkups, and events causing additional treatment or investigations. The other trials, which evaluated less intensive interventions, did not find a significant reduction in postoperative complications.