Approximately 300 million adults undergo surgical procedures worldwide each year.

In the United States, 30% of surgical patients are smokers Nicotine dependence increases 30-day mortality and the incidence of pulmonary complications after surgery.

Notably, postoperative pulmonary complications are more common than cardiac complications and lead to increased medical costs.

Long-term smokers are more likely to develop postoperative pulmonary complications because of airway secretions and sputum retention.

In addition, patients experiencing postoperative pain are not willing to breathe deeply or cough, which may increase the risk of pulmonary complications.

Therefore, postoperative analgesia is of critical importance for the rehabilitation of nicotine-dependent patients who undergo surgical procedures.