Bronchial mucus transport in chronic smokers and nonsmokers during general anesthesia

Abstract

Study Objective: To compare bronchial mucus transport velocity in smokers and nonsmokers. Design: Prospective consecutive-sample trial. Setting: University hospital. Patients: 12 smokers and 22 nonsmokers undergoing major abdominal or thoracic surgery with postoperative mechanical ventilation. Interventions: After the end of the operation, bronchial mucus transport velocity was measured with a small volume (0.05 to 0.08 ml) of technetium 99-m labeled albumin microspheres with an activity of 1.5 MBq. The radiolabeled bolus was deposited on the dorsal mucosal surface at the distal end of the right and left main bronchus via flexible bronchoscopy. The movement of the microspheres toward the trachea was visualized and recorded using a scintillation camera. Quantitative evaluation was based on the pathtime diagram. After determination of bronchial mucus transport velocity, patients were examined daily over 4 days to record pulmonary complications (retention of secretion and nosocomial pneumonia). Measurements and Main Results: Smokers were comparable to nonsmokers with respect to age, preoperative lung function tests, body temperature, duration of mechanical ventilation, dose of anesthetics, and intraoperative blood loss. Smokers had a significantly slower bronchial mucus transport velocity compared with nonsmokers: in the left bronchus, 1.3 mm/min (0 to 9.6 mm/min) (median with range) versus 9.7 mm/min (3.7 to 15.3 mm/min) ( p < 0.001); in the right bronchus, 2.5 mm/min (0 to 16.0 mm/min) versus 8.3 mm/min (5.5 to 15.3 mm/min) ( p < 0.01). Pulmonary complications occurred in 4 smokers and 1 nonsmoker. Conclusions: When measured during general anesthesia, smokers have a slower bronchial mucus transport than nonsmokers. This may be related to postoperative pulmonary complications in smokers.