This report gives the results of a cost-efficiency analysis of a prospective longitudinal study evaluating two forms of prophylaxis against postoperative pulmonary complications in 876 patients undergoing abdominal surgery. It cost $12.19 per patient for conventional chest physiotherapy, and equivalent costs accrue when incentive spirometers are recycled and used on average 2.3 times (in the Royal Perth Hospital, incentive spirometers are recycled an average of 4.7 times). Maximum cost-containment can be achieved by carefully selecting patients for physical chest care and then instigating a programme of perioperative chest care utilizing recycled incentive spirometers. This approach does not compromise the clinical benefits of prophylactic chest care and allows physiotherapy resources to be directed toward patients with established pulmonary problems.