Postoperative atelectasis: Pathophysiology, clinical importance, and principles of management

The pathophysiology of atelectasis has been admirably well defined in the past 30 years, but there remain unanswered questions with important clinical implications. What specific insults occur intraoperatively to disrupt the normal pattern of respiratory muscle action? What is the nature of diaphragmatic dysfunction after abdominal surgery? Does secretion retention precede or follow the onset of lung collapse? From a therapeutic standpoint, the precipitating factors, the major groups at risk, and the central principles of management are well understood. Optimal preventive methods of patient preparation, anesthesia, operative technique, and postoperative care must be established by well-designed clinical trials. A major challenge will be to apply current and future knowledge cost-effectively.