Canadian Journal of Anesthesia, Vol 28, 305-313, Copyright © 1981 by Canadian Anesthesiologists' Society

Pulmonary Atelectasis After Anaesthesia: Pathophysiology and Management

¹ Department of Anaesthesia, McMaster University

Dr. John R.A. Rigg, W.K. Kellogg Centre For Advanced Studies In Health Sciences, Western Australian Institute of Technology, Hay man Road, South Bentley, Western Australia, 6102.

The pathophysiological basis of pulmonary atelectasis is reviewed and risk factors that enhance lung collapse are discussed. Management strategies to reduce or eliminate risk factors and to prevent collapse are discussed and the rational bases of these strategies are identified.

Instability of lung alveoli is a consequence of surface tension and regional differences in alveolar size. The inherent tendency of alveoli to collapse is enhanced by the following risk factors; low lung volume, high closing volume, oxygen therapy, a rapid shallow ventilatory pattern, chronic lung disease, smoking, obesity, postoperative pain following abdominal or thoracic surgery, narcotic induced ventilatory depression, and neurological, neuromuscular, muscular and musculoskeletal diseases associated with mechanical impairment of respiratory function. The primary goal of perioperative respiratory management is prevention of atelectasis. Appropriate management strategies include physiotherapy and delay of elective surgery if substantial improvement in respiratory status can be achieved by specific treatments such as antibiotics, bronchodilators, steroids, and reduction of tobacco use and caloric intake. In selected cases, elective postoperative controlled ventilation may be indicated.

Key Words: ANAESTHESIA, COMPLICATIONS, atelectasis • LUNG, atelectasis