PubMed1989
The optimal methods of prophylaxis and therapy of postoperative respiratory complications in surgical patients are still open to discussion. In spite of numerous recent clinical investigations, there is still no specific and universally acceptable therapeutic concept. In our department, we identify patients at risk of pulmonary complications by adequate screening, i.e. medical history, physical examination, chest X-ray, and spirometry. In the postoperative period there are a sequence of stages starting with early mobilization, respiratory therapy (including incentive spirometry and IPPB), and when necessary, controlled mechanical ventilation. We have measured and documented the flows and volumes required of patients using various types of incentive spirometer. In addition, we review on the literature and describe our experience with the technique, handling, and organization of sustained maximal inspiration (SMI). After thoracic or major upper abdominal surgery, all lung volumes decrease due to impairment of rib cage movement, changes in chest wall muscle tone, an increase in lung recoil, and airway closure. At the end of each expiration some of the smallest airways collapse either partly or totally. This process continues to some extent until, normally, a deep breath recruits the alveoli. Sighs to the limit of total lung capacity or oscillations of the expiratory baseline ought to be responsible for this effect in healthy humans; the same purpose is intended in incentive spirometry. For this therapy, it is mandatory that the central airways are not occluded by mucus and that the patient is able to breath volumes exceeding his normal tidal volume.(ABSTRACT TRUNCATED AT 250 WORDS)