Incidence and degree of hypoxemia after gynecological surgery.

Arterial blood gases and pH values were determined before and after performing abdominal hysterectomies in 32 women. Four to five liters of oxygen were given by nasal cannula to 15 patients, while 17 patients breathed only ambient air. Falls of arterial oxygen tension averaging 10 torrs were seen up to 30 minutes after surgery in the latter group, but no apparent hypoxemia occurred in the patients who received nasal oxygen. Postoperative mild hypoxemia present in patients undergoing pelvic surgery can be obviated by prophylactic administration of oxygen at low flows.