[Hypoxemia after general anesthesia in healthy adults]

It has been shown that a variable percentage of patients who receive a general anesthetic are significantly hypoxemic when they arrive at the recovery room. Pulse oximetry has proved to be a reliable method to determine arterial oxygen saturation when compared to arterial or mixed venous blood oxygen saturation measurements. The authors determined the incidence and severity of hypoxemia by pulse oximetry in 45 healthy adult patients, (non obese, non smokers) who underwent non thoracic surgery under general anesthesia. Arterial oxygen saturation was measured without premedication before surgery (control), when they arrived at the recovery room, and 5 and 15 minutes later. The axillary temperature was taken at the same times. The results were expressed as the median and standard deviation and were analyzed with Student T Test, and p LO.05 was considered significant. Nine patients (20%) showed unacceptable oxygen saturation when they arrived at the recovery room (88.4 +/- 2.50%, LO.05). All patients showed significant hypothermia (35.3 +/- 0.54 degrees C). The authors conclude that a significant number of healthy adult patients who are given a general anesthetic show severe hypoxemia when they arrive at the recovery room. The severe hypothermia found in these patients can aggravate the hypoxemia. They consider it is mandatory to control the temperature of and to administer oxygen in the recovery room to all patients who receive a general anesthetic.