[Respiratory function in patients immediately after surgery of the thorax or upper abdomen]

The study deals with the patients in the first postoperative hour following the operation in the upper abdomen or thorax. We considered the respiratory function of the patients in the first postoperative hour and how the respiratory function is influenced by the residua of general anesthesia at that time. Statistically significant decrease of postoperative SaO2 values was found and many patients were hypoxemic after the operation. We found decreased minute ventilation in the first postoperative hour in both groups of patients. Anyway the minute ventilation was more decreased in the abdominal group of patients who recovered from intravenous anesthesia. The conscience as well was more slowly returned to the patients in the abdominal group. In the first 30 minutes more abdominal patients suffered from the muscular weakness following intraoperative relaxation. But this first half an hour after the operation they had satisfactory level of analgesia left. To the contrary the postoperative pain was more severe in the thoracal group of patients. Postoperative gas exchange was more often and more seriously disturbed in the thoracal group of patients who in majority suffered from previous lung disease, which means they had greater ventilation/perfusion imbalance and greater right to left shunt. In the abdominal group only the patients who had relatively short intravenous anesthesia were found hypoxemic in the first postoperative hour. We think that in these patients the gas exchange abnormalities immediately after the operation are also caused by the hypoventilation which often follows general anesthesia.