Myo-electrical and motor activity of the stomach in the first days after abdominal surgery: evaluation by electrogastrography and impedance gastrography.

The electrical and motor activities of the stomach were studied in the early postoperative phase after abdominal surgery by means of surface recording techniques: electrogastrography (EGG) and impedance gastrography (IGG). EGG and IGG recordings were made pre-operatively and on the first and second postoperative days. Physical signs and symptoms related to gastrointestinal motility were assessed. Two patient groups were studied; a group of patients undergoing cholecystectomy (n = 9) was compared with a group with major colonic surgery (n = 14). After colonic surgery, resumption of a normal oral diet was later and nausea and vomiting were seen more frequently than after cholecystectomy. Other physical signs concerning intestinal motility did not differ between the groups. Gastric myo-electrical activity (0.04-0.06 Hz), recorded electrogastrographically, tended to decrease in the postoperative phase in both groups, and return to pre-operative values later in the colonic surgery group. However, none of the differences reached statistical significance. Abnormal gastric activity (tachyarrhythmia) was observed in one pre-operative patient but in 6 patients (2 cholecystectomy, 4 colonic surgery) after operation. IGG variables were not significantly affected by the operation and were not significantly different between the groups. No correlation between the symptoms nausea and vomiting in the postoperative phase and the incidence of tachyarrhythmias could be demonstrated in this study. It is concluded that antral myo-electrical and motor activity, measured with non-invasive techniques (EGG and IGG), are not grossly abnormal on the first and second postoperative day after abdominal surgery. It is further concluded that abnormal gastric frequencies do not appear to play a major role in the genesis of postoperative nausea and vomiting.