Postprandial antral hypomotility in patients with idiopathic nausea and vomiting.

The pathogenesis of idiopathic nausea and vomiting is poorly understood and could involve disorders of gut motility. The contractile activity of the stomach and small bowel was studied in 20 patients (seven men) with nausea and vomiting for longer than six months. None had previous gastric surgery, mechanical obstruction and metabolic causes were excluded. Fasting (four hours) and fed (up to two hours) contractile activity was recorded by a low compliance infusion system from the gastric antrum (four sites), the duodenum and the jejunum. Normal criteria were established in seven healthy controls. During fasting, from one to three (median 2) migrating motor complexes (MMC's) were present in patients and controls. Only two patients had contractile abnormalities during fasting. After a solid-liquid test meal, the contractility of the gastric antrum (quantified electronically as a cumulative motility index for 60 minutes) was significantly impaired in patients (p = 0.012). Six patients had normal qualitative and quantitative antral activity but two of them had 'phrase III-like fasting activity' in the small bowel after the test meal. Postprandial antral hypomotility was identified as a major abnormality in patients with unexplained nausea and vomiting.