Motor abnormality in the gastroduodenal junction in patients with infantile hypertrophic pyloric stenosis

Background/Purpose: Periodic clusters of phasic pressure waves in the gastr oduodenal junction (GDJ) have been seen in patients with infantile hypertro phic pyloric stenosis (IHPS). This study investigated the details of these pressure waves in relation to disturbed transpyloric flow in IHPS. Methods: Manometric study was performed in 11 IHPS patients before and afte r atropine therapy and 2 non-IHPS infants, Pressure changes in the GDJ were measured with an 8-channel sleeve or a 9-channel sidehole micromanometric assembly under fluoroscopic control for 2 hours. Results: Clusters of phasic pressure waves (365 +/- 42 mm Hg) associated wi th an increase in basal pressure (10 +/- 3 mm Hg) were intermittently obser ved in the GDJ in all IHPS patients. Similar observations were not made in the non-IHPS infants. Most antral pressure waves occurred simultaneously wi th those pressure waves in the GDJ in the IHPS patients. Atropine (0.01 mg/ kg) transiently abolished the phasic and tonic pressure waves for 19 +/- 10 minutes. Significantly fewer phasic pressure waves were observed after atr opine therapy. Conclusions: Characteristic phasic and tonic contractile activity in the GD J is uncoordinated with the antral contractions in IHPS patients. Such inco ordination may be an important factor in the disturbed transpyloric flow in IHPS. J Pediatr Surg 36.,1641-1645. Copyright (C) 2001 by W.B. Saunders Co mpany.