Effect of acute gastric dilatation on gastric myoelectric and motor activity in dogs

Abstract

Objective-To investigate the effects of experimentally induced acute gastric dilatation on electrical and mechanical activities of the stomach in dogs. Animals - 7 healthy dogs. Procedure - Electrodes and strain-gauge force transducers were implanted on the serosal surface of the antrum and pylorus, Eight days later, baseline gastric electrical and contractile activities were recorded. The dogs were anesthetized and mechanically ventilated to maintain normocapnia while the stomach was distended (intragastric pressure, 30 mm Hg) for 180 minutes, using a thin compliant bag. Gastric electrical and contractile activities were recorded again on days 1 and 10 after dilatation. Recordings were analyzed to determine gastric slow-wave frequency, slow-wave dysrhythmia, propagation velocity of slow-waves, coupling of contractions to slow waves, motility index on the basis of relative contractile amplitudes, and onset of contractions after a standardized meal. Results - Electrical or contractile activities were not significantly different 18 hours after acute gastric dilatation (day 1). Arrhythmias were evident before and after gastric dilatation in dogs from which food was withheld and in dogs after consumption of a meal. Conclusions - Variables for assessing gastric electrical and contractile activities were unaffected 18 hours after acute gastric dilatation. Clinical Relevance - Analysis of results of this study indicated that altered electrical and contractile activities in dogs with short-term gastric dilatation are not likely to be secondary to the process of acute gastric dilatation.