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

Objective-To investigate the effects of experimentally induced acute gastri c 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 t he serosal surface of the antrum and pylorus. Eight days later, baseline ga stric electrical and contractile activities were recorded. The dogs were an esthetized and mechanically ventilated to maintain normocapnia while the st omach was distended (intragastric pressure, 30 mm Hg) for 180 minutes, usin g 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, propagatio n velocity of slow-waves, coupling of contractions to slow waves, motility index on the basis of relative contractile amplitudes, and onset of contrac tions after a standardized meal. Results-Electrical or contractile activities were not significantly differe nt 18 hours after acute gastric dilatation (day 1). Arrhythmias were eviden t 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 acti vities 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 dila tation are not likely to be secondary to the process of acute gastric dilat ation.