Dynamics of level of randomness of electrogastrograms can be indicative of gastric electrical uncoupling in dogs

Abstract

Gastric electrical uncoupling is the lack of electrical synchronization in different parts of the stomach. The aim of this study was to investigate the impact of gastric electrical uncoupling on the level of randomness of canine electrogastrograms (EGG). Electrogastrograms were obtained from 11 unconscious acute dogs. Gastric electrical uncoupling was produced surgically by performing two consecutive circumferential cuts through the entire thickness of the gastric muscle layer. Three separate 1/2-hr eight-channel bipolar EGGs were obtained from each dog in the basal state and after each cut. The signals were amplified using amplifiers with a flexible frequency range, digitized with 10-Hz sampling frequency, and 4.27-min portions of the digital EGGs were subjected to a turning point test for randomness. The number of turning points (NTPs) was determined from successive time intervals calculated from all EGG channels. Distributions of NTPs were calculated for each dog. An average NTPs (ANTP) for each dog in a given state (basal, after the first cut, and after the second cut) was calculated from the ANTPs of all channels. In six of 11 dogs the ANTP were greater after the first cut. The number rose to nine of 11 dogs after the second cut. In only 45% of the dogs were the ANTP distributions significantly different (P < 0.01) after the first cut (sensitivity 45%). After the second cut the sensitivity rose to 64%. In two specific EGG channels NTP distribution was significantly different (P < 0.01) in nine of 11 dogs (sensitivity: 82%) after the second cut. The dynamics of the level of randomness in EGG can be indicative of severe gastric electrical uncoupling. Some EGG channel configurations are more sensitive than others in recognizing gastric electrical uncoupling.