Comparative assessment of power dynamics of gastric electrical activity

This study was undertaken to investigate the correlation between power dynamics of gastric electrical activity (GEA) assessed with different recording techniques. A total of seven eight-channel 1-hr combined recordings were obtained from three subjects in five consecutive postoperative days. Four channels were recorded from bipolar electrodes implanted into the gastric antral wall, and four channels were electrogastrographic (EGG). Six pairs of bipolar electrodes were inserted into the antral wall (three anterior; three posterior) of 16 anaesthetized dogs. Fourteen-channel (six internal GEA and eight EGG) 1/2-hr recordings were obtained from each dog. Sets of power values calculated from channel pairs (internal, EGG or mixed) were cross-correlated and the significance of the obtained correlation coefficients was examined (P < 0.05). The majority of power correlations of internal GEA channel pairs, and those of mixed (internal GEA-EGG) channel pairs were insignificant. These findings question the claims that EGG power dynamics mirrors the power dynamics of internal GEA.