Local differences in electrogastrographic indices associated with total gastrectomy, total colectomy, distal gastrectomy and colonic replacement.

The electrogastrographic indices of spectral frequency, instability factor (IF), power amplitude, and power content (%) were compared between control subjects (C), and subjects following either total gastrectomy (TG), total colectomy (TC), distal gastrectomy (DG) or colonic replacement surgery (CR). In the fasting state, both the spectral frequency and IF of the epigastric 3-cycle per minute (cpm) group of the TC subjects were significantly lower than those indices in C, TG, DG, and CR subjects. In contrast, the power amplitude and power content of the epigastric 3-cpm group of both TG and DG subjects were significantly lower than those of C and TC subjects. The original epigastric waves of TG had remarkably high amplitudes. Furthermore, the absolute power of the epigastric 3-cpm of the TC subjects was 10 times higher than that in either the C or TG subjects. These results may be partially explained by the assumption that the recorded epigastric electrogastrography (EGG) is mainly contributed to by the 3-cpm myoelectric activity of the stomach and colon, while the infraumbilical EGG is mainly contributed to by the 3-cpm myoelectric activity of the colon. Topographic EGG maps visually supported these assumptions.