Electromyographic Observation of Intestinal Movement during Intestinal Obstruction.

Narrowing of the intestinal lumen and a circulatory disturbance are the two basic factors involved in intestinal obstruction. This paper analyzes the effect of each of these factors upon the motility of the canine intestine by means of electromyography during experimentally induced mechanical obstruction and vascular occlusion. EMG in simple mechanical obstruction is characterized by an increase followed by a decrease in the intensity of spike discharges, in which course there is a period where a group of intensified spike bursts and a resting interval appear alternately. The change in EMG on vascular occlusion also con sists of intensification and subsequent debilitation of the discharges, but on this occasion the progress is quite rapid and the resting interval is never observed. EMG on strangulating obstruction includes the manifestation of mechanical obstruction and that of vascular occlusion, and the former is prevalent in the case of mild strangulation and the latter in the case of acute, complete strangula tion. The ease with which the intestine resumes its motility on removal of the cause of intestinal obstruction largely depends on the duration of obstruction, the maximum duration assuring a complete recovery being approximately 24 hours for simple mechanical obstruction and about two hours for vascular occlusion.