Intra-Enteric Pressure in Experimental and Clinical Intestinal Obstruction. ∗

Abstract

As a preliminary to a series of experiments on the effect of increased intra-enteric pressure upon the physiology and structure of the bowel wall, occasion was taken to measure the levels of sustained pressure which obtained in the intestine of dogs with low ileal obstruction.

The intra-enteric pressure was determined in 19 dogs with low ileal type of obstruction of one to 7 days duration. Simple obstruction was produced by sectioning the terminal ileum and inverting both ends. At the stated duration of obstruction, the animals were anesthetized, the abdomen opened, and a large calibre needle connected to a water manometer was inserted into the lumen of the obstructed ileum. Pressure readings ranged from 4 to 19 cm. of water, or roughly 4 times the normal. Active peristalsis was always observed even after 7 days of obstruction. The intraenteric pressure in this series apparently increased with the duration of the obstruction. It was observed that the sustained pressure in low ileal obstruction was seldom above 14 cm. of water (Table I).

On 6 additional dogs, 17 measurements of intra-enteric pressure were made at varying intervals after the establishment of obstruction in the following manner. A loop of gut of 3 to 4 inches in length was brought up on the abdominal wall and the adjacent skin was mobilized to cover it. When this satchel-like handle was well healed, complete obstruction was accomplished by inverting the ends of the severed terminal ileum. In a few instances 2 such subcutaneous loops were made in the same dog. The usual sustained intra-enteric pressure found varied between 6 and 8 cm. of water. The highest reading obtained was 17 cm. of water. These pressures are in accord with the findings of Owings and his associates. 1

Opportunity has also been afforded to determine the intra-enteric pressures in 5 clinical cases of obstruction of the small bowel of mechanical origin. Pressures were determined at the time of operation (enterostomy) by connecting the enterostomy tube to a water manometer.