The Experimental Studies Related to the Lower Esophageal High Pressure Zone in Dogs

Abstract

We produced a new 5-lumen manometric catheter with an outer diameter of 6mm. The catheter has four radial recording lumens which have each a side-hole orifice at the same level, 2 mm above the distal end, and one central recording lumen which has a end-hole orifice. The tone and the length of high pressure zone in 14 dogs were measured by use of this catheter with constant perfusion of water at a rate of 30 ml/hr. The results were as follows: 1. Radial asymmetry of high pressure zone was significant in dogs, thus the left-posterior pressure was the biggest and the right-anterior pressure was minimum. 2. The tone obtained from the end-hole catheter (Y) was well correlated to about 70% of the mean value from four side-hole catheters (X). Y=0.67X+7.9 3. The lenghth of high pressure zone from the end-hole (Y) was also correlated to the mean length of four side-holes (X). Y=0.39X+4.3 We speculated upon the mechanism in tracing of high pressure zone, and obtained the following conclusion. The value obtained with the end-hole catheter would correspond to the true opening pressure of gastro-esophageal junction, whereas the value obtained with the side-hole catheter might be higher than the resting tone, because the wall of gastro-esophageal junction can be stretched by the catheter during the tracing, and it would produce the increase in the wall tension.