Influence of breathing pattern on the esophagogastric junction pressure and esophageal transit. Mittal, Ravinder K., Hubert A. Shaffer, Stella Parollisi, Lane Baggett. DEPARTMENTS OF INTERNAL MEDICINE AND RADIOLOGY, UNIVERSITY OF VIRGINIA HEALTH SCIENCE CENTER, CHARLOTTESVILLE VIRGINIA 22908.
APStracts 2:0101G, 1995.
BACKGROUND: The esophagogastric junction (EGJ) is guarded by two sphincters, a smooth muscle lower esophageal sphincter (LES) and a skeletal muscle crural diaphragm. The LES relaxes in response to a swallow but the crural diaphragm does not. Since contraction of crural diaphragm is affected by pattern of breathing, the latter may also influence the EGJ pressure and swallow induced EGJ relaxation. AIMS: Our aims were to study the effects of alterations of the breathing pattern on the EGJ pressure, swallow induced EGJ relaxation and esophageal transport of liquid bolus. METHODS: Manometric, electromyographic and videoflouroscopic studies were performed in 12 healthy subjects. The subjects were trained in two types of breathing patterns, hyperventilation and partial expiration, using the visual biofeedback from their own respiratory waveform. RESULTS: Hyperventilation increased the frequency of inspiratory pressure oscillations at the EGJ without affecting the end-expiratory EGJ pressure. Partial expiration resulted in an increase in the end -expiratory EGJ pressure. Swallow induced relaxation at the EGJ was markedly reduced during partial expiration. An inspiration during a swallow (control breathing and hyperventilation) caused transient interruption of flow across the EGJ. Partial expiration resulted in cessation of the flow across the EGJ, failure of esophageal peristalsis to traverse the entire length of the esophagus, increased esophageal transit time and incomplete esophageal clearance of a liquid bolus. The frequency of bipeaked esophageal contractions was significantly increased during hyperventilation and partial expiration. CONCLUSION: The breathing patterns of partial expiration and hyperventilation have significant influence on esophageal motor function. Abnormal breathing pattern may be involved in the pathogenesis of esophageal motor dysfunction.

Received 23 November 1994; accepted in final form 5 May 1995.
APS Manuscript Number G462-4.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 30 May 1995.