Effect of increased intraabdominal pressure on lower esophageal sphincter pressure

Abstract

This study evaluates the effect of intraabdominal pressure increases on lower esophageal sphincter (LES) pressure in normal subjects and in patients with reflux esophagitis. Intraabdominal and intragastric pressure were increased by abdominal compression, the Valsalva maneuver, and leg raising. In normal subjects changes in pressure recorded from the LES equaled the changes in gastric pressure induced by abdominal compression and Valsalva. Consquently the LES-gastric pressure gradient remained unchanged. During leg raising, pressure recorded from the LES increased more than gastric pressure, thereby increasing the LES-gastric pressure gradient. Although statistically significant, the LES pressure increases associated with leg raising were modest, unrelated to initial sphincter pressure, and unaffected by atropine. When individuals demonstrating a "common cavity" phenomenon were exculed, LES pressure changes during abdominal compression were similar in patients with esophagitis and in normal volunteers. Consequently, response of the LES to abdominal compression generally does not separate patients with esophagitis from normal subjects. We believe that the LES responses to increased intra-abdominal pressure observed in this study are better accounted for by mechanical factors than by a physiologic adaptive response of intrinsic LES tone.

Abdominal Compression by Waist Belt Aggravates Gastroesophageal Reflux, Primarily by Impairing Esophageal Clearance

“…In our current study after the meal the belt caused a greater rise in the IGP than in LES pressure causing a significant fall in LES pressure relative to the IGP which is the pressure gradient preventing reflux. This fall in LES pressure relative to the IGP has been reported by some but not all investigators (5,7,8,9,10,11). The fall in LES pressure relative to the IGP in our current study was only apparent after the meal and involved patients with reflux disease and in these respects differed from previous studies.…”

“…Previous investigators have examined the effect of waist belt compression on the manometric characteristics of the lower esophageal sphincter (LES) in both healthy volunteers and patients with reflux disease. The rise in IGP caused by the waist belt is accompanied by a rise in LES pressure though sometimes of a lesser magnitude (5,7,8,9,10,11). Waist belt compression in short term studies does not result in the development of, or aggravation of, hiatus hernia or in increased separation of the intrinsic and extrinsic components of the LES (9,12,13).…”

Ontogenic Studies of Gastrointestinal Function. II. Lower Esophageal Sphincter Maturation in Neonatal Beagle Puppies

“…On the other hand, the increase in the LES-GF intraluminal pressure gradient during gastric contractions may be due to an enhanced responsiveness of the muscle to various neural inputs. Reflex contraction of the LES occurs with abdominal compression or in association with contractions of the stomach (7,9,21). There is evidence that the increase in LES intraluminal pressure during gastric contraction is mediated by a neural reflex which involves a cholinergic component (1,21).…”

Lower Esophageal Sphincter and Acupuncture: Electromanometric Evaluation in Esophageal Achalasia

“…The manometric catheter was passed through the nostrils into the stomach and drawn into the LES with the rapid pull-through system [10], while the patient suspended respiration at the end of a normal expiration.…”