Esophageal peristaltic force in man

Abstract

The purposes of this study were: (1) to quantify human esophageal peristaltic force, (2) to determine the factors which alter this force, and (3) to evaluate the relationship between force and intraluminal pressure. Force was measured in normals by using a mercury-in-Silastic strain gauge. Simultaneous pressures were obtained through constantly infused open-tipped catheters. On separate days a sphere of either 6.0-, 9.0-, or 13.0-mm diameter was attached to the strain gauge and measurements were obtained at three esophageal levels. Studies were done (1) with the subject at rest, (2) while performing a Valsalva maneuver, (3) during the administration of bethanechol, and (4) after intravenous atropine. Peristaltic force increased directly with sphere size but inversely with distance from the lower esophageal sphincter. Intraluminal pressure did not change significantly with sphere size or at different levels of the esophagus. A Valsalva maneuver increased force and pressure significantly only in the distal esophagus. Bethanechol (0.1 mg/kg) had no significant effect on force at any esophageal level, but atropine (0.01 mg/kg) decreased force at each esophageal level and with each sphere size. The distal esophageal response to a Valsalva maneuver was lost following atropine. Intraluminal pressure was a good index of peristaltic force, providing sphere size and esophageal level remained unaltered. These studies suggest that esophageal peristaltic force may be altered by: (1) bolus size, (2) extrinsic maneuvers which alter intraluminal pressure (Valsalva maneuver), and (3) certain pharmacological agents.