Alteration of Lower Esophageal Sphincter Characteristics with Respiration and Proximal Esophageal Balloon Distention

Abstract

By using the manometric recording catheter as both a measuring stick and a pressure detecting device, the location, length, and magnitude of the lower esophageal high pressure zone (HPZ) were studied in healthy human subjects. The HPZ was found to be located 1 to 3 cm more distal at end-inspiration than at end-expiration. In both phases of respiration the mean length (3 cm) and magnitude (22 mm Hg) of the resting HPZ were similar. An upward movement of the HPZ followed distention of the proximal esophagus by a balloon, accompanied by a 40% shortening of the HPZ and a 65% decrease in its magnitude. Whereas the movement of a sphincter segment relative to the recording orifice during the respiratory cycle can explain the pressure fluctuations within the resting HPZ, a combination of positional change and diminished sphincter tone best explains the fall in pressure within the HPZ after balloon distention and, probably, after swallowing. In addition, it is possible that sphincter length, as well as sphincter magnitude, is an important determinant of sphincter competence.