Lower-esophageal sphincter function does not determine resting upper-esophageal sphincter pressure.

Records of 269 esophageal motility studies were reviewed to determine the relationship between lower-esophageal sphincter (LES) function and upper-esophageal sphincter (UES) pressure. Average and greatest UES pressures were similar in patients with LES pressures less than 10 mm Hg or greater than 20 mm Hg, and in patients with and without gastroesophageal reflux as determined by an intraesophageal pH electrode test. Although teliologically appealing, the belief that patients with weak lower-esophageal sphincters and gastroesophageal reflux have stronger upper-esophageal sphincters to guard against pharyngeal reflux and aspiration cannot be confirmed by current manometric techniques.