Lower esophageal sphincter reacts against intraabdominal pressure in children with symptoms of gastroesophageal reflux

Studies of the effect of increased intraabdominal pressure on the lower esophageal sphincter (LES) are controversial. This study aimed to verify the LES competence against extrinsic abdominal compression in children with and without symptoms of gastroesophageal reflux (GER). Eighteen children ages 6-20 months were evaluated, 11 of them with symptoms of GER (group I) and 7 without symptoms of GER (group II). Manometry of the esophagus, LES, and stomach was performed in all children who underwent extrinsic abdominal compressions of 20, 40, 60, and 80 mm Hg. The pressure gradients in the esophagus, LES, and stomach were measured. The pressure gradient showed a significant difference only in the esophagus after extrinsic abdominal compressions of 60 mm Hg [group I median (range): 7.6mm Hg (2.7-20.0) vs group II: 2.8 mm Hg (1.4-9.6), P < 0.05], and 80 mm Hg [group I median (range): 7.7 mm Hg (3.7-28.9) vs group II: 3.8 mm Hg (1.2-21.1), P < 0.05]. It was concluded that the competence of LES to contain increased intraabdominal pressure might be an important factor in the pathophysiology of GER in children.