Lower esophageal pressure changes with tube gastrostomy: a causative factor of gastroesophageal reflux in children?

In children, Stamm tube gastrostomy can initiate gastroesophageal reflux (GER) or worsen preexisting GER. We identified a possible mechanism for this problem in 25 children with GER who had esophageal manometry performed in conjunction with an antireflux operation. Intraoperative lower esophageal high pressure zone (LEHPZ) pressure and length were recorded for a simulated gastrostomy in all patients prior to performing the antireflux operation. These same parameters were then recorded for a simulated (11 patients) or real gastrostomy (14 patients) following the antireflux procedure. The LEHPZ pressure decreased with simulated Stamm gastrostomy (7.8 +/- 1.1----6.6 +/- 1.1 mm Hg, NS: Normal = 11.2 +/- 0.9 mm Hg). This decrease was less significant than the decrease in LEHPZ length (1.1 +/- 0.1----0.8 +/- 0.1 cm, P less than .01: Normal = 1.3 +/- 0.1 cm). Following Boerema gastropexy, simulated gastrostomy produced a similar decrease in LEHPZ pressure (20.8 +/- 3.8----17.1 +/- 2.7 mm Hg, NS) and length (3.3 +/- 0.4----2.5 +/- 0.3 cm, P less than .025). The LEHPZ pressure and length were not decreased by real gastrostomy performed with modified Thal fundoplication or with Nissen fundoplication. Thus, a decrease in LEHPZ length may be one mechanism whereby GER is initiated or worsened by tube gastrostomy in children. Tube gastrostomy has a similar effect when performed with a Boerema gastropexy, but not when performed with a Nissen or modified Thal fundoplication.