title: Postprandial proximal gastric acid pocket in patients after Roux-en-Y gastric bypass.
abstract: BACKGROUND
  An unbuffered postprandial proximal gastric acid pocket (PPGAP) has been noticed in normal individuals and patients with gastroesophageal reflux disease (GERD). The role of gastric anatomy in the physiology of the PPGAP remains unclear. It is also unclear whether operations that control GERD, such as Roux-en-Y gastric bypass (RYGB) and Nissen fundoplication, change the PPGAP.
  
  
  OBJECTIVE
  This study aims to analyze the presence of PPGAP in patients submitted to RYGB.
  
  
  METHODS
  Fifteen patients who had a RYGB for morbid obesity (mean age 53 years, 14 females, mean time from operation 3 years) were studied. All patients were free of foregut symptoms. Patients underwent a high-resolution manometry to identify the location of the lower border of the lower esophageal sphincter (LBLES). A station pull-through pH monitoring was performed from 5 cm below the LBLES to the LBLES in increments of 1 cm in a fasting state and 10 min after a standardized fatty meal (40 g of chocolate, 50% fat).
  
  
  RESULTS
  Acidity was not detected in the stomach of four patients before meal. After meal, PPGAP was not found in eight patients. In three patients, a PPGAP was noted with an extension of 1 to 3 cm.
  
  
  CONCLUSIONS
  PPGAP is present in a minority of patients after RYGB; this finding may explain part of the GERD control after RYGB and that the gastric fundus may play a role in the genesis of the PPGAP.
authors: Department of Surgery, Escola Paulista de Medicina, Federal University of São Paulo, São Paulo, Brazil. herbella.dcir@epm.br
authors: Fernando A M
authors: FA
authors: Herbella
authors: Fernando P P
authors: FP
authors: Vicentine
authors: Jose C
authors: JC
authors: Del Grande
authors: Marco G
authors: MG
authors: Patti
authors: Carlos H
authors: CH
authors: Arasaki
mesh_terms: D000328:Adult; D005260:Female; D005744:Gastric Acid / Q000378:metabolism*; D005745:Gastric Acidity Determination; D015390:Gastric Bypass / Q000009:adverse effects*; D005753:Gastric Mucosa / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000601:surgery*; D019518:Postprandial Period