title: [Intraoperative monitoring of gastric intramucosal pH].
abstract: BACKGROUND
  Gastric mucosal pH may be a good indicator of splanchnic tissue oxygenation.
  
  
  OBJECTIVE
  To study the effects of abdominal surgical procedures on gastric mucosal pH.
  
  
  METHODS
  Eighteen patients subjected to abdominal surgery were studied. All patients received general anesthesia and hemodynamic parameters were maintained within 20% of basal values. A tonometer was placed in the stomach after induction of anesthesia. Arterial blood gases and samples from the tonometer were obtained 30 minutes after induction and at 2 hours of surgery. Intramucosal pH was calculated using Henderson-Haselbach equations.
  
  
  RESULTS
  Basal gastric mucosal pH was 7.4 +/- 0.1 and did not change during surgery. Two patients had a pH persistently below 7.35 without hemodynamic alterations or systemic acidosis.
  
  
  CONCLUSIONS
  Gastric mucosal pH is not modified by abdominal surgery and some patients have low values despite the absence of hemodynamic derangement.
authors.affiliation: Departamento de Anestesiología, Hospital Clínico, Universidad Católica de Chile, Santiago de Chile.
authors.forename: M
authors.initials: M
authors.lastname: Concha
authors.forename: R
authors.initials: R
authors.lastname: Añazco
authors.forename: A
authors.initials: A
authors.lastname: González
authors.forename: D
authors.initials: D
authors.lastname: Becker
authors.forename: A
authors.initials: A
authors.lastname: Gajardo
mesh_terms: D000005:Abdomen / Q000601:surgery*; D000704:Analysis of Variance; D005260:Female; D005745:Gastric Acidity Determination; D005753:Gastric Mucosa / Q000378:metabolism*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D011446:Prospective Studies