title: [Measurement of gastric mucosal pH by tonometry in major abdominal surgery].
abstract: OBJECTIVE
  To investigate whether changes in gastric intramucosal pH (pHim) occur during major abdominal surgery, and if so, to determine the relationship between classic global indices of tissue perfusion such as mean arterial blood pressure (MAP), heart rate (HR), central venous pressure (CVP), urine flow (UF) and arterial pH (pHa).
  
  
  METHODS
  Prospective descriptive study.
  
  
  METHODS
  Seven ASA2 patients undergoing major abdominal surgery.
  
  
  METHODS
  After induction of anaesthesia and endotracheal intubation, a tonometer nasogastric tube was positioned in the stomach. Measurements of tonometric PCO2 (PCO2ss), end-tidal PCO2 (PETCO2), PaCO2, bicarbonates [bicarb], pHa, MAP, HR, CVP and UF were collected at baseline (HO), and one, two, three, and 24 hours (H1, H2, H3, and H24) after the beginning of surgery.
  
  
  RESULTS
  Haemodynamics did not significantly change during anaesthesia. During recovery HR increased and CVP decreased significantly. The pHim decreased significantly from 7.42 +/- 0.03 at H0 to 7.30 +/- 0.02 at H3. This was associated with a significant decrease in pHa (from 7.43 +/- 0.02 at H0 to 7.33 +/- 0.02 at H3) and in [bicarbo] from 22 +/- 1 mmol at H0 to 20 +/- 1 mmol at H3). The PaCO2 increased significantly from 33.5 +/- 1.5 mmHg at H0 to 39.5 +/- 2.8 at H3. On the other hand, pHimcorr (7.40- (pHa-pHim) and delta CO2 (PCO2ss-PETCO2) did not vary during anaesthesia. Postoperative organ failure did not occur in these patients.
  
  
  CONCLUSIONS
  The pHim may decrease during anaesthesia without evidence of abnormal tissue perfusion. In order to avoid.
authors.affiliation: Département d'anesthésie-réanimation chirurgicale 2, CHRU, hôpital Claude-Huriez, Lille, France.
authors.forename: J
authors.initials: J
authors.lastname: Leclerc
authors.forename: B
authors.initials: B
authors.lastname: Vallet
authors.forename: C
authors.initials: C
authors.lastname: Deswarte
authors.forename: S
authors.initials: S
authors.lastname: Charré
authors.forename: M
authors.initials: M
authors.lastname: Fleyfel
authors.forename: P
authors.initials: P
authors.lastname: Petillot
authors.forename: P
authors.initials: P
authors.lastname: Scherpereel
mesh_terms: D000005:Abdomen / Q000601:surgery*; D002245:Carbon Dioxide / Q000032:analysis; D005745:Gastric Acidity Determination / Q000295:instrumentation; D005753:Gastric Mucosa / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D016343:Monitoring, Intraoperative
chemical_list: D002245:Carbon Dioxide