title: [Effect of assisted ventilation and position on gastro-esophageal acid reflux after laparotomy].
abstract: OBJECTIVE
  Gastro-esophageal reflux disease (GERD) is frequent in mechanically ventilated patients, often source of hemorragic or respiratory complications. The aim of this study was to determine promoting factors for acid reflux and to define the role of methods of ventilation and body position on reflux.
  
  
  METHODS
  Fifteen patients with no history of GERD were included, following scheduled abdominal surgery. Reflux was measured in the proximal and distal esophagus by pH-metry. Events associated with reflux were detected by a videocamera linked to a videocassette recorder synchronized to the pH data logger. Position of the patients was randomized between supine and recumbent 30 degrees. Patients were first placed on mechanical ventilation then breathed spontaneously, determining 2 periods of equal duration during which provocative maneuvers were carried out.
  
  
  RESULTS
  Acid reflux was absent in recumbent 30 degrees posture. Acid contact time and number of reflux in supine posture were 0.5 +/- 0.4% and 0.3 +/- 0.2/h respectively with mechanical ventilation and 4 +/- 2.5% and 1 +/- 0.5/h respectively with spontaneous breathing (P<0.05 vs position 30 degrees ) in distal esophagus. Twenty-five% of reflux episodes were associated with an event, mainly cough.
  
  
  CONCLUSIONS
  Acid reflux is rare immediately following laparotomy. Seventy-five per cent of reflux occurred without any detectable event. Reflux was absent in semi recumbency. Mechanical ventilation did not facilitate reflux.
authors.affiliation: Service d'Hépato-Gastroentérologie et Alcoologie, Hôpital Carémeau, CHU Nîmes. philippe.pouderoux@chu-nimes.fr
authors.forename: Philippe
authors.initials: P
authors.lastname: Pouderoux
authors.forename: Eric
authors.initials: E
authors.lastname: Verdier
authors.forename: Laurent
authors.initials: L
authors.lastname: Muller
authors.forename: Mohammed
authors.initials: M
authors.lastname: Benbabbaali
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Lefrant
authors.forename: Pierre
authors.initials: P
authors.lastname: Barbaste
authors.forename: Gilbert
authors.initials: G
authors.lastname: Saissi
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Balmès
mesh_terms: D000368:Aged; D003371:Cough / Q000150:complications; D005260:Female; D005745:Gastric Acidity Determination; D005764:Gastroesophageal Reflux / Q000175:diagnosis / Q000209:etiology* / Q000517:prevention & control*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007813:Laparotomy / Q000009:adverse effects*; D008297:Male; D008365:Manometry / Q000379:methods; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods; D009325:Nausea / Q000150:complications; D011182:Postoperative Care / Q000379:methods; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology* / Q000517:prevention & control*; D011187:Posture; D012121:Respiration, Artificial / Q000009:adverse effects* / Q000379:methods*; D012307:Risk Factors; D013396:Suction / Q000009:adverse effects; D013997:Time Factors; D016896:Treatment Outcome; D014743:Videotape Recording / Q000379:methods