title: Gastroesophageal reflux and tracheal contamination during laparoscopic cholecystectomy and diagnostic gynecological laparoscopy.
abstract: Laparoscopy causes an increase in intraabdominal pressure and may lead to an increase in gastroesophageal reflux (GER). We designed this study to assess and compare the frequency of GER and tracheal contamination in patients undergoing laparoscopic cholecystectomy (LC) and gynecological laparoscopy (LG). We studied 20 LC and 17 LG patients. The pH was measured using monocrystalline antimony pH electrodes positioned in the middle to upper esophagus and on the posterior wall of the trachea distal to the tip of the endotracheal tube. Acid reflux was defined as a decrease in esophageal pH to 4.0 or less. Alkaline reflux was defined as an abrupt increase in esophageal pH of more than 1.0, not associated with previous acid reflux. More than 80% of all patients at baseline had a gastric pH < or = 2. Overall, acid GER alone occurred in 47% patients in the LG group and in 15% patients in the LC group. During recovery, a larger proportion of patients had acid reflux in the LG group (47%) than in the LC group (10%). In contrast, alkaline reflux occurred in 75% of LC patients and 11.7% of LG patients. After cholecystectomy, there is an acute increase in the incidence of alkaline reflux. This alkaline reflux may be due to duodenogastric reflux resulting in an alkaline gastric shift.
  
  
  CONCLUSIONS
  We studied the incidence of reflux of stomach contents in patients undergoing laparoscopic (keyhole) surgery for cholecystectomy or gynecology, using pH probes in the esophagus (gullet) and the trachea (windpipe). Acid reflux was very common but did not pass into the trachea. After gallbladder removal, the refluxed material became alkaline.
authors.affiliation: Department of Anesthesia & Intensive Care, St. Vincent's Hospital, Elm Park, Dublin, Ireland.
authors.forename: M T
authors.initials: MT
authors.lastname: Doyle
authors.forename: C F
authors.initials: CF
authors.lastname: Twomey
authors.forename: T M
authors.initials: TM
authors.lastname: Owens
authors.forename: A J
authors.initials: AJ
authors.lastname: McShane
mesh_terms: D000328:Adult; D002763:Cholecystectomy; D004947:Esophagus / Q000502:physiology; D005260:Female; D005764:Gastroesophageal Reflux / Q000209:etiology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D010535:Laparoscopy / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D013997:Time Factors; D014132:Trachea / Q000502:physiology