title: Gastroesophageal reflux and tracheobronchial contamination after cardiac surgery: should a nasogastric tube be routine?
abstract: Nasogastric (NG) tubes are routinely used in patients undergoing cardiac surgery. This randomized study was designed to assess gastroesophageal reflux (GER) without a NG tube (control) compared with a NG tube managed either by gravity drainage (gravity) or continuous low-grade suction (suction). Antimony pH probes were placed in the lower esophagus and trachea after induction of anesthesia in 51 patients, and pH was recorded every 5 s until the time of tracheal extubation. GER was defined as reversible decrease in esophageal pH to less than 4.0. No significant difference was found between groups in age, weight, gender, duration of postoperative ventilation, morphine use, or antiemetic use. All indicators of GER were seen more frequently in the gravity group compared with the two other groups (P < 0.001). One episode of sudden decrease in tracheal pH was observed in a patient in the gravity group, indicating tracheal aspiration, which was associated with delayed extubation and postoperative pneumonia. The absence of a NG tube is not associated with reflux, probably since the gastroesophageal sphincter remains competent. NG tubes are not routinely necessary for cardiac surgery in patients without risk factors for GER, and increase reflux risk if managed without low-grade suction.
authors.affiliation: Department of Anaesthesia, Cardiothoracic Centre-Liverpool NHS Trust, England.
authors.forename: G N
authors.initials: GN
authors.lastname: Russell
authors.forename: P C
authors.initials: PC
authors.lastname: Yam
authors.forename: J
authors.initials: J
authors.lastname: Tran
authors.forename: P
authors.initials: P
authors.lastname: Innes
authors.forename: S D
authors.initials: SD
authors.lastname: Thomas
authors.forename: P D
authors.initials: PD
authors.lastname: Berry
authors.forename: M A
authors.initials: MA
authors.lastname: Fox
authors.forename: B M
authors.initials: BM
authors.lastname: Fabri
authors.forename: M
authors.initials: M
authors.lastname: Jackson
authors.forename: W I
authors.initials: WI
authors.lastname: Weir
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000965:Antimony; D001980:Bronchi; D006348:Cardiac Surgical Procedures / Q000009:adverse effects; D004322:Drainage; D004943:Esophagogastric Junction / Q000502:physiology; D005260:Female; D005547:Foreign Bodies / Q000209:etiology* / Q000503:physiopathology; D005764:Gastroesophageal Reflux / Q000209:etiology* / Q000503:physiopathology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007441:Intubation, Gastrointestinal / Q000295:instrumentation*; D007442:Intubation, Intratracheal; D008297:Male; D008875:Middle Aged; D011015:Pneumonia, Aspiration / Q000209:etiology; D012307:Risk Factors; D013396:Suction; D014132:Trachea
chemical_list: D000965:Antimony