title: Upper gastrointestinal endoscopy: a prospective randomized study comparing continuous supplemental oxygen via the nasal or oral route.
abstract: We have examined the efficacy of supplemental oxygen in preventing episodes of significant arterial desaturation (SpO2 less than 90%) during upper gastrointestinal endoscopy. We have compared the effects of 2 liters.min-1 of oxygen given orally via the bite-guard with the same flow rate via nasal cannulas and have also examined the effects of pre-oxygenation. Results of this study at a flow rate of 2 liters.min-1 have been compared with previously published results at a flow rate of 3 liters.min-1. Although in this study fewer episodes of desaturation were seen in the orally supplemented group compared with the nasal group, the difference observed was not statistically significant. Pre-oxygenation significantly reduced episodes of desaturation (SpO2 less than 90%, p less than 0.01) and prevented SpO2 falls below 85% in all patients studied. Supplemental oxygen given at a rate of 2 liters.min-1 was as effective as that given at a rate of 3 liters.min-1 in preventing significant desaturation, as previously defined, during the procedure. We therefore recommend the use of supplemental oxygen at a flow rate of 2 liters.min-1 in all high risk patients and conclude that the oral route has practical advantages and is at least as effective as nasal cannulas.
authors.affiliation: Department of Medicine, Ipswich Hospital, Suffolk, United Kingdom.
authors.forename: G D
authors.initials: GD
authors.lastname: Bell
authors.forename: A
authors.initials: A
authors.lastname: Quine
authors.forename: J H
authors.initials: JH
authors.lastname: Antrobus
authors.forename: A
authors.initials: A
authors.lastname: Morden
authors.forename: S M
authors.initials: SM
authors.lastname: Burridge
authors.forename: T J
authors.initials: TJ
authors.lastname: Coady
authors.forename: J
authors.initials: J
authors.lastname: Lee
mesh_terms: D016099:Endoscopy, Gastrointestinal; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000453:epidemiology / Q000517:prevention & control*; D008297:Male; D008874:Midazolam / Q000627:therapeutic use; D008875:Middle Aged; D010100:Oxygen / Q000008:administration & dosage* / Q000097:blood; D010102:Oxygen Inhalation Therapy; D011292:Premedication; D011446:Prospective Studies; D012189:Retrospective Studies
chemical_list: D008874:Midazolam; D010100:Oxygen