The effect of supplemental oxygen in sedated and unsedated patients undergoing upper gastrointestinal endoscopy

A total of 212 patients undergoing elective upper gastrointestinal endoscopy were prospectively studied. They were randomly assigned to one of four treatment groups: (I) sedation with no supplemental oxygen; (II) no sedation and no oxygen supplementation; (III) sedation and supplemental oxygen; and (IV) no sedation but supplemental oxygen. Oxygen desaturation occurred in all the groups except group IV and was worsened by sedation. Supplemental oxygen corrected the desaturation in the sedated patients and minimized the associated haemodynamic changes. The duration of the endoscopy procedure was shortest in patients who were sedated and given supplemental oxygen. It can be concluded that during conscious sedation for upper gastro-intestinal endoscopy, supplemental oxygen should be given and continued during the postendoscopy period to prevent oxygen desaturation.