EFFECT OF SUPPLEMENTAL OXYGEN ON CARDIOPULMONARY CHANGES DURING GASTROINTESTINAL ENDOSCOPY

This prospective study evaluated supplemental oxygen as an effective m eans of preventing hypoxemia and electrocardiographic changes in sedat ed patients undergoing endoscopic procedures. Ninety-five patients wit h documented ischemic heart disease and 106 patients without heart or lung disease were studied. Patients within each group received either supplemental oxygen (2 L/minute) via nasal cannula or room air. Hypoxe mia (oxygen saturation below 90%) and ST-segment deviations occurred i n cardiac and control groups. The combination of midazolam and meperid ine significantly increased the risk far hypoxemia as compared to mida zolam alone (44% versus 8%). Supplemental oxygen significantly decreas ed, but did not entirely prevent, hypoxemia in cardiac and control gro ups. The incidence of ST-segment deviation in cardiac patients who wer e hypoxic was significantly lower in the group receiving oxygen (p = . 0015). Supplemental oxygen did not affect the incidence of arrhythmias . Prophylactic supplemental oxygen should be administered to patients with ischemic heart disease who undergo conscious sedation for upper a nd lower gastrointestinal endoscopic procedures.