High-Flow Nasal Cannula in Subjects Undergoing Endoscopy With Intravenous Sedation

Background: High-flow nasal cannula (HFNC) is a noninvasive oxygenation method that delivers humidified and heated oxygen mixtures at high flows while generating PEEP. Therefore, its use during endoscopic procedures with intravenous deep sedation may help maintain airway patency and oxygenation. This study aims to compare the incidence of reductions in oxygen saturation in subjects receiving HFNC at different flows with that in subjects receiving conventional oxygen therapy during endoscopic retrograde cholangiopancreatography (ERCP). Secondary outcomes include the lowest observed S pO 2 , snoring scores, and satisfaction levels of both subjects and gastroenterologists. Methods: This single-center randomized trial included 60 subjects undergoing ERCP with deep intravenous sedation in the left lateral decubitus position and randomized into 1 of 3 groups Group 0 received 5 L/min of oxygen via nasal cannula, resulting in an F IO 2 of ∼0.40; Group 1 received HFNC at a flow of 15 L/min and an F IO 2 of 0.40; and Group 2 received HFNC at a flow of 60 L/min and an F IO 2 of 0.40. S pO 2 values were obtained at each 1-min interval from the beginning until the end of anesthesia. Results: The incidence of falls in oxygen saturation and the lowest S pO 2 during the procedure were not different among the 3 groups. However, the average S pO 2 throughout the procedure was significantly greater in Group 1 (99.2 ± 0.2%) and Group 2 (99.6 ± 0.3%) than in Group 0 (97.4 ± 0.3%, both P < .001), with no difference between Groups 1 and 2 ( P = .26). No significant differences were observed in the duration of procedures, snoring classification scores, and gastroenterologist and subject satisfaction levels among the 3 groups. Conclusions: In low-risk subjects undergoing ERCP, oxygen therapy with HFNC with an F IO 2 of 0.40 did not reduce the rate of oxygen saturation reductions or the lowest measured oxygen saturation compared with standard low-flow oxygen cannula at 5 L/min.