Nasopharyngeal airway for oxygenation and sevoflurane inhalation during endoscopic retrograde cholangiopancreatography in patients with obstructive sleep apnea

Abstract

Objectives The aim of this study was to evaluate applicability of nasopharyngeal airway (NPA) for the maintenance of patients’ oxygenation during sevoflurane inhalational anesthesia through NPA against propofol infusion and traditional endotracheal intubation (ETT). Patients and methods The study included 111 patients with obstructive sleep apnea (OSA). Risk of OSA was evaluated preoperatively using the STOP-BANG Questionnaire. Patients were randomly allocated into three groups: group E received propofol infusion (50–150 μg/kg/min) with atracurium (0.3 mg/kg), group S received sevoflurane inhalation (1 MAC) through NPA, and group P was maintained on propofol infusion (50–150 μg/kg/min). The frequency and severity of hypoxemic attacks and the requirement for ETT in groups S and P were compared. Results Sixty-four patients (57.7%) had mild, whereas and 47 patients (42.3%) had an iintermediate OSA grade on STOP-BANG score. At the end of endoscopic retrograde cholangiopancreatography, heart rate, mean arterial pressure, and mean PSaO2 measures were found significantly lower in all patients compared with baseline estimates. Concentration of PSaO2 was significantly lower in group P compared with groups E and S. The frequency of hypoxemic attacks was nonsignificantly higher with NPA compared with ETT and only five patients required ETT. The frequency of procedural sedation-related adverse events was nonsignificantly lower with NPA compared with ETT (27 vs. 32.4%). The frequency till full recovery was significantly longer in group E compared with groups S and P, with a significant difference in favor of group S. Patients’ satisfaction scorings were significantly higher in groups S and P compared with group E. Endoscopist satisfaction scorings were significantly higher in groups S and E compared with group P. Conclusion NPA could be applied for the oxygenation of patients undergoing endoscopic retrograde cholangiopancreatography, even on those having OSA with an acceptable frequency of hypoxic attacks and conversion rate to ETT. Sevoflurane sedation was an advantageous alternative to propofol sedation for an early, easy recovery with less adverse events.