The Repeatability of Pharyngeal Opening Pressure Under Drug‐Induced Sleep Endoscopy

Abstract Objective Pharyngeal opening pressure (PhOP) is a measure of upper airway collapsibility that can be obtained during drug‐induced sleep endoscopy (DISE) using a continuous positive airway pressure (CPAP) titration. However, the stability of PhOP over the course of sedation during DISE remains unclear. This study aims to compare repeat measures of PhOP over the course of DISE. Study Design Single arm prospective study. Setting Single tertiary care institution. Methods Patients had 2 CPAP titrations while undergoing DISE. Collected data included patient demographics, PhOP, patient sedation index (PSI), and duration of and between CPAP titrations. t Tests, test‐retest coefficient analysis, and repeated measures correlation were performed. Results Twenty‐five patients completed the study between 2022 and 2023 with 22 patients having sedation depth (PSI) recording. Most were male (76%), obese (average body mass index: 30.24 kg/m 2 ), with severe obstructive sleep apnea (average apnea‐hypopnea index: 39.8 events/hr). Test‐retest analysis showed good‐excellent correlation between PhOP values (intraclass correlation coefficient = 0.892, P < .0001, n = 25). Average time between CPAP titrations was 15 minutes to 6 seconds. Over that time, PhOP increased by an average of 0.72 cmH 2 O ( P = .06, n = 25) and PSI decreased by 9.5 units ( P = .01, n = 22). Repeated measures correlation showed a weak negative correlation between PhOP and PSI ( r = −.45, P = .03, n = 22). Conclusion The results showed repeatability of PhOP values over the course of DISE. When adjusted for sedation depth (PSI), deeper sedation was weakly associated with greater PHOP. However, the magnitude of this change was small and we conclude that PhOP remains relatively stable over the course of DISE (Effects of Lung Volume on Upper Airway Patency During DISE DISE‐Pulm, NCT05350332, clinicaltrials.gov ).