SHORT PAPER Polysomnography with an epiglottic pressure catheter does not alter obstructive sleep apnea severity or sleep efficiency Sophie G. Carter 1 | Jayne C. Carberry 1 | Ronald R. Grunstein 2 | Danny J. Eckert 1 1 Neuroscience Research Australia (NeuRA), Sydney, NSW, Australia 2 Woolcock Institute of Medical Research, Sydney, NSW, Australia Correspondence Sophie G. Carter, Neuroscience Research Australia (NeuRA), Randwick, NSW, Australia. Email: s.carter@neura.edu.au Funding information This study was funded by a National Health and Medical Research Council (NHMRC) of Australia project grant (1042493) and NeuroSleep, a NHMRC Centre for Research Excellence (1060992). DJE is supported by a NHMRC Senior Research Fellowship (1116942). RRG is supported by a NHMRC Senior Principal Research Fellowship (1106974). JCC is supported by a NeuroSleep Fellowship (1060992). Abstract Pharyngeal and oesophageal manometry is used clinically and in research to quantify respiratory effort, upper‐airway mechanics and the pathophysiological contributors to obstructive sleep apnea. However, the effects of this equipment on respiratory events and sleep in obstructive sleep apnea are unclear. As part of a clinical trial (ANZCTRN12613001106729), data from 28 participants who successfully com- pleted a physiology night with an epiglottic catheter and nasal mask followed by a standard in‐laboratory polysomnography were compared. The apnea–hypopnea index was not different during the physiology night versus standard polysomnogra- phy (22 ± 14 versus 23 ± 13 events per hr, p = 0.71). Key sleep parameters were also not different compared between conditions, including sleep efficiency (79 ± 13 ver- sus 81 ± 11%, p = 0.31) and the arousal index (26 ± 11 versus 27 ± 11 arousals per hr, p = 0.83). There were, however, sleep stage distribution changes between nights with less N3 and rapid eye movement sleep and more N1 on the physiology night, with no difference in N2 (53 ± 15 versus 48 ± 9, p = 0.08). However, these changes did not increase next‐day sleepiness. These findings indicate that while minor sleep stage distribution changes do occur towards lighter sleep, epiglottic manometry does not alter obstructive sleep apnea severity or sleep efficiency. Thus, epiglottic manometry can be used clinically and to collect detailed physiological information for research without major sleep disruption. KEYWORDS arousal threshold, pharyngeal manometry, respiratory effort, sleep‐disordered breathing, upper‐ airway physiology 1 | INTRODUCTION There are anatomical and non‐anatomical contributors to obstructive sleep apnea (OSA) pathophysiology (Eckert, 2018). Manometry is used to define key contributors to OSA, such as upper‐airway (UA) collapsibility (Pcrit), the amount of negative airway pressure gener- ated during events (i.e. respiratory effort) and the respiratory arousal threshold (nadir airway pressure just prior to arousal during a respi- ratory event; Eckert, 2018). The gold‐standard approach to quantify these contributors involves insertion of a thin catheter through the nostril to a level below the site/s of airway collapse (i.e. epiglottis or gastro‐oesophageal junction; Berry, Mcnellis, Kouchi, & Light, 1997; Eckert, White, Jordan, Malhotra, & Wellman, 2013). Although cathe- ters are sometimes used clinically to inform certain sleep‐disordered breathing diagnoses (Guilleminault, Li, Chen, & Poyares, 2002) and commonly for physiology research, their effects on key sleep param- eters in OSA remains unclear. A recent study found that an oesophageal catheter (Poes) does not affect UA collapsibility in anaesthetised people with and without OSA (Maddison et al., 2015). Previous studies indicate small but con- sistent changes in sleep architecture with various types of Poes catheters (Chervin & Aldrich, 1997; Hutter, Holland, & Ashtyani, Received: 1 July 2018 | Revised: 17 August 2018 | Accepted: 18 August 2018 DOI: 10.1111/jsr.12773 J Sleep Res. 2018;e12773. https://doi.org/10.1111/jsr.12773 wileyonlinelibrary.com/journal/jsr © 2018 European Sleep Research Society | 1 of 5