How can physicians best approach the challenge of distinguishing obstructive sleep apnea (OSA) from central sleep apnea (CSA) using purely endoscopic assessment during drug-induced sleep endoscopy (DISE)?
BOTTOM LINE
CSA can be easily mistaken for OSA; enhancing DISE with additional measurements enables sleep surgeons to correlate physiologic and anatomic assessment to distinguish between the two apneas.
BACKGROUND: Sleep apnea surgeons frequently employ DISE to visualize upper airway collapse in patients with OSA. Findings on DISE are used to guide surgical OSA management based on the site(s), severity, and pattern(s) of upper airway obstruction. Distinguishing obstructive from central events with purely endoscopic assessment during DISE can be challenging.
STUDY DESIGN: Case report
SETTING: Department of Otorhinolaryngology–Head and Neck Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Penn.
SYNOPSIS: A 58-year-old non-obese male with apnea symptoms and a history of cardiac conditions was diagnosed with moderate OSA via home sleep study. The claustrophobic patient was referred for alternatives to continuous positive airway pressure (CPAP), including hypoglossal nerve stimulation (HGNS). Researchers performed DISE with characterization of airway dynamics (DISE-CAD), providing real-time respiratory airflow and airway pressure signals alongside endoscopic image capture, enabling simultaneous anatomic and physiological assessment; CPAP was titrated during DISE-CAD to quantify upper airway collapsibility. Although the patient displayed anteroposterior collapse at the velum, tongue base, and epiglottis during baseline breathing at atmospheric nasal pressure under propofol, which would have rendered him suitable for HGNS, a waxing/waning Hunter-Cheyne-Stokes breathing (HCSB) pattern emerged during CPAP titration, with marked pharyngeal collapse during the hyperpneic phase. The subsequent polysomnogram showed severe predominant CSA. Following cardiopulmonary evaluation, the patient received phrenic nerve stimulation instead of HGNS. Authors state that, given cardiac conditions that predispose patients to CSA-HCSB, and the increased use of home sleep studies to diagnose OSA, physicians must remain attuned to the possibility of CSA masquerading as OSA.
CITATION: Cheong CS, Dedhia RC, Seay EG, et al. Enhanced drug-induced sleep endoscopy: Distinguishing central from obstructive apnea. Laryngoscope. 2023;133:706-708.