An Exploratory Study of Correlating Point Of Care Ultrasound (POCUS) Measures of Sleep Apnea With STOP-BANG Scoring and Apnea-Hypopnea Index (AHI)

Obstructive sleep apnea (OSA) is characterized by recurrent collapse of the pharyngeal airway during sleep, resulting in substantially reduced (hypopnea) or complete cessation (apnea) of airflow despite ongoing breathing efforts. OSA has long been recognized as a heterogeneous disorder with potentially multiple contributing pathophysiological causes but with significant impact to perioperative morbidity. Various OSA phenotypes exist but, the predominant feature is a narrow and collapsible upper airway anatomy and is an interplay between pharyngeal soft tissue, genioglossus muscle tone and the bony anatomy and accounts for up to two-thirds of the variation in the AHI. Identification of moderate-severe OSA is crucial to prevent potential life-threatening cardiopulmonary complications perioperatively.(1) However, a large proportion of patients with OSA remain undiagnosed at the time of surgery.(2) Current screening tools are mainly questionnaire based and are largely sensitive but not specific (3) resulting in many false positives, unnecessary increased resource utilization, cost burden, and legal implications. Gold standard laboratory polysomnography(PSG) study is expensive and not widely available. Point-of-care ultrasound (POCUS) is a readily available, portable, noninvasive tool that has been used for airway evaluation and may be useful for OSA screening.(4-8) Study investigators want to evaluate the various POCUS measures of OSA in the perioperative population and correlate these measurements with the PSG based severity of OSA (based on apnea-hypopnea index -AHI) to find out the best measure or a combination of measures to diagnose the incidence and severity of OSA.