Pilot study of a newly developed expiratory positive airway pressure device

Background: Obstructive sleep apnea [OSA], a sleep-related breathing disorder that affects millions of people worldwide, is the result of partial or complete airflow obstruction that occurs during sleep. Oropharyngeal muscle relaxation during sleep can result in soft tissue collapse, with subsequent airflow impedance. During episodes of airflow obstruction, oxygen levels can drop precipitously, inducing a neurological arousal. Carbon dioxide build up interrupts sleep which triggers the respiratory drive for resumption of coordinated breathing. Complete wakefulness is rarely achieved during these episodes, but sleep quality is severely compromised. If left untreated, OSA may increase the risk of cardiovascular disease, arrhythmia, hypertension, stroke, diabetes, depression, obesity, and intellectual decline. Compliance with and tolerance of existing devices particularly the Continuous Positive Airway Pressure (CPAP) machine remains poor. Objectives: The present pilot study evaluates the utility of a newly developed mechanical nasal expiratory positive airway pressure [EPAP] device in OSA management. Method: A total of 19 adult subjects were recruited from two accredited sleep study centers based on a pre-existing, polysomnographic diagnosis of OSA with mild to moderate apnea-hypopnea index [AHI] scores. Sixteen subjects completed the study and underwent a standard polysomnography [PSG] procedure while wearing the nasal study device. The device consists of two cylindrical bodies with a ball-valve mechanism that creates airflow resistance during expiration, allowing for pneumatic splinting. Resulting data were compared to baseline PSG results, performed in the same sleep center as the study PSG. Results: Total apneas and hypopneas, respective indices for both, the cumulative apnea-hypopnea index, mean and minimum oxygen saturations during sleep, average and maximum heart rate during sleep, total desaturations and the desaturation index were evaluated and showed overall improvement. In the initial 6 patients, no significant improvement was observed in the overall indices; modifications were made to the device to minimize leak, and the subsequent 6 patients demonstrated a statistically significant improvement in obstructive indices and the minimum oxygen saturation achieved during sleep. Discussion: Thus far, 16 of 19 subjects have successfully completed a standard PSG with the nasal device. One subject aborted the study early due to emotional instability unrelated to the use of the device. Another subject with particularly small nasal passages reported that the device felt uncomfortably snug and aborted the study early as well. The remaining subjects tolerated the study well, without experiencing any appreciable side effects, and most patients have found the device to be comfortable. Ongoing improvements to the device have been implemented based on subject feedback in order to optimize comfort and efficacy of the device. Conclusion: This pilot study demonstrates the feasibility of using the EPAP device in patients with OSA. The device has been well tolerated by study subjects, has been reported to be comfortable, and standard sleep variables can be acquired with the device in place. Initial findings on the most updated model indicate improvement in AHI scores, oxygen saturation rates, and heart rate measured during sleep. *Correspondence to: Inderpal Randhawa, The Translational Pulmonary and Immunology Research Center (TPIRC) 701 E. 28th #419, Long Beach, CA 90806, USA, E-mail: docrandhawa@gmail.com Received: April 08, 2019; Accepted: April 23, 2019; Published: April 25, 2019 Abbreviations: OSA: Obstructive sleep apnea; CPAP: Continuous Positive Airway Pressure; AHI: Apnea-Hypopnea Index; EPAP: Expiratory Positive Airway Pressure; PSG: Polysomnography; AASM: American Academy of Sleep Medicine; LSAT: Lowest Oxygen Saturation; PEEP: Positive End-Expiratory Pressure; ODI: Oxygen Desaturation Index.