0769 Comparison of Expiratory Pressures Generated by ULTepap, Provent, Bongo Rx, and Theravent EPAP Devices: A Laboratory Bench Testing

Abstract

Abstract Introduction Expiratory positive airway pressure (EPAP) has been a treatment option for patients with obstructive sleep apnea (OSA). Among devices like Provent, Theravent, and Bongo, ULTepap is a new FDA-cleared EPAP device that seals around the nares with a nasal pillow interface. Comparisons among the expiratory pressures that these devices might generate are not available. Research Question: Are expiratory threshold therapy devices equivalent in generating backpressure in an expiratory direction? Methods A test rig was designed and fabricated to test the pressures generated by ULTepap, Provent, Theravent, and Bongo Rx. Airflow was generated by a linear actuator-driven piston in a syringe, and a range of flow rates was provided by varying the voltage input to the actuator. The resulting pressures were measured in an expiratory and inspiratory direction. Results The backpressures produced by ULTepap and Provent were comparable at flow rates of 99/142/212 ml/sec (average 3.5/7.5/13.8 cmH2O for ULTepap vs 4.5/8.5/14.5 cmH2O for Provent, p=0.7918). Bongo Rx and Theravent devices produced substantially lower backpressures than ULTepap devices (average 0.8/1.8/3.5 cmH2O for Bongo Rx and 0.9/2.2/5.3 cmH2O for Theravent at flow rates of 99/142/212 ml/sec, p=0.0138 and 0.0404, respectively). In comparison, all four devices presented very low inspiratory flow resistance, with all generating 0.5 cmH2O or less at all flow rates. Conclusion Not all FDA-cleared EPAP devices produce similar expiratory pressure profiles. ULTepap generated backpressures closest to that of Provent. Clinical trials comparing the efficacy, tolerance, and role of these EPAP devices in patients with OSA are warranted. Support (If Any)