O051 Comparison of standard CPAP therapy and the RACer airway device for the treatment of obstructive sleep apnoea: A randomised clinical trial

The nasal cycle is a normal ultradian physiological phenomenon where each nasal airway alternates conducting dominance. The nasal cycle occurs in obstructive sleep apnoea (OSA). Rest-Activity-Cycler positive airway pressure (RACer-PAP) is a novel treatment aiming to maintain the innate nasal cycle. METHODS: PAP naïve OSA patients were randomly assigned in a crossover design to 4 weeks RACer or control humidified CPAP (3 day wash-out). Treatment pressure determined by in-lab Auto-titration. Adherence, Epworth Sleepiness Score (ESS), quality of life (SF 36), nasal symptoms, side effects, sleep quality compared by SAS 9.4 or Likert scale. RESULTS: 40 subjects (of 44 recruited) (29 M, 11 F) with a mean BMI 37.7kg/m2 aged 45 yrs (range 22-70 yrs) with severe OSA (mean AHI 56.4/ hr), ESS 13.6 (range 3-21) completed the study. Ethnicity included Maori (17 %), NZ European (67%), and Pacific (12.5%). The prescribed mean pressure 12.2 (range 8-18 cmH20). Adherence was greater in the humidified CPAP control than RACer- PAP arm (4:57h/night verse 4:14h/night p < 0.01). Both devices similarly improved subjective sleepiness, quality of life and adverse upper airway symptoms. Humidified CPAP improved to a greater extent nasal symptom scores (baseline – final: control CPAP 2.8 vs. RACer 2.3, p = 0.03), sleep quality and was preferred (55% vrs 22 %). CONCLUSION: RACer PAP improved OSA symptoms and quality of life but adherence was lower and nasal symptoms more common. This could be explained by not using humidification, technical issues with prototype machine or the use of set nasal cycle length.