title: A randomized crossover trial of the effect of a novel method of pressure control (SensAwake) in automatic continuous positive airway pressure therapy to treat sleep disordered breathing.
abstract: OBJECTIVE
  To study the acute effect of the new SensAwake CPAP modality (reducing pressure on awakenings) on wake after sleep onset (WASO) and other polysomnographic measures in patients with obstructive sleep apnea (OSA).
  
  
  METHODS
  Randomized crossover trial comparing an automatic continuous positive airway pressure device (AutoCPAP) with and without SensAwake on sleep architecture. CPAP naive patients received each therapy for a single night in the laboratory with at least 1-week washout. Both patients' and technicians' subjective satisfaction was assessed. Pressure data measured and stored by the AutoCPAP device were also analyzed.
  
  
  RESULTS
  OSA was controlled adequately by both modes (SensAwake ON apnea hypopnea index ± SD, AHI = 5.3 ± 5.6/h vs. SensAwake OFF = 5.4 ± 5.8, p = 0.9) in the 42 patients who completed the protocol. Mean and 90% pressures were significantly lower with SensAwake (mean ON = 6.9 ± 1.9 vs. OFF = 7.7 ± 2.5 cm H(2)O, p < 0.05; 90% pressure ON = 9.6 ± 2.7 vs. OFF = 10.6 ± 2.7 cm H(2)O, p < 0.02). SensAwake did not improve WASO (ON = 74 ± 54 min vs. OFF = 78 ± 51 min, p = 0.6). There were no differences in other sleep architecture measures or patient satisfaction between the 2 modalities. AutoCPAP-measured AHI closely approximated PSG-derived (ROC AUC = 0.81 [95% CI 0.71-0.92], p = 0.0001).
  
  
  CONCLUSIONS
  SensAwake provides similar control of the AHI to the standard AutoCPAP mode but does so at lower mean and 90% pressures. However, no measure of sleep architecture was significantly improved by the SensAwake mode during this initial acute exposure. The internal AutoCPAP AHI detection and calculation was similar to PSG-derived AHI measures. Longer term studies are needed to evaluate any long-term influence of SensAwake on WASO.
authors.affiliation: Woolcock Institute of Medical Research, Sydney Medical School, University of Sydney, Australia. gdungan@med.usyd.edu.au
authors.forename: George C
authors.initials: GC
authors.lastname: Dungan
authors.forename: Nathaniel S
authors.initials: NS
authors.lastname: Marshall
authors.forename: Camilla M
authors.initials: CM
authors.lastname: Hoyos
authors.forename: Brendon J
authors.initials: BJ
authors.lastname: Yee
authors.forename: Ronald R
authors.initials: RR
authors.lastname: Grunstein
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D045422:Continuous Positive Airway Pressure / Q000295:instrumentation* / Q000379:methods*; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography; D012891:Sleep Apnea Syndromes / Q000628:therapy*; D016896:Treatment Outcome; D055815:Young Adult