title: Equivalence of nasal and oronasal masks during initial CPAP titration for obstructive sleep apnea syndrome.
abstract: OBJECTIVE
  Continuous positive airway pressure (CPAP) titration studies are commonly performed using a nasal mask but some patients may prefer a full-face or oronasal mask. There is little evidence regarding the equivalence of different mask interfaces used to initiate treatment. We hypothesized that oronasal breathing when using an oronasal mask increases upper airway collapsibility and that a higher pressure may be required to maintain airway patency. We also assessed patient preferences for the 2 mask interfaces.
  
  
  METHODS
  Prospective, randomized, cross-over design with 2 consecutive CPAP titration nights.
  
  
  METHODS
  Accredited laboratory in a university hospital.
  
  
  METHODS
  Twenty-four treatment-naive subjects with obstructive sleep apnea syndrome and respiratory disturbance index of greater than 15 events per hour.
  
  
  METHODS
  CPAP titration was performed using an auto-titrating machine with randomization to a nasal or oronasal mask, followed by a second titration night using the alternate mask style.
  
  
  RESULTS
  There was no significant difference in the mean pressures determined between nasal and oronasal masks, although 43% of subjects had nasal-to-oronasal mask-pressure differences of 2 cm H(2)O or more. Residual respiratory events, arousals, and measured leak were all greater with the oronasal mask. Seventy-nine percent of subjects preferred the nasal mask.
  
  
  CONCLUSIONS
  Patients with obstructive sleep apnea syndrome can generally switch between nasal and oronasal masks without changing machine pressure, although there are individual differences that may be clinically significant. Measured leak is greater with the oronasal mask. Most patients with obstructive sleep apnea syndrome prefer a nasal mask as the interface for initiation of CPAP.
  
  
  BACKGROUND
  Australian New Zealand Clinical Trials Registry (ANZCTR). ACTRN: ACTRN12611000243910. URL: http://www.ANZCTR.org.au/ACTRN12611000243910.aspx
authors: Ludwig Engel Centre for Respiratory Research, Westmead Millennium Institute, Westmead, NSW, Australia.
authors: Ming
authors: M
authors: Teo
authors: Terence
authors: T
authors: Amis
authors: Sharon
authors: S
authors: Lee
authors: Karina
authors: K
authors: Falland
authors: Stephen
authors: S
authors: Lambert
authors: John
authors: J
authors: Wheatley
mesh_terms: D000328:Adult; D045422:Continuous Positive Airway Pressure / Q000295:instrumentation*; D018592:Cross-Over Studies; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008397:Masks; D008875:Middle Aged; D057240:Patient Preference; D011446:Prospective Studies; D012119:Respiration; D020181:Sleep Apnea, Obstructive / Q000628:therapy*