Evaluation of auto bi-level algorithm to treat pressure intolerance in obstructive sleep apnea
Swedish Medical Center, 550 17th Avenue, Suite A20, Seattle, WA, 98122, USA.
The objective of this study was to evaluate whether a new auto-adjusting bi-level algorithm was comparable to a standard method for prescribing bi-level therapy.
This study was a prospective randomized, double-blinded crossover evaluation of the equivalency of the auto-adjusting bi-level mode (VAuto) compared to standard bi-level mode, using a pre-determined difference in Apnea-Hypopnea Index (AHI) of five events per hour. Data were obtained during sleep studies performed on two separate nights. Twenty-two subjects met the entry criteria and were enrolled in the study at four investigational sites in the USA.
Mean AHI for the auto-adjusting bi-level mode was 6.2 +/- 5.4 events per hour and for the standard bi-level mode 8.3 +/- 5.8 events per hour. The AHI for the two modes were clinically equivalent. The difference in median pressure between these two modes was -3.8 cm H(2)O +/- 3.6 (p = 0.0008) in favor of the auto-adjusting bi-level mode. In addition, the maximum pressure was significantly higher in the auto-adjusting bi-level mode (16.0 cm H(2)O vs. 14.1 cm H(2)O, p = 0.02).
Our results demonstrated that the auto-adjusting bi-level mode normalized AHI comparable to the standard bi-level mode. The results of this study have several significant implications for the clinical management of sleep apnea. Obstructive sleep apnea (OSA) is a common condition and is associated with untoward complications. Non-compliance with positive airway pressure (PAP) limits the efficacy of the PAP therapy. The auto-adjusting bi-level mode provides a potentially reliable alternative for sleep clinicians faced with prescribing bi-level PAP for non-compliant patients. This study documents that this type of auto-adjusting device provides effective treatment of OSA.
Sleep Breath. 2010 Jul 6