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The impact of V̇-Com on chinstrap usage and study completion rates during CPAP titration
Ludovico Messineo1, Carmen Keasling2, Bryan Hughes2
1Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham & Women's Hospital & Harvard Medical School, Boston, Massachusetts.
Study Objectives:
Mouth leak during continuous positive airway pressure (CPAP) therapy is a common barrier to tolerability and adherence and is often managed with chinstraps. We investigated whether V̇-Com, a device that reduces inspiratory pressure by adding noncompensated resistance into the CPAP circuit, could lower the chinstrap usage rate during in-laboratory titration. Additionally, we tested the effect of V̇-Com on study abortion rate due to CPAP intolerance.
Methods:
We conducted a retrospective study of in-laboratory CPAP titrations performed at a multisite sleep center. Mouth leak was identified based on ventilator-reported leak (> 30 L/min), visual observation of mouth opening, or characteristic alterations in the flow signal. V̇-Com was added as a first-line intervention when mouth leak was detected. If V̇-Com proved ineffective, it was removed, and a chinstrap was utilized. Similarly, V̇-Com was used in the attempt to salvage studies that were otherwise going to be aborted due to positive airway pressure intolerance.
Results:
Among 1,632 titrations, 190 patients (12%) experienced mouth leak and 46 individuals requested to abort their titration due to positive airway pressure intolerance (3%). V̇-Com reduced the chinstrap usage rate by 68% and the study abortion rate by 91%. In sensitivity analysis modeling hypothetical placebo response rates, the number needed to treat to avoid chinstrap use in 1 additional participant remained as low as 5, even under conservative assumptions.
Conclusions:
V̇-Com was associated with reduced chinstrap use and fewer aborted studies during CPAP titration. This suggests that V̇-Com may serve as a useful tool to improve pressure tolerance and leak management.
Citation:
Messineo L, Keasling C, Hughes B, et al. The impact of V̇-Com on chinstrap usage and study completion rates during CPAP titration. J Clin Sleep Med. 2025;21(12):2121-2127.
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