Effect of nasal valve dilation on effective CPAP level in obstructive sleep apnea

Abstract

Nasal problems are frequent at high continuous positive airway pressure (CPAP). We hypothesized that a reduction of the nasal resistance reduces CPAP and investigated the effect of a nasal valve dilator (Nozovent^®) on CPAP in patients with obstructive sleep apnea. In a randomized cross-over design Nozovent^® was inserted in 38 patients during one of two nights using AutoSet T^®. CPAP differences >1 cm H₂O were considered as clinically relevant. With Nozovent^® the median CPAP pressure was reduced from 8.6 cm H₂O to 8.0 H₂O (P=0.023) in all patients, but the number of patients with a reduction of CPAP by 1 cm H₂O was not significant. The median CPAP level among 20 patients requiring a CPAP level of above 9 cm H₂O was reduced from 10.3 to 9.1 cm H₂O, P<0.05. A clinical improvement with Nozovent^® was seen in 10 of 20 patients requiring a pressure of above 9 cm H₂O compared with 4 of 18 patients who needed lower pressures, P=0.025. Nozovent^® reduces the CPAP level 1 cm H₂O in 50% of patients requiring a high pressure (>9 cm H₂O). Future studies should identify possible patients benefiting from a nasal dilator during CPAP therapy.