Use of heated humidification during nasal CPAP titration in obstructive sleep apnoea

Nasal symptoms associated with the use of nasal continuous positive airway pressure (nCPAP) in obstructive sleep apnoea (OSA) can adversely impact on patients' tolerance, acceptance and adherence to nCPAP therapy. Regular use of heated humidification is effective in alleviating these symptoms and improve patient comfort. In a randomised, parallel, double-blinded, controlled study, the present authors examined the use of heated humidification during a single night laboratory nCPAP titration in untreated OSA patients and its effect on nasal symptoms, nasal airway resistance (NAR), effective pressure and treatment tolerability and acceptance. Baseline characteristics of subjects (n570) receiving placebo and humidification were (mean¡SEM): age 51.2¡2.2 versus 50.6¡1.6 yrs; body mass index 33.6¡0.9 versus 35.2¡0.9 kg?m-2; Epworth Sleepiness Scale 10.8¡1.0 versus 11.3¡0.7; and apnoea-hypopnoea index 43.5¡4.6 versus 44.4¡4.1 events?h-1. Total inspiratory NAR, before (0.36¡0.09 (placebo) versus 0.33¡0.09 kPa?L-1?s-1) and after nCPAP (0.47¡0.11 versus 0.29¡0.04 kPa?L-1?s-1) were not significantly different between the groups. No difference was found in the frequency and severity of nasopharyngeal symptoms, therapeutic pressure and subjective response to nCPAP. In conclusion, heated humidification during the initial nasal continuous positive airway pressure titration offers no additional benefit in nasal physiology, symptoms or subjective response to nasal continuous positive airway pressure, and, therefore, should not be routinely recommended.