Fig. 7From: Heat and moisture exchangers (HMEs) and heated humidifiers (HHs) in adult critically ill patients: a systematic review, meta-analysis and meta-regression of randomized controlled trialsMeta-regression on artificial airway occlusion including duration of mechanical ventilation (β = 2.637; p = 0.054) and pneumonia (β = 1.794; p = 0.012) as covariate. HME heat and moisture exchanger, HH heated humidifierBack to article page