Performances of cpap devices with an oronasal mask

BACKGROUND: The aim of this bench study was to investigate the performances of 8 devices for noninvasive CPAP. METHODS: Eight devices for noninvasive CPAP with an orofacial mask were studied: Ventumask, Ventumask 30, EasyVent, EasyVent Emergency, Compact Model II, Flowone, Superflow, Boussignac CPAP valve. Each device was tested at oxygen input flows from 5 to 20 L/min, and the output gas flow was measured in static conditions. Each device was evaluated during a eupneic and a tachypneic simulated breathing test. RESULTS: The gas output flow generated by each device increased with higher oxygen input flow; EasyVent and Flowone produced the highest output flow (P < .001). At the simulated eupneic breathing test, Superflow and EasyVent showed a more stable pressure swing at different PEEP levels, whereas the other masks had a greater swing, between 10 and 15 cm H2O PEEP (P = .002 for all pairwise comparisons). During the tachypneic breathing test, the pressure swing was stable with Flowone and EasyVent (P = .055), whereas it had increased with other masks (P = .002 for all pairwise comparisons). CONCLUSIONS: We found a significant variation in the performances of the 8 CPAP devices examined in this study. The technical characteristics and limitations of different CPAP devices should be considered when using in patients with hypoxemic acute respiratory failure. Key words: CPAP; mechanical ventilation; respiratory failure; hypoxemia; orofacial mask; effectiveness; efficacy.