Influence of total face, facial and nasal masks on short-term adverse effects during noninvasive ventilation.

OBJECTIVE Failure of noninvasive ventilation (NIV) has been associated with short-term adverse effects related to the use of masks. The aim of this study was to compare the incidence, type and intensity of adverse effects, as well as the comfort, of total face masks (TFMs), facial masks (FMs) and nasal masks (NMs) during NIV. METHODS This was a randomized crossover trial involving 24 healthy volunteers submitted to six sessions of NIV in bilevel positive airway pressure mode using the TFM, FM and NM masks at low and moderate-to-high pressure levels. A written questionnaire was applied in order to evaluate eleven specific adverse effects related to the use of the masks. Comfort was assessed using a visual analog scale. The CO2 exhaled into the ventilator circuit was measured between the mask and the exhalation port. RESULTS The performance of the TFM was similar to that of the NM and FM in terms of comfort scores. Higher pressure levels reduced comfort and increased adverse effects, regardless of the mask type. When the TFM was used, there were fewer air leaks and less pain at the nose bridge, although there was greater oronasal dryness and claustrophobia. Air leaks were most pronounced when the FM was used. The partial pressure of exhaled CO2 entering the ventilator circuit was zero for the TFM. CONCLUSIONS The short-term adverse effects caused by NIV interfaces are related to mask type and pressure settings. The TFM is a reliable alternative to the NM and FM. Rebreathing of CO2 from the circuit is less likely to occur when a TFM is used.