Effect of different ventilator respiratory settings and respiratory rate on mean tidal volume delivered to the helmet (VTinsp Helmet) and to the Active Simulator Lung (VTinsp Lung) with HF-BiPAP, BiVent, and PSV ventilation. Measurements were made in normal (compliance 90 ml/cmH2O, resistance 3 cmH2O/l/s), restrictive (compliance 30 ml/cmH2O, resistance 3 cmH2O/l/s), and obstructive lung conditions (compliance 90 ml/cmH2O, resistance 15 cmH2O/l/s) at low (2.5 cmH2O) and high inspiratory efforts (10 cmH2O) at a respiratory rate of 15 and 30 breaths per minute. Grey columns = inspiratory VT to the Active Lung Simulator (VTinsp Lung); white columns = inspiratory VT to the Helmet (VTinsp helmet). BiVent = time-cycled pressure controlled switching between two continuous positive airway pressure levels; HF-BiPAP = high flow biphasic positive airway pressure; PSV = pressure support ventilation.
Moerer et al. Critical Care 2009 13:R85 doi:10.1186/cc7907