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Figure 2 | Critical Care

Figure 2

From: High flow biphasic positive airway pressure by helmet – effects on pressurization, tidal volume, carbon dioxide accumulation and noise exposure

Figure 2

Helmet flow (l/min), helmet pressure (Paw) and muscle pressure (Pmus) tracings during helmet non-invasive ventilation. Td (Trigger delay) indicates the time between the onset of Pmus (T0) and the onset of ventilator assistance. Pressure time products (PTP) were calculated from the time between the onset of inspiration and the pressure below PEEP (PTPPEEP), the pressure above positive end-expiratory end pressure (PEEP) from onset to the end of inspiration (PTPinsp) as well as for the expiratory phase (PTPexp). Note: As the lower pressure represents the target pressure, PTPexp was calculated as the pressure time product beyond PEEP/P1 in order to calculate the extra pressure imposed due to poor synchronization. Tracings were measured during pressure support ventilation (normal lung, respiratory rate 30 bpm, Δ pressure 15 cmH2O).

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Critical Care

ISSN: 1364-8535