1. The third breath has a negative deflection (ie, below PEEP) at the end of the mechanical breath (arrow A) associated with a flow increase (arrow B), indicating that the patient has not ceased to inhale when ventilator-assisted inspiration has ceased.
The third breath has a negative deflection (ie, below PEEP) at the end of the mechanical breath (arrow A) associated with a flow increase (arrow B), indicating that the patient has not ceased to inhale when ventilator-assisted inspiration has ceased. Note the plateau in the volume-time waveform (arrow C) demonstrating that the patient is keeping the volume in their thorax and is not exhaling. This patient is being ventilated with 2 types of breaths. The mandatory synchronized intermittent mandatory ventilation breaths are volume-controlled (600 mL) and flow-targeted (50 L/min). The non-mandatory breaths are pressure-support breaths (15 cm H2O) with cycling sensitivity of 25% (graphically the flow ceases at a quarter of peak flow). The PEEP is 5 cm H2O, giving a peak pressure of 20 cm H2O on the pressure-support breaths.
Marjolein de Wit Respir Care 2011;56:61-72
(c) 2012 by Daedalus Enterprises, Inc.