Combined Negative- and Positive-Pressure Ventilation for the Treatment of ARDS

Figure 2

Course of gas exchange and ventilatory pressures. After three days of noninvasive positive-pressure ventilation, the patient was intubated and ventilated in a pressure-controlled mode. Three days later, negative-pressure ventilation was commenced in combination with conventional pressure support (gray columns). In both ventilatory modes, inspiratory pressures are shown as red and expiratory pressures as green lines. Ventilatory pressures represent inspiratory plateau pressures and positive end-expiratory pressures (PEEP) during conventional positive-pressure ventilation and maximum or minimum chamber pressures during negative-pressure ventilation.