Fig. 1From: Intrathoracic pressure regulation therapy applied to ventilated patients for treatment of compromised cerebral perfusion from brain injuryActive intrathoracic pressure regulation device (CirQlator™, ZOLL) used in the study to provide active intrathoracic pressure regulation therapy. The device is connected between a ventilation source and the patient’s airway circuit and the vacuum port tubing is connected to a regulated vacuum source. aIPR active intrathoracic pressure regulation, ETCO 2 end-tidal carbon dioxideBack to article page