Head and thorax elevation during active compression decompression cardiopulmonary resuscitation with an impedance threshold device improves cerebral perfusion in a swine model of prolonged cardiac arrest

Abstract

Aim: To compare brain blood flow between the head up (HUP) and supine (SUP) body positions during prolonged cardiopulmonary resuscitation (CPR), using active compression-decompression (ACD) CPR and an impedance threshold device (ITD) in a swine model of cardiac arrest. Methods: After 8 minutes of untreated ventricular fibrillation (VF), followed by 2 minutes of ACD-CPR+ITD in the SUP position, pigs were randomized to 18 minutes of ACD-CPR+ITD in either 30o HUP or SUP position. Microspheres were injected before VF, and then 5 and 15 minutes after study start. Results: Brain Blood flow (ml/min/g, mean ± SD) after 15 minutes of CPR was 0.42±0.05 for HUP (n=8) and 0.21±0.04 for SUP (n=10), (p<0.01). The HUP group also had lower intracranial pressures and higher cerebral perfusion pressures. Conclusions: Brain blood flow in the HUP position was higher in than the SUP position. This provides pre-clinical support to proceed with a clinical evaluation of head up CPR in humans.