Augmentation of tissue perfusion by a novel compression device increases neurologically intact survival in a porcine model of prolonged cardiac arrest

Objective: This study was performed to determine the potential efficacy of an automated device with a load-distributing band (AutoPutse (TM), Revivant Corporation), in improving neurologically intact survival after cardiac arrest. Design: Randomized, controlled trial. Setting: University animal laboratory. Subjects: Forty-four swine (18-23 kg). Interventions: Eight minutes after induction of untreated ventricular fibrillation, pigs were randomized to AutoPulse-CPR (A-CPR, n=22), conventional cardiopulmonary resuscitation (CPR) with 20% anterior-posterior chest displacement (CCPR20, n = 10) or 30% chest displacement (C-CPR30, n = 12), followed by resuscitation protocol with ventilation, defibrillation and intravenous epinephrine (adrenaline). Measurements and main results: Aortic and right atrium blood pressure was measured with micromanometers. Regional blood flows were measured with microspheres. Coronary perfusion pressure during A-CPR was significantly higher as compared to C-CPR without epinephrine (A-CPR versus C-CPR20 versus C-CPR30; 16 +/- 1 mmHg versus 7 +/- 2 mmHg versus 11 +/- 2 mmHg, p < 0.05). p < CPR improved both myocardial flow without epinephrine (A-CPR versus C-CPR20 versus C-CPR30; 23% versus 0% versus 4%; percent of baseline, p < 0.05) and cerebral blood flow (40% versus 4% versus 19%, percent of baseline, p < 0.05). Sixteen of 22 animals receiving A-CPR regained spontaneous circulation and survived; 14/22 had normal cerebral. performance (CPC1). Four of 12 animals receiving C-CPR30 regained spontaneous circulation and survived, but only one animal had normal neurological function (14/22 versus 1/12, p < 0.0001). No animal receiving C-CPR20 achieved spontaneous circulation. At necropsy, 67% of C-CPR30 had rib fracture and 33% showed lung injury, while A-CPR and C-CPR20 resulted in no detectable injuries. Conclusions: Improved hemodynamics with AutoPulse performed CPR results in improved neurologically intact survival without subsequent thoracic or pulmonary injuries in this porcine model of prolonged cardiac arrest. (c) 2005 Elsevier Ireland Ltd. All. rights reserved.