Abstract 59: Miniaturized Mechanical Chest Compressor for Cardiopulmonary Resuscitation
After cardiac arrest, effective and uninterrupted chest compression provides blood flow to the vital organs and improves the success of CPR. In this study, we investigated the hemodynamic efficacy of a newly developed pneumatically driven miniaturized mechanical chest compressor (MCC) in a porcine model of cardiopulmonary resuscitation (CPR). Our hypothesis was that because of the design of the MCC, it should produce better hemodynamic efficacy with lesser compression depth. Ventricular fibrillation (VF) was induced in domestic pigs weighing between 35 and 36 kg. CPR was initiated after 7 minutes of untreated VF. Animals were randomized to receive mechanical chest compression with either the MCC or the conventional device (Thumper). Both devices provided the same compression rate of 100/min. The initial compression depth was adjusted to achieve a coronary perfusion pressure (CPP) above 12 mm Hg. After 5 minutes of CPR, a single 150J defibrillation (DF) was delivered. If resuscitation was not successful, CPR was continued for 2 minutes before the next DF. The protocol was continued until successful resuscitation or for a total of 15 minutes. All animals were resuscitated except 1 from the Thumper group. During CPR, significantly greater CPP with lesser compression depth was observed in the MCC group (Table). Significantly greater intrathoracic positive (31±6 vs 10±7 mm Hg, p<0.01) and negative pressures (-10±3 vs -3±2 mm Hg, p<0.01) were observed in MCC treated animals. Significantly shorter durations of CPR (5±0 vs 11±4 min, p<0.05) and lesser numbers of DF (1±0 vs 9.8±11, p<0.05) that were required for achieving successful resuscitation were observed in animals treated with MCC. None of the MCC treated animals had rib fracture compared with the Thumper group with an average of 2.75±1.9 rib fractures (p<0.05). MCC substantially improved hemodynamic efficacy and successful of CPR with significantly less injury.
- © 2011 by American Heart Association, Inc.