Miniaturized mechanical chest compressor improves calculated cerebral perfusion pressure without compromising intracranial pressure during cardiopulmonary resuscitation in a porcine model of cardiac arrest.
OBJECTIVE
One of the major goals of cardiopulmonary resuscitation (CPR) is to provide adequate oxygen delivery to the brain for minimizing cerebral injury resulted from cardiac arrest. The optimal chest compression during CPR should effectively improve brain perfusion without compromising intracranial pressure (ICP). Our previous study has demonstrated that the miniaturized mechanical chest compressor improved hemodynamic efficacy and the success of CPR. In the present study, we investigated the effects of the miniaturized chest compressor (MCC) on calculated cerebral perfusion pressure (CerPP) and ICP.


METHODS
Ventricular fibrillation was electrically induced and untreated for 7min in 13 male domestic pigs weighing 39±3kg. The animals were randomized to receive mechanical chest compression with the MCC (n=7), or the Thumper device (n=6). CPR was performed for 5min before defibrillation attempt by a single 150J shock. At 2.5min of CPR, the epinephrine at a dose of 20μg/kg was administered. Additional epinephrine was administered at an interval of 3min thereafter. If resuscitation was not successful, CPR was resumed for an additional 2min prior to the next defibrillation until successful resuscitation or for a total of 15min. Post-resuscitated animals were observed for 2h.


RESULTS
Significantly greater intrathoracic positive and negative pressures during compression and decompression phases of CPR were observed with the MCC when compared with the Thumper device. The MCC produced significantly greater coronary perfusion pressure and end-tidal carbon dioxide. There were no statistically significant differences in systolic and mean ICP between the two groups; however, both of the measurements were slightly greater in the MCC treated animals. Interestingly, the diastolic ICP was significantly lower in the MCC group, which was closely related to the significantly lower negative intrathoracic pressure in the animals that received the MCC. Most important, systolic, diastolic and mean calculated CerPP were all significantly greater in the animals receiving the MCC.


CONCLUSIONS
In the present study, mechanical chest compression with the MCC significantly improved calculated CerPP but did not compromise ICP during CPR. It may provide a safe and effective chest compression during CPR. Protocol number: P1205.
Weil Institute of Critical Care Medicine, Rancho Mirage, CA, United States; Department of Emergency Medicine, Yuyao People's Hospital, Medical School of Ningbo University, Ningbo, China. Electronic address: Jeff.xu11@gmail.com.
Jiefeng
J
Xu
Weil Institute of Critical Care Medicine, Rancho Mirage, CA, United States. Electronic address: xianwenhu@yahoo.com.cn.
Xianwen
X
Hu
Weil Institute of Critical Care Medicine, Rancho Mirage, CA, United States. Electronic address: Yangzhengfei@vip.163.com.
Zhengfei
Z
Yang
Weil Institute of Critical Care Medicine, Rancho Mirage, CA, United States. Electronic address: Mike_wu@weiliccm.org.
Xiaobo
X
Wu
Weil Institute of Critical Care Medicine, Rancho Mirage, CA, United States; Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States. Electronic address: Jbisera@weiliccm.org.
Joe
J
Bisera
Weil Institute of Critical Care Medicine, Rancho Mirage, CA, United States; Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States. Electronic address: Shijie.sun@aol.com.
Shijie
S
Sun
Weil Institute of Critical Care Medicine, Rancho Mirage, CA, United States; Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States; Department of Emergency Medicine, School of Medicine of the University of California, San Diego, CA, United States. Electronic address: Wanchun.tang@me.com.
Wanchun
W
Tang
D000818:Animals; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D002560:Cerebrovascular Circulation; D004195:Disease Models, Animal; D006323:Heart Arrest / Q000628:therapy*; D006336:Heart Massage / Q000295:instrumentation*; D007427:Intracranial Pressure; D008297:Male; D008904:Miniaturization; D011897:Random Allocation; D013552:Swine
Cardiac arrest; Cardiopulmonary resuscitation; Cerebral perfusion pressure; Hemodynamics; Intracranial pressure; Miniaturized chest compressor