A model of cardiac arrest and cardiopulmonary resuscitation in rats

Objective To establish a cardiac arrest and cardiopulmonary resuscitation model. Methods Thirty Sprague-Dawley（SD） rats were randomly divided into control group（n=15） and epinephrine group（n=15）.A rat model of cardiac arrest was established with an alternate current（AC） electrode placed in esophagus.Five minutes after the onset of cardiac arrest,cardio-pulmonary resuscitation（CPR） was initiated.Cardiac compression was performed with a machine made by our group.Distribution of cardiac arrest types,pace-inducing time,recovery of self circulation（ROSC） and success resuscitation were observed.The rats were killed to examine whether there was any burn of the esophagus mucosa and heart,and rupture of the abdominal organs. Results Cardiac arrest was successfully induced in all rats,including ventricular fibrillation（VF） in10 rats（33.3%）,pulseless electric activity（PEA） in 15 rats（50%）,asystole in 5 rats（16.7%）,respectively.The pacing time was 60-150s.The ROSC was achieved in 1 rat of the control group（6.7%） and in 7 rats of the epinephrine group（46.6%）,respectively.The success resuscitation was achieved no rat of the control group（0%） and in 5 rats of the epinephrine group（33.3%）,respectively.Mild burn was observed in esophagus mucosa while no heart burn and rupture of esophagus and abdominal organs were found. Conclusion A rat cardiac arrest model can be established with an AC electrode placed in esophagus.Cardiac compression with a machine can meet the requirements of a standard CPR study in rats.