Rabbit models of post-cardiac arrest syndrome induced by transcutaneous electrical stimulation on the myocardium

Abstract

Objective To establish a simple and convenient model of post-cardiac arrest syndrome (PCAS) in rabbits.Methods The experiment site in Xiamen university animal experiment center.Twenty five New Zealand rabbits were selected,male and female unlimited.Two acupuncture needles connected to the anode and cathode of a stimulator were transcutaneously inserted into the myocardium as electrode.The stimulating current was steered to the myocardium and maintained for 3 minutes to induce cardiac arrest (CA).Cardiopulmonary resuscitation (CPR) was performed at 6 minutes after a period of nonintervention.The levels of white blood cell (WBC),alanine aminotransferase (ALT),creatinine (Cr),troponin Ⅰ (Tn Ⅰ),brain natriuretic peptide (BNP),partial pressure of oxygen (PaO2),partial pressure of carbon dioxide (PaCO2) in arterial blood and the heart rate,body temperature,blood pressure were measured before CA and 0,24,48,72 hours after ROSC.Rabbits were sacrificed and microstructure injury was observed using electric microscope after ROSC 72 h.Comparisons among two groups were studied by using IndependentSamples t Test.Statistical comparisons within groups were analyzed by using paired t-test.Results The rate of ROSC in rabbits was 22/25.Twenty rabbits were survived in systemic inflammatory response syndrome (SIRS) and myocardial injury and dysfunction at 24 h after ROSC.Eleven rabbits were survived in post-resuscitation multiple organ dysfunction syndrome (PR-MODS) at 72 h after ROSC.TNF-α level peaked at 24 h after ROSC,and then decreased gradually.The procalcitonin (PCT) concentration significantly increased after ROSC 24 h.Conclusions The model of CA in rabbits induced by transcutaneous electrical myocardial stimulation required low-intensity current and showed typical pathophysiological process of PCAS,the model had high success rate and long survival time.The model appeared typical brain injury,myocardial dysfunction,ischemia-reperfusion injury.It may be an ideal animal model for investigation on PCAS. Key words: Electrical stimulation; Cardiac muscle; Cardiopulmonary resuscitation; Post-cardiac arrest syndrome; Animal models