ABSTRACT
Objective To establish an simple and convenient animal model of cardiac arrest for studying cerebral resuscitation.Method Clean male Sprague Dawley rats were randomly divided into sham group and experimental group.Cardiac arrest was induced by asphyxiation and ice-cold 0.5 mol KCl with blood flow cut off for 5 minutes.Animals were resuscitated with external cardiopulmonary resuscitation (CPR),mechanical ventilation,and epinephrine injection.Blood pressure,heart rate,successful ratio of resuscitation after 72 hours, time of cardiac arrest (T_(CA)) and return of spontaneous circulation (T_(ROSC)) were recorded.Neural deficit scores (NDS) and levels of maleic dialdehyde (MDA) in plasma were evaluated at 3,6,12,24,48,72 hours after ROSC.The damage score of cortex was measured by transmission electron microscope examination at 3 hours and 72 hours after ROSC.Results All the rats in experimental group had cardiac arrest rapidly.T_(CA) and T_(ROSC) were (137.3?10.2) seconds and (64.4?9.3) seconds,respectively,while the successful rate of resuscitation was 82.5%.The lowest NDS was at 3 hours after ROSC,while the NDS increased gradually.After CPR,the level of MDA in plasma increased significantly,slightly declined at 72 hours after ROSC,but still significantly higher than before the model.Electron microscope examination of cortex showed neuron slightly,organelle and astrocyte,but became better after 72 hours post ROSC.Conclusions The model of cardiac arrest was easy to establish,and the data provided was accurate,which is useful to study the mechanism of cerebral resuscitation.