大鼠机械式胸外按压心肺复苏模型的建立

目的 探索用机械式胸外按压复制大鼠心肺复苏（cardiopulmonary resuscitation,CPR）模型的可行方法。方法 成年雄性SD大鼠,随机分为对照组（n=6）与模型组（n=10）。10%水合氯醛腹腔注射麻醉后行气管插管和左侧股动脉插管。在监测心电图与动脉血压条件下,模型组行气管阻塞（tracheal obstruction,TO）,心脏骤停（cardiac arrest,CA）出现2 min用呼吸机辅助和自制动物胸外按压仪行CPR。结果 模型组TO后迅速出现自主呼吸停止,紫绀,心律失常,4～5 min出现心脏停搏,动脉收缩压降至40 mmHg以下,脉压消失,CA出现。2 min后给予CPR,8只大鼠自主循环恢复（return of spontaneous circulation,ROSC）,并出现一过性再灌注心律失常,6只大鼠恢复意识并存活24 h。血液生化分析提示模型组大鼠存在电解质紊乱、酸中毒、肾功能损害、心肌酶谱升高。病理学切片观察发现模型组大鼠心肌横纹溶解,肾小球无复流,神经元减少,肺淤血等器官损害。结论 机械式胸外按压可以提供CA大鼠CPR所需的基本心输出量,可以成功建立大鼠CPR模型。

Establishment of a rat model of cardiopulmonary resuscitation with mechanical chest compression

Objective To explore the feasibility of mechanical chest compression to establish a rat model of cardiopulmonary resuscitation (CPR).Methods 4-month old healthy male Sprague Dawley rats were randomly divided into control group (n=6) and model group (n=10). After induction of anaesthesia with 10% chloraldurate (3 ml/kg, i.p.), tracheal intubation and left femoral artery cannulation were performed. Under electrocardiographic and artery blood pressure monitoring, tracheal obstruction (TO) was performed to rats in model group. At 2 min after the cardiac arrest (CA) occurred, CPRs were administered to the rats using a self-made animal chest compressor, which provided chest-compression at a rate of 200 bpm. Results Shortly after TO, rats in the model group had respiratory arrest, cyanosis and arrhythmia. Electrocardiography indicated that CA occurred within 4-5 min, with a decreased artery systolic blood pressure (<40 mmHg) and a zero pulse pressure. Return of spontaneous circulation (ROSC) after the CPR was successfully achieved in 8 rats (80%), with a transient reperfusion arrhythmia. Finally, 60% of the rats (n=6) recovered to consciousness and survived for 24 hrs. The serum biochemical analysis indicated that there were electrolyte disturbances, acidosis, impaired renal functions and increased myocardial enzyme spectrum. Pathological examination revealed cardiac rhabdomyolysis, no-reflow phenomenon in renal glomeruli, decrease of neurons and pulmonary congestion in the model group rats. Conclusions Mechanical chest compression can provide minimal cardiac output for the requirement of CPR incardiac arrestin rats. It is feasible to establish rat CPR model with the mechanical chest compression.