经食道-胸壁电刺激建立兔心脏骤停模型

Ventricular Fibrillation Induced by Transoesophageal-chest Wall Electrode: A Simpler Cardiac Arrest Model in Rabbits

【目的】建立一种更为简单、便捷、成功率高的兔心脏骤停模型。【方法】经食道插入食道调搏电极至心脏水平,在心前区心搏最明显处皮下插入针灸针形成电流回路,用恒定35mA交流电诱发心脏骤停,无干预观察5 min后进行心肺复苏。分别记录15只新西兰大白兔达到心脏骤停标准的时间、停止刺激时的心律、复苏开始前的心律、心肺复苏时间、除颤次数、给药次数、自主循环恢复率、自主循环恢复后机械通气时间、自主循环恢复后生存时间及72 h生存率。【结果】本实验中的15只兔全部诱发心脏骤停成功。从有效电刺激开始到成功诱发心脏骤停的时间为(26±10)s。电刺激结束时室颤发生率为100%(15/15),无心脏停搏及无脉性电活动发生,在无干预观察期内无自动复律现象。在心肺复苏开始时心电图表现为室颤的比例为73.3%(11/15),无脉性电活动的比例为26.7%(4/15)。心肺复苏用时(200±136)s,除颤次数(1.00±0.76)次,静脉注射肾上腺素次数(2.40±1.12)次,自主循环恢复率93.3%(14/15),自主循环恢复后机械通气时间(40±17)min。自主循环恢复后0～6 h死亡率为6.7%(1/15),6～24 h内死亡率60(9/15),24～72 h时存活率为26.6%(4/15)。【结论】经食道-胸壁定流电刺激方式诱发兔心脏骤停模型操作简单、重复性好、复苏成功率高,并发症少,是一个较为理想的研究心肺脑复苏的模型。

【Objective】 To establish a simple,stable and high success rate cardiac arrest（CA） model in rabbits.【Methods】Cardiac ventricular fibrillation（VF） was induced in 15 New Zealand rabbits by transoesophageal-chest wall electrode with 35mA alternating current.Five minutes after onset of CA,conventional cardiopulmonary resuscitation（CPR） was initiated.The time spent on inducing cardiac arrest,the cardiac rhythm when the electric stimulation was stopped,the cardiac rhythm when the CPR was started,the time spent on CPR,the defibrillation frequency,the administration frequency,the rate of restoration of spontaneous circulation（ROSC）,the mechanical ventilation time after ROSC,the life time after ROSC and the 72 h survival rate of 15 rabbits were recorded respectively.【Results】 All of 15 rabbits were successfully induced cardiac arrest.The inducing time was 26.47 ± 10.36 s.When the electric stimulation was stopped,all cardiac rhythm was ventricular fibrillation（15/15）,no pulseless electrical activity and asystole occurred.During the observation of nonintervention,no automatic cardioversion phenomenon occurred.When the CPR was started,electrocardiogram indicated VF occurred in 73.3% of the rabbits（11/15）and pulseless electrical activity occurred in 26.7% of the rabbits（4/15）.The time spent on CPR was 200.07 ± 136.00 s.The defibrillation frequency was 1.00 ± 0.76.The frequency of intravenous injection of adrenaline was 2.40 ± 1.12.The rate of ROSC was 93.3%（14/15）.The mechanical ventilation time after ROSC was 40.46 ± 17.05min.The death rate within 6h after ROSC was 6.7%（1/15） and the 72h survival rate was 26.6%（4/15）.【Conclusion】 The model of cardiac arrest in rabbits induced by transoesophageal-chest wall electric stimulation is very simple operation,and has a stable result and high success rate.It is a ideal animal model for cardiopulmonary resuscitation study.