兔心肺复苏后经腹腔诱导亚低温的研究

目的 探讨兔心肺复苏后经腹腔灌注低温液体能否诱导亚低温并评价其安全性.方法 实验一:15只成年新西兰兔依据灌注首剂4℃低温液体剂量的不同分为30,40,60,80和100 mL/ks5组,选择鼓膜温度卜降迅速、稳定的一组连接腹腔灌流装置(专利号Z1200820201265)维持亚低温12h,随后进行复温,并以该组的首剂剂量作为实验二的首剂量.观察血浆生化指标的变化和肝、小肠、肾组织的损伤情况.实验二:12只成年新西兰兔,用电致颤的方式建立心肺复苏(CPR)模型,自主循环恢复(ROSC)后向腹腔内灌入首剂4℃低温液体,达到目标温度后连接腹腔灌流装置维持业低温12h,观察生化指标的变化.腹腔灌液前后生化指标的比较用配对t检验,P<0.05为差异具有统计学意义.结果 实验一:兔腹腔内灌注80 mL/kg低温液体后鼓膜温度(30±2.00)min达到目标温度,通过腹腔灌流装置能稳定维持亚低温和缓慢复温,腹腔灌液后没有出现生化指标的紊乱和造成肝、肾、肠的组织学损伤.实验二:ROSC后兔腹腔内灌注80mL/kg 4℃低温液体后鼓膜温度(26.00±6.99)min达到目标温度,腹腔温度不足10min达到甘标温度,ROSC后腹腔内灌注4℃低温液体没有出现生化指标的紊乱.结论 兔心肺复苏后经腹腔灌注低温液体能安全、快速诱导亚低温.

Preliminary study of hypothermia induced by intraperitoneal cooling in rabbits after cardiopulmonary resuscitation

Objective To explore the safety and rate of intraperitoneal cooling in rabbits after cardiopulmonary resuscitation(CPR). Method There were two experiments. In the experiment one: 15 healthy adult NewZealand rabbits were divided into five groups as per the various amounts, 30, 40, 60, 80, and 100 mL/kg, of priming volume of 4 ℃ cold balanced salts solution injected into peritoneal cavity of rabbits. After injection of priming cold solution, the tympanic temperature between 33 ℃～ 35 ℃. For the maintenance of this mild hypothermia, a intraperitoneal infusion device(patent number ZL200820201265) was connected to the rabbits. The rabbits were rewarmed by using the same device after 12-hour hypothermia. The biochemical parameters were assayed during the experiment. After the rabbits were sacrificed, the liver, ileocecal junction of intestine and kidneys were removed to fix them in 3 % formalin, and examined by using H.E. staining. In the experiment two, another 12 healthy adult New Zealand rabbits were induced into ventricular fibrillation by alternating electric current and then gave CPR for 2 minutes. After return of spontaneous circulation(ROSC), the priming volume of 4 ℃ cold liquid was infused into peritoneal cavity of rabbits, and then the rabbits were connected to the intraperitoneal cooling device to maintain hypothermia for 12 hours. Matched-pairs t test was used for the comparison of biomarkers before and after intraperitoneal cooling. A two-tailed value of P < 0.05 was considered statistically significant. Results In the experiment one, the tympanic temperature of rabbits with priming volume of 80 mL/kg cold solution was decreased quickly reaching the target temperature in(30±2.00) minutes. During the induction of hypothermia, the intraperitoneal temperature reached the target temperature in less than 10 minutes, and was 1 -2℃ lower than the tympanic temperature during the maintenance of hypothermia. The intraperitoneal cooling did not cause damage in the liver, ileocecal junction of intestine and kidney, and did not alter the biomarkers. In the experiment two, the tympanic temperature of rabbits after ROSC was decreased quickly after intraperitoneal infusion of 80 mL/kg 4 ℃ cold solution, and reached the target temperature in(26.00±6.99) minutes, and the intraperitoneal temperature was lowered to reach the target temperature in less than 10 minutes. This cooling method after CPR didn' t disturbance water-electrolyte and acid-base balance. Conclusions The intraperitoneal cooling can safely and quickly induce hypothermia after CPR in rabbits.