EXTRACORPOREAL LING AND HEART ASSIST COMBINED WITH HYPOTHERMIA FOR BRAIN RESUSCITATION

我们开发了一种新的计算机辅助体温调节系统，可以自动将狗的体温从正常体温控制到32摄氏度。该系统可连续调节体温3天，最小偏差为0.4 ℃，每分钟存储一次体温、血流动力学和脑电功率谱等数据，同时测量全身各部位的温度，发现颈静脉血、枕大池和肺动脉血的温度与脑温接近。直肠温度与脑温相关，但低温时腹泻和粘液便有时会导致温度不准确，从而导致脑温的不正确反映。结果表明，肺动脉血温度是观察犬长时间体外心肺辅助（ECLHA）联合亚低温时脑温变化的最佳方法。ECLHA经常并发出血。体温过低也会诱发出血倾向。因此，我们检查了血小板聚集试验和血栓弹力图。试验证实，24小时内32 ℃的低温不太可能加重凝血。因此，我们最终确定了ECLHA联合32 ℃低温复苏方案，仅24 h ECLHA联合32 ℃低温复苏成功，心脏骤停15 min，无神经系统并发症。将需要进一步的研究来建立ECLHA结合低温作为复苏的手段。

We have developed a new computer-assisted thermoregulator system to control the body temperature automatically from normothermia to 32ﾟC in dogs. The system could regulate hypothermia of 3 days with a slight aberrations of 0.4ﾟC and storage the data every one minute, including the temperatures, hemodynamics and the power spectrogram of EEG.The simultaneous measurement of temperatures in various portions of the body revealed that temperatures in the jugular venous blood, the cisterna magna and the pulmonary artery blood approximated the brain temperature. The rectal temperature correlated the brain temperature, but diarrhea and mucous stool during hypothermia sometimes caused the inaccurate temperature, leading to incorrect reflection of the brain temperature. These results certified that the temperature of the pulmonary artery blood was a most suitable means to observe the brain temperature closely during prolonged extracorporeal lung and heart assist (ECLHA) combined with mild hypothermia in dogs. ECLHA is frequently complicated with hemorrhage. Hypothermia also induces bleeding tendency. Thus we have examined the test of platelet aggregation and thromboelastogram. The test confirmed that the hypothermia of 32ﾟC within 24 h was unlikely to aggravate blood coagulation. Therefore we decided finally the resuscitation protocol of ECLHA combined with hypothermia of 32ﾟC limited within 24 h.The only ECLHA of 24 h combined with hypothermia of 32ﾟC resuscitated successfully dogs with cardiac arrest of 15 min without neurologic sequlae. The further studies will be required to establish ECLHA combined with hypothermia as a means for resuscitation.