犬低温体外循环手术及其灌注管理的试验研究

STUDIES ON OPERATION AND PERFUSION MANAGEMENTFOR HYPOTHERMIC CARDIOPULMONARY BYPASS(CPB) IN THE CANINE

试验应用现代体外循环技术，实施完全心肺转流的低温体外循环，首次在我国兽医临床建立了２８只犬低温体外循环实验模型。探索适用于小动物心脏直视手术的体外循环手术操作、心脏停搏与复苏、体外循环灌注管理的技术方法。研究表明，选择右侧第４肋间进胸，从右心房施行前后腔静脉插管及升主动脉根部置供血管是简便易行的手术通路。采用部分晶体液与全血作预冲液，体外转流维持中度血液稀释（平均２３６８±３２７％），最低温度控制２６℃左右（平均２６１４±０７７℃），血流复温至３６℃左右（平均３５９７±０６８）开放升主动脉，转流中灌注压维持５０～９０ｍｍＨｇ（平均７２±１３ｍｍＨｇ），灌注流量８０～１００ｍＬ·ｋｇ－１·ｍｉｎ范围，是低温体外循环下开展犬心内直视手术成功的基本保障。采用冷晶与冷温血停搏液不同灌注。结果显示，冷温血停搏液联合灌注组心脏自动复跳率最高，并且复跳迅速，心搏有力，正性肌力药应用剂量小，复跳后辅助循环时间明显低于冷晶停搏液灌注组（Ｐ＜００５）。

おn order to explore the adquate techniques of operation, arrest and recovery of heart, and the management of perfusion for CPB in the dog, hypothermic CPB models of twenty-eight mongrel dogs were established for the first time in the field of veterinany in China The operation confirmed that thoracotomy through the right chest wall at 4th rib is a good access for canulation of the ascending aorta and right auricle in the dogs The management of perfusion indicated that: whole blood and crystalloid solution should be adopted for the priming, the moderate dilution be maintained; the lowest temperature be controlled to 26℃ or so; rewarming temperature be increased to 36℃ or so to be opened aortic cross-clamp; perfusion pressure be maintaied 50～90 mmHg during the CPB; the pump flow rate 80～100 mL(kg·min)-1 They are basical condition for performing successful cardiac surgery of the dogs Clinical results also showed that∶With united infusion of cold and warm blood cardioplegia, the rate of automatical recovery beat was the highest among the four groups, the use of vaso pressor and antiarrhytic drugs was the lower of doses, the continuous CPB time obviously decreased