小型猪心内直视手术的体外循环管理

目的研究医学手术实验用小型猪心脏手术的体外循环（CPB）管理及效果。方法实验用小型猪30头，分为两组，分别于CPB下行心脏停跳手术（停跳组）15例及不停跳并行心脏手术（非停跳组）15例。基础麻醉起效后仰卧位固定于手术台上，开放耳缘静脉，行气管插管盾连接呼吸机，经隐动脉及右颈内静脉置管监测动静脉压，静吸复合麻醉。采用鼓泡式氧合器及儿童管道，溺低温下流量60-80ml／（kg·min），平均动脉压（MAP）50-60mmHg，α稳态血气管理方式，停跳组用冷晶体高钾停搏液诱导停搏，心脏复跳后调整流量脱离CPB。根据情况使用相应的血管活性药物支持循环，止血关胸。呼吸恢复后拔除气管导管及动脉监测管，可进食后拔除静脉输液管。实验中记录麻醉药用量，麻醉及CPB时间，术中生命体征，各项血流动力学参数，动脉血气，呼吸机辅助时间，CPB后血管活性药物用量，术后一周存活状况，并评价CPB效果。结果30例均顺利完成手术脱离CPB。各期血流动力学维持较平稳，停跳组3例术后7天内死亡，非停跳组无死亡。停跳组CPB后循环功能较非停跳组差，并发症多，需要更长的CPB后并行辅助、呼吸机支持及药物辅助治疗。结论小型猪的CPB过程中需要合理血液稀释、避免心脏停跳和积极的药物支持，减轻缺血再灌注损伤和术后积极有效的维护循环功能对于手术成功有着重要意义。

The management of cardiopulmonary bypass in open-heart surgery on Swines

Objective To investigate the experiences and results of cardiopulmonary bypass management in Swines.Methods Thirty Swines were divided into two groups: the cardiac arrest group(n=15) underwent tricuspid valve replacement with autologous pericardium with aortic occlusion,and the parallel group(n=15) receiving the operation without aotic occlusion.The Swines were fixed on the operation table in supine position after basic anesthesia.Then their ear veins were opened.Tracheal intubation was performed and the ventilator was connected.Tubes were palced in the saphenous artery and the right internal jugular vein to monitor the artery and venous pressure.Then the intravenous inhalational anesthesia was completed.The bubble oxygenators and children’s circuits were chosen.During cardiopulmonary bypass,the flow rate was maintained between 60-80 ml/(kg·min),mean arterial blood pressure was maintained between 50-60 mm Hg with mild hypothermia,and theα-state blood gas management was applied.High potassium cardioplegia was given to induce cardiac arrest.After cardiac resuscitation,the flow rate was gradually decreased until cardiopulmonary bypass was totally weaning off.Corresponding vasoactive drugs were used to support the circulation according the pigs’ condition.After stopped bleeding,pigs’ chest was closed.The tracheal catheter and arterial duct were removed after the recovery of respiratory,and the venous duct was removed after swines could take food.The dosages of anesthetics,maintenance times of general anesthesia CPB time,intraoperative vital signs,hemodynamic parameters,arterial blood gas,ventilator time,dosages of vasoactive drugs and survival rate at 1 week were recorded.Then the effects of CPB were evaluated.Results All Swines underwent successful operation and weaning from cardiopulmonary bypass with stable hemodynamics in each period.The cardiac arrest group had 3 pigs died in 1 week after the operation and the parallel group had none.The pigs of the cardiac arrest group also had worse circulation function,more complications,more vasoactive drugs,longer time of ventilator and assisted circulation.Conclusion The CPB of the Swines requires appropriate hemodilution,avoiding cardiac arrest and active drug support.Alleviating ischemia-reperfusion injury,actively and effectively maintening the circulation function have important significance for the operation success.