高龄高危心脏瓣膜置换术患者的体外循环管理

Management of cardiopulmonary bypass during heart valve replacement surgery in high age and high risk patients

目的总结高龄高危心脏瓣膜置换术患者的体外循环(Cardiopulmonary bypass,CPB)管理经验。方法2008年8月至2017年8月广州军区广州总医院对54例高龄(年龄>70岁)高危心脏瓣膜患者行瓣膜置换术。CPB中:心肌保护采用1:4(晶:血)冷灌注液,每隔30 min以冷血半钾停搏液重复灌注,常规监测患者的心电图、动脉压、中心静脉压和混合静脉血氧饱和度,定时行血气分析、活化全血凝固时间(activated clottingtime of whole blood,ACT)、电解质以及尿量监测,保持动脉血pH值7.35～7.45,静脉血氧饱和度65%以上,ACT维持在480 s以上,术中灌注流量2.0～2.6 L/(min·m^2),灌注压维持在60～80 mmHg(1mmHg=0.133kPa)。结果全组CPB时间112(87～258)min,主动脉阻断时间74(54～174)min,术毕心脏自动复搏率78%,围术期死亡3例,余均痊愈出院。结论高龄高危心脏瓣膜置换术风险大,对术中管理要求高,在CPB中选用性能良好的材料如膜肺,合理的预充,充分的组织灌注,有效的心肌保护,适度的辅助循环,以及改良超滤,可降低并发症发生率和病死率,是手术成功的保证。

Objectives To sununarize the experience of cardiopulmonary bypass （CPB） during heart valve replacement surgery in high age and high risk patients. Methods Between August 2008 and August 2017, a total of 54 patients with high age （〉70 years old） and high risk were performed heart valve replacement in General Hospital of Guangzhou Military Command. Cold oxygenated hyperkalemia blood cardioplegia at the ratio of 1 to 4 was employed. Cold blood half potassium cardioplegia was repeated perfusion every 30 min. Electrocardiography, artery pressure, central venous pressure and mixed venous oxygen saturation, blood gas analysis, activated clotting time of whole blood （ACT） , electrolytes and urine volume of the patients were monitored. Artery blood pH maintained at 7.35-7.45, venous oxygen saturation maintained 〉65%, ACT maintained 〉480 s. Perfusion was obtained at 2.0-2.6 L/（min-m2） to maintain the perfusion pressure at 60-80 mmHg （1 mmHg=0.133 kPa）. Results CPB duration was 112（87-258） min, and aortic occlusion duration was 74 （54-174） min. The ratio of spontaneous rhythm recovery was 78%. There were 3 perioperative deaths, and the other patients were all cured and discharged. Conclusions During valve replacement surgery, good CPB materials, right priming, sufficient tissue perfusion, effective cardioprotection proper circulation assist and modified ultrafiltration are associated with less complications and a low mortality.