真空辅助静脉引流技术的实验研究

Animal experimental study of vacuum assisted venous drainage technique during cardiopulmonary bypass

目的观察体外循环中真空辅助静脉引流技术(VAVD)对红细胞的损伤作用,测量预充液量及输血量。方法幼猪10头随机分成两组,接受体外循环转流术。一组为重力静脉引流组(GVD),另一组是真空辅助静脉引流组(VAVD)。两组均采用常规体外循环回路、膜肺式氧合器及与之配套的硬塑静脉贮血室。VAVD组施加-25^-35mmHg的真空微负压到膜肺静脉贮血室。体外循环转流前、转流30min、60min两组分别采血标本测血清中乳酸脱氢酶、总胆红素。测量体外循环管道长度、预充液量、血液稀释程度及红细胞压积达25%时需要输血量。结果两组间总胆红素和乳酸脱氢酶数据无显著差异(P>0.05)。与GVD组相比较,VAVD组能缩短体外循环回路长度2.7m,减少预充液450ml。转流中红细胞压积为VAVD组(26.80±1.94)%,GVD组(21.60±3.50)%。维持红细胞压积25%时,GVD组需预充用血230ml。结论VAVD技术能促进体外循环中静脉血液引出到膜肺氧合器,降低预充量、节约用血、不会增加红细胞损伤。

Objective To observed the impact of vacuum assisted venous drainage （VAVD） technique on erythrocytic damage and measured the volume of prime solution and blood transfusion during the extracorporeal bypass.Methods Ten juvenile pigs were divided into two groups randomly. All of them received the cardiopulmonary bypass. One group was gravitational venous drainage （GVD）. The other one was vacuum assisted venous drainage （VAVD）. The conventional extracorporeal circuit, membrane oxygenator and fitting hard plastic shell venous reservoir was used in both groups. In VAVD, the vacuum micro negative pressure of -25 - -35 mmHg was administered to the venous reservoir. The blood samples were taken before CPB and 30min, 60min during the bypass for testing LDH and total bilirubin in serum. To detemine the length of extracorpoml circuit, the prime volume, the level of hemodilution and the volume of blood transfusion requirment when the hematocrit reach up to 25%. Results The amount of LDH and total bilirubin was not obvious difference between the two groups （ P 〉 0.05）. Being Compare with GVD group, the length of extracorporal circuit was shortened 2.7m and the prime solution was decreased 450ml in VAVD group. The hematocrit was （26.80± 1.94）% in VAVD and （21.60± 3.50）% in GVD during bypass. For keeping 25% hematocrit,the prime required 230ml blood in GVD. Condusion The VAVD technique can promote venous blood drainage into oxygenator, decrease prime solution, save blood volume, and can not increase the erythrocyte damage during cardiopulmonary bypass.