不同程度血液稀释在小儿体外循环中的应用效果观察

目的探讨小儿体外循环心脏手术血液稀释的方法及血液稀释的安全性.方法总结分析350例小儿体外循环心脏手术过程中血液稀释度及对体外循环转流中组织的灌注效果.结果350例患儿中血液稀释后最低红细胞压积(HCT)8%～101例(A组),HCT11%～15"7例(B组),HCT 16%～20p例(C组),HCT 21%～30'例(D组),HCT 31%~35%4例(E组),5组患儿开放升主动脉时心肌自动复跳,但无明显差异(P＞0.05),但A组患儿应用正性肌力药物的例数和体外循环辅助时间明显高于其他四组患儿(P＜0.05),其它四组患儿间无明显差别(P＞0.05).结论休外循纠的血液稀释程度对体外循环心脏手术的心脏自动复跳率无明显的影响,但影响体外循环的辅助时间和正性肌力药物的用量;对于早期可以维持较低的红细胞压积,在开放升主动脉时,应尽量使红细胞压积达到20%以上,以减少体外循环辅助时间和减少术中应用正性肌力药物.

Clinical effect of different degree hemodilution on children cardiosurgery in exreacorporeal circulation

Objective:To investigate the methods of hemodilution and hemodilution reliability for children cardiosurgery in exreacorporeal circulation.Methods:The hemodilution degree and perfusion result of cardiopulmonary bypass(CPB)in 350 children cases were analysed.Results:In 350 cases,haematocrit which was the lowest was 8%～10% in 31 cases(group A),HCT was 11%～15% in 227 cases(group B),16%～20% in 70 cases(group C); 21%～30% in 27 cases(group D); and 31%～35% in 4 cases(group E).There were no obvious difference in the rates of heart auto-beat when opened the ascending aorta(P＞0.05).but in group A the numbers of cases using reinforcement muscle power drugs and exreacorporeal circulation assistant time were obviously larger then those of the other four groups(P＜0.05).No obvious difference was found among the other four groups(P＞0.05).Conclusions:The hemodilution degree didn't affect the rate of heart auto-beat in children with cardiosurgery,but it affected the cardiopulmonary bypass assistant time and the dose of reinforcement muscle power drugs.In earlier period of cardiopulmonary hypass,the haematocrit could be low;when the ascending aorta was opened,if possible,the heamaltocrit should be kept at＞20% to reduce the cardiopulmonary bypass assistant time and dose of the reinforcement muscle power drug during operation on heart.