目的　探讨机血回输指征及其对凝血功能的影响。方法　全组先天性心脏病 5 0例行机血回输 ,其中非紫绀型 48例 ,轻度紫绀型 2例。在围手术期不同的时间 :术前、预充后、转流 3min、30min、60min、90min机血、和术后 3h、2 4h取血液标本 ,测定血浆游离血红蛋白、白细胞、红细胞、血红蛋白、血小板及血球压积。结果　 5 0例全机血回输量 40 0～ 10 0 0ml,平均 70 0ml(P <0 .0 1)。手术用血量 (4 0 0± 2 0 )ml,术后胸引流量平均 110ml,与同期随机抽样 5 0例非紫绀型心脏病患儿相比 ,其用血量 (80 0± 5 0 )ml,胸引流量 130ml,有显著性差异 (P <0 .0 1)。患儿血浆游离血红蛋白随体外循环时间延长而增高 ,90min时达峰值 (2 36 .9± 131.2 )mg/L ,术后 2 4h恢复至正常。结论　①小儿体外循环手术中 ,对血浆游离血红蛋白的监测 ,可以较好地反映出红细胞的破坏情况。转流时间在90min以内者 ,机血回输不影响术后凝血功能及肾功能 ,并可以减少库血用量。②紫绀患儿 ,自身红细胞在氧合情况下较易受到破坏 ,术后机血直接回输应慎重。 Objective To investigate the indications of blood transfusion and its influence on the coagulation function. Methods A total of 50 consecutive patients with congenital heart disease underwent transfusion, of which 48 were non-cyanotic and 2 were mild cyanotic. Blood samples were collected at 3, 30, 60 and 90 minutes after operation and pre-filled at 3 and 30 min, and blood samples were collected at 3 and 24 hours after operation. Plasma free hemoglobin, white blood cells, erythrocytes, hemoglobin, platelets And hematocrit. Results 50 cases of whole blood blood transfusion 40 0 ​​~ 100ml, with an average of 70ml (P <0.01). The amount of blood used for surgery (400 ± 20) ml and postoperative chest drainage was 110 ml on average. Compared with children with non-cyanotic heart disease in a random sample of 50 at the same period, the blood volume (80 0 ± 50) ml, chest drainage 130ml, there was a significant difference (P <0.01). Plasma free hemoglobin in children with extracorporeal circulation increased and reached the peak at 90min (2 36.9 ± 131.2) mg / L, returned to normal 24 hours after operation. Conclusion ① In pediatric cardiopulmonary bypass surgery, the monitoring of plasma free hemoglobin can better reflect the destruction of red blood cells. Transfusion time in less than 90min, transfusion of blood does not affect postoperative coagulation and renal function, and can reduce the amount of blood. ② children with cyanosis, red blood cells themselves in the case of oxygen more vulnerable to damage, postoperative blood transfusion should be cautious.