紫绀型先天性心脏病患儿的体外循环再氧合损伤

摘要

目的 通过控制体外循环启动时的吸入氧浓度,研究不同给氧浓度对紫绀型先天性心脏病再氧合损伤的影响及安全性.方法 紫绀型先天性心脏病患儿30例及非紫绀型先天性心脏病患儿10例,根据体外循环初始氧浓度分为4组:紫绀组1(G1),氧分压(PaO2)＜ 120 mm Hg(1 mm Hg =0.133kPa);紫绀组2(G2),PaO2 120 ～＜ 180 mm Hg;紫绀组3(G3),PaO2 180～ ＜250mmHg;非紫绀组(G4),PaO2＞200 mm Hg.体外循环前、体外循环开始后5 min、10 min、开放升主动脉后5 min、术后2h、24h检测血清心肌酶(CK-MB)、肌钙蛋白(cTnI)、白介素6(IL-6)、肿瘤坏死因子α(TNF-α)、超氧化物歧化酶(SOD)、8-异构前列腺素(8-ISO)和S100β蛋白(S100β)浓度,同时记录相应临床指标.结果 CK-MB、cTnI、IL-6、TNF-α、8-ISO、S100β术前4组间差异无统计学意义.体外循环开始后均上升,于体外循环停机前后达峰值,之后逐渐下降,在各时间点指标增高趋势为G3 ＞G2 ＞G1 ＞G4,4组间差异有统计学意义(P＜0.05).SOD在术前G4高于其他3组,差异有统计学意义(P＜0.05)；体外循环开始后各组SOD水平均降低,于升主动脉开放后达最低值,之后逐渐升高,体外循环开始后5 min、10 min、开放升主动脉后5 min、术后2h4个时间点G3 ＜G2 ＜G1 ＜G4,组间差异有统计学意义(P＜0.05),术后24h G1、G2和G3组均低于G4组(P＜0.05),但3组间差异无统计学意义.SvO2、Lac、正性血管活性药物使用情况、机械通气时间和ICU住院时间3个紫绀组间差异无统计学意义,与非紫绀组相比差异有统计学意义(P＜0.05).4组患儿全部生存并顺利出院.结论 低氧启动体外循环可明显降低紫绀型先天性心脏病的再氧合损伤,在常规浅、中低温体外循环结合其他措施可有效降低再氧合损伤；对脑组织氧代谢有可能的潜在影响,在深低温及长时间体外循环供氧方式上还需进一步深入研究.%Objective To investigate the effect and safety of different PaO2 to the reoxygenation injury of cyanotic congenital heart disease through controlling the FiO2 when initiating cardiopulmonary bypass (CPB).Methods Thirty patients with cyanotic congenital heart disease were divided into 3 equal groups according the PaO2 when initiating cardiopulmonary bypass:group 1 (G1,PaO2 ＜ 120 mm Hg) ; group 2 (G2,PaO2 120-180 mm Hg),group 3 (G3,PaO2 180-250 mm Hg),and ten patients with acyanotic congenital heart disease were group 4 (G4,PaO2 ＞ 200 mm Hg).Serum CK-MB,cTnI,IL-6,TNF-α,SOD,8-ISO and S100β were measured before CPB、5 minute after CPB,10 minute after CPB,5 minute after cross clamp releasing,2 hours and 24 hours post operation with intemal jugular vein blood samples.Clinical results were also recorded.Results CK-MB,cTnI,IL-6,TNF-α,8-ISO and S100β3 were all normal without significant differences between them before CPB.After initiation of CPB,their levels in all groups increased,reached the peak before or after the stop of CPB,then gradually declined.At each time point,the levels of these indexes were G3 ＞ G2 ＞ G1 ＞ G4 with significant difference between them (P ＜ 0.05) ; The serum SOD levels of G4 were higher than the other three groups with significant difference(P ＜ 0.05).They all declined after initiation of CPB,reached lowest after cross clamp releasing,then gradually increased.At 5 minute after CPB,10 minute after CPB,5 minute after cross clamp releasing,2 hours post operation,there were significant differences between four groups (P ＜ 0.05),and at 24 hours post operation,the SOD levels of G4 were higher than the other three groups with significant difference (P ＜ 0.05).There were no significant difference between G1,G2 and G3 in SvO2,Lac,positive vasoactive drugs、ventilation time and ICU time.All patients were alive.Conclusion Low reoxygenation concentration can reduce the reoxygenation injury of cyanotic congenital heart disease,though there may be some potential influence to cerebral oxygen metabolism.Further studies about oxygen supplymethodsare necessary in deep hypothermia and long-time CPB.