体外循环中梯度控制氧分压对紫绀型先天性心脏病心肌保护的影响

1、体外循环中梯度控制氧分压对紫绀型先天性心脏病心肌保护的影响         10-01-29 11:13:00     编辑：studa20                      作者：陈萍，黄劲松，郭阳娇，宋兴荣，黄克力【摘要】  目的 探讨体外循环(C

2、PB)中梯度控制动脉氧分压(PaO2)对紫绀型先天性心脏病心肌保护的影响。方法 3岁以下经皮血氧饱和度<85%、行根治术的法洛四联症患儿90例，随机分为三组：实验1组(G1组，n=30)以接近患儿术前水平的低氧分压启动CPB并控制CPB中血流复温前的PaO2130 mmHg，CPB血流复温后使PaO2逐渐升至250300 mmHg;实验2组(G2组，n=30)CPB中PaO2在250300 mmHg启动CPB，血流复温后使PaO2逐渐升至450500 mmHg;对照组(G3组，n=30)CPB中PO2始终控制在450500 mmHg。观察心肌生化改变：于CPB前、CPB 10 min、升

3、主动脉开放(CCR)10 min、术后6 h、24 h抽外周血检测心肌酶CKMB、LDH活性及cTnI浓度。结果 CKMB：CPB前及CPB 10 min 三组间无差异;CCR 10 min、术后6 h及24 h G1组显著低于G3组(P<0.01);CCR 10 min G2组显著低于G3组(P<0.05)。 LDH：CPB前及CPB 10 min 三组间无差异;CCR 10 min、术后6 h 和24 hG1组显著低于G3组(P<0.01或P<0.05)。 cTnI：CPB前及CPB 10 min 三组间无差异;CCR 10 min、术后6 h、术后24 h G1组

4、显著低于G3组(P<0.01);术后6 h G2组cTnI也显著低于G3组(P<0.05)。结论 对于紫绀型先天性心脏病，CPB中PaO2控制在G1组的低水平能减少CKMB、LDH活性及cTnI的释放，改善心肌保护效果。 【关键词】  紫绀;先天性心脏病;体外循环;氧分压Abstract: OBJECTIVE To evaluate the effects of arterial oxygen partial pressure (PaO2) at the beginning and during cardiopulmonary bypass (CPB) on myocar

5、dial injury of cyanotic congenital heart diseas.METHODS 90 Children diagnosed Tetrallogy of Fallot (TOF) under 3 years of age with SpO2<85% underwent one stage repairing operations were divided into 3 groups: G1(n=30), experimental group 1, PaO2 at the beginning and during CPB was maintained belo

6、w 130 mmHg before CPB rewarming phase; G2(n=30), experimental group 2, PaO2 at the beginning and during CPB was controlled between 250-300 mmHg before CPB rewarming phase; G3(n=30), control group, PaO2 during CPB was maintained between 450-500 mmHg. Myocardial enzymes and cTnI were measured before C

7、PB, 10 min after CPB, 10 min after cross clamp releasing (CCR), 6 hrs and 24 hrs post operation with peripheral blood samples.RESULTS CKMB,LDH and cTnI had no significantly different between 3 groups preoperatively and 10 min after CPB among 3 group. At 10 min after CCR, 6 hrs and 24 hrs post operat

8、ion, KMB, LDH and cTnI in G1 were significantly lower than that in G3( P<0.01 or P<0.05). At 24 hrs post operation, also cTnI in G1 was significantly lower than that in G2(P<0.05). At 10min after CCR, CKMB in G2 was significantly lower than that in G3 (P<0.05). At 6hrs post operation, cT

9、nI in G2 was significantly lower than that in G3 (P<0.05).CONCLUSION During CPB controlling PaO2 to a preoperative low level would reduce releasing enzymes of myocardial and cTnI in cyanotic congenital heart disease.Key words： Cyanotic; Congenital heart disease;Cardiopulmonary bypass;Oxygen parti

10、al pressure紫绀型先天性心脏病(cyanotic congenital heart disease,CCHD)手术后低心排出量综合征仍是术后主要的并发症及死亡原因。有学者认为这与体外循环(cardiopulmonary bypass,CPB)中长期缺氧的心脏接受突然、大量的氧导致的再氧合损伤有关1。我们选择CCHD患儿来研究CPB中控制动脉氧分压(PaO2)对心肌酶及心肌肌钙蛋白I(cTnI)的影响。1 临床资料与方法1.1 病例的选择与分组 选择3岁以下、经皮血氧饱和度 (SpO2)<85%、行根治术的法洛四联症(tetralogy of Fallot,TOF)患儿90例，随

11、机分为三组：实验1组(G1组，n=30)以接近患儿术前水平的低氧分压启动CPB;实验2组(G2组，n=30)启动CPB时PaO2在250300 mmHg;对照组(G3组，n=30)CPB中PaO2始终控制在450500 mmHg。分组及临床资料见表1。1.2 CPB的建立及管理 气管插管，静吸复合麻醉。正中开胸行主动脉及上、下腔静脉插管建立CPB。采用Stockert 人工心肺机，Dideco 901或902膜式氧合器。预充液为：勃脉力A 200500 ml，20%白蛋白50 ml，红细胞悬液01.5 U，肝素1520 mg，甲泼尼龙2030 mg/kg等。CPB血流降温，阻断升主动脉(aor

12、tic cross clamp,ACC)，主动脉根部插针一次性顺行灌注冷改良St.Thomas晶体停搏液20 ml/kg。CPB中鼻咽温降至2225。开放升主动脉(cross clamp releasing,CCR)后并行循环时间为ACC时间的1/41/3，然后撤离CPB。1.3 PaO2的控制 采用SECHRIST空氧混合器、通过调节吸氧浓度(FiO2)来调节PaO2，应用TERUMO公司CDI 500行持续监测PaO2。G1组启动CPB时PaO2接近患儿麻醉前动脉血气分析的PaO2水平，在4080 mmHg，随着CPB的进行逐渐增加FiO2，至CPB 15 min PaO2上升到130 mmHg，并维持一段时间。在CPB开始血流复温时增加FiO2，使PaO2逐渐升至250300 mmHg至CPB结束。G2组启动CPB时PaO2在250300 mmHg，血流复温后使PaO2逐渐升至450500 mmHg至CPB结束。G3 组启动CPB及CPB整个过程中PaO2始终控制在450500 mmHg。1.4 观察指标 于CPB前(T1)、CPB 10 min(T2)、CCR后10 min(T3)、术后6 h(T4)、术后24 h(T5)抽外周血检测心肌肌酸激酶同工酶