Zhu Zhong-qun, Su Zhao-kang, Zhu De-ming, Xu Zhi-wei, Yang Yan-min, Jiang Zhu-ming
Department of Pediatric Thoracic & Cardiovascular Surgery, Xinhua Hospital, Shanghai Children's Medical Center, Shanghai Second Medical University, Shanghai 200127, China.
Zhonghua Yi Xue Za Zhi. 2005 Mar 9;85(9):614-7.
To investigate the role of graded reoxygenation with cardiopulmonary bypass (CPB) in prevention of reoxygenation injury in children with cyanotic congenital heart defects, and to evaluate its safety.
Twenty pediatric patients with cyanotic congenital heart defect were randomly divided into 2 equal groups according to CPB methodology: group 1, undergoing routine hyperoxic CPB with CPB primed and initiated at FiO(2) of 1.0, and group 2 undergoing modified CPB with graded reoxygenation (CPB was primed and initiated at FiO(2) of 0.21 and the FiO(2) was increased slowly to 30% to 60% over the next 5 to 10 minutes). Serum troponin 1 (TnI), S100beta protein, and malondialdehyde (MDA) were measured before CPB, and 1 minute, 5 minutes, and 10 minutes after CPB. Near infrared spectroscopy (NIRS) was applied to evaluate the cerebral oxygenated hemoglobin (HbO(2)) and oxidized cytochrome aa3 (CytOx) and jugular venous lactate was measured during the reoxygenation period. Clinical indexes were observed.
Before CPB the TnI, S100beta, and MDA levels in these 2 groups were all normal without significant differences between them. After initiation of CPB the TnI, S100beta, and MDA levels in the two groups began to increase. The serum Tn1 levels 1 minute and 5 minutes after the initiation of CPB of the group 1 were significant lower than those of the group 2 (both P < 0.01). The serum S100beta levels 1, 5, and 10 minutes after the initiation of CPB in the group 2 were all lower than those of the group 1 and there were significant differences between these 2 group 5 and 10 minutes after (both P < 0.05). The serum MDA levels 1, 5, and 10 minutes of the group 1 were significantly higher than those of the group 2 (all P < 0.05). NIRS showed that HbO(2) decreased slightly because of hemodilution when CPB was begun, and then increased rapidly 2 minutes after the initiation of CPB; and CytOx decreased progressively during the reoxygenation period, however, without significant difference between these 2 groups. The serum lactate level was markedly increased 1 minute after the initiation of CPB and then gradually decreased through the reoxygenation period, however, without significant differences between these 2 groups. There was no significant difference between the two groups in clinical observation.
Not damaging the cerebral aerobic metabolism, graded reoxygenation with CPB can reduce the extent of reoxygenation injury of routine hyperoxic CPB and is an easy, effective, and safe CPB strategy.
探讨体外循环（CPB）下分级复氧在预防青紫型先天性心脏病患儿复氧损伤中的作用，并评估其安全性。
20例青紫型先天性心脏病患儿根据CPB方法随机分为两组，每组10例：第1组采用常规高氧CPB，CPB预充液及启动时FiO₂为1.0；第2组采用改良CPB分级复氧（CPB预充液及启动时FiO₂为0.21，在接下来5至10分钟内FiO₂缓慢升至30%至60%）。在CPB前、CPB开始后1分钟、5分钟及10分钟测定血清肌钙蛋白I（TnI）、S100β蛋白及丙二醛（MDA）。在复氧期应用近红外光谱（NIRS）评估脑氧合血红蛋白（HbO₂）及氧化型细胞色素aa₃（CytOx），并测定颈静脉乳酸。观察临床指标。
CPB前两组患儿TnI、S100β及MDA水平均正常，两组间无显著差异。CPB开始后两组TnI、S100β及MDA水平均开始升高。第1组CPB开始后1分钟及5分钟时血清TnI水平显著低于第2组（均P<0.01）。第2组CPB开始后1、5及10分钟时血清S100β水平均低于第1组，且在5分钟及10分钟后两组间差异有统计学意义（均P<0.05）。第1组CPB开始后1、5及10分钟时血清MDA水平显著高于第2组（均P<0.05）。NIRS显示CPB开始时因血液稀释HbO₂略有下降，CPB开始后2分钟迅速上升；复氧期CytOx逐渐下降，但两组间无显著差异。CPB开始后1分钟血清乳酸水平显著升高，随后在复氧期逐渐下降，但两组间无显著差异。两组临床观察指标无显著差异。
CPB分级复氧不损害脑有氧代谢，可减轻常规高氧CPB的复氧损伤程度，是一种简便、有效、安全的CPB策略。
