摘要
目的 观察肺缺血前、后血液稀释对肺缺血再灌注(I/R)损伤的影响,探讨血液稀释对肺缺血再灌注损伤的干预作用及机制。方法 采用兔单肺原位缺血再灌注损伤模型,术中不同时点进行急性等容血液稀释。实验分四组:对照组(单纯开胸,C),缺血-再灌注组(I/R),缺血-稀释-再灌注组(IHR),稀释-缺血-再灌注组(HIR)。血液稀释时采用颈动脉放血,同时静脉补入等量低分子右旋糖酐。分别于肺缺血前、缺血1h、再灌注1h采血检测超氧化物歧化酶(SOD)、一氧化氮(NO),记录呼吸道峰压(Ppeak)。术毕测定血内丙二醛(MDA)、肺组织湿/干比值(W/D)及病理改变。结果 C组、IHR组和HIR组的W/D、MDA、P peak和肺组织炎性改变及肺水肿指标在术毕或缺血1h明显低于I/R组;而SOD却明显高于I/R组;HIR组P peak、术毕W/D、MDA低于IHR组,组织病理检查显示水肿及白细胞浸润程度比IHR组轻。结论 血液稀释对肺I/R损伤有预防、治疗作用;缺血前稀释血液效果更明显。适度的血液稀释对肺缺血再灌注损伤具有预防和治疗作用。
Objective To investigate the protective effect of acute normovolemic hemodilution on the lung against ischemia-reperfusion (I/R) injury.Methods Twenty-four rabbits of either sex weighing 2.0-2.5 kg were anesthetized with intravenous 3% pentobarbital 35 mg·kg-1 . The animals were tracheostomized and mechanically ventilated. Right common carotid artery was cannulated for MAP monitoring. The unilateral lung ischemia was produced by mass ligation of the hilum of the left lung with a rubber band and maintained for 1 h. The ligation was then released for 1 h reperfusion. Acute normovolemic hemodilution was accomplished in 20 min by removing blood from arterial cannula until Hct reached around 26% . The removed blood was replaced with dextran 40. The animals were randomly divided into 4 groups of 6 animals :(1) control group (C) ;(2) ischemia-reperfusion group (I/R); (3) ischemia-hemodilution-reperfusion group (IHR) and (4) hemodilution-ischemia-reperfusion group (HIR). In group 3 hemodilution was started at 35 min of ischemia and in group 4 hemodilution was accomplished before I/R. Blood samples were taken before ischemia (T0 ) , at the end of 1h ischemia (T1 ) and at the end of 1 h reperfusion (T2) for determination of plasma levels of SOD and NO. Peak airway pressure (Ppeak) was also recorded at T0 , T1 and T2. At the end of the experiment the lungs were removed for microscopic examination and determination of wet/dry lung weight ratio (W/D) . Blood level of malondialdehyde (MDA) was measured at the end of the experiment while the lungs were being removed.Results 1. Ppeak was gradually increasing during ischemia and reperfusion in all of the four groups. At T1 Ppeak was significantly higher in group 2 (I/R) and 3 (IHR) than that in control group. At T2 Ppeak was also significantly higher in group 4 (HIR) than that in control group but was significantly lower than that in group 3 (IHR). 2. There was no significant difference in plasma NO level among the four groups at T1 . But at T2 plasma NO level was significantly higher in IHR (group 3) and HIR (group 4) groups than that in I/R group (group 2) . 3. At T2 blood MDA level was significantly higher in I/R group than that in control group and HIR group (group 4), but there was no significant difference in MDA level between I/R group and IHR group (group 3). 4. The degree of lung edema and leukocyte infiltration was in the order of : group I/R > IHR > HIR > C. Conclusion Adequate hemodilution can attenuate the lung injury induced by I/R. The protective effect is better if hemodilution is performed before I/R.
出处
《中华麻醉学杂志》
CAS
CSCD
北大核心
2004年第1期40-43,共4页
Chinese Journal of Anesthesiology
