Kim W G, Lee B H, Seo J W
Department of Thoracic and Cardiovascular Surgery, Seoul National University College of Medicine and Clinical Research Center, Seoul National University Hospital, Korea.
Perfusion. 2001 May;16(3):207-14. doi: 10.1177/026765910101600306.
An experiment to study the role of contact-activation leukocyte sequestration in the formation of ischaemia-reperfusion injury (I-R injury) was carried out. The study was conducted using light and electron microscopic analyses in an ovine cardiopulmonary bypass (CPB) model using a membrane oxygenator. Five adult sheep were used in the study. The CPB circuitry consisted of a roller pump and a membrane oxygenator. During CPB, flow rates ranged from 50 to 60 ml/kg/min with mild hypothermia. The CPB time was fixed at 120 min. Ten minutes after the start of CPB, total CPB was established. Thereafter, total CPB was performed for 100 min, followed by another 10 min of partial CPB. Lung biopsy specimens for light and electron microscopy were obtained from the upper lobe of the right lung before CPB, 109 min after the start of CPB (just before reperfusion) and 30 min after weaning (after reperfusion). A portion of the lung biopsy specimen was taken for a water content measurement at the same time intervals. For measuring the left and right atrial leukocyte counts, blood samples were taken before thoracotomy, 5 and 109 min after the start of CPB, and 30 and 120 min after weaning. C3a was measured before thoracotomy, 109 minafter the start of CPB, and 30 and 120 min after weaning. Plasma malondialdehyde (MDA) was checked before thoracotomy, 109 min after the start of CPB and 30 min after weaning. On both light and electron microscopic examination, mild to moderate acute lung change was observed after ischaemia-reperfusion. Interstitial oedema, leakage of erythrocytes into the alveolar space and endothelial cell swelling were the main findings. However, few neutrophils were seen. Water content of the lung showed a slight increase after the start of CPB, but there was no statistical significance. Neither significant differences in the transpulmonary gradients of leukocytes nor a significant complement activation, expressed by C3a levels, was observed. The MDA level did not display a significant change related to lung reperfusion despite an increase in MDA after the start of CPB. These findings indicate that I-R injury during CPB may not be from complement-activation leukocyte sequestration, but from another source of oxygen free radicals related to CPB.
开展了一项实验，以研究接触激活白细胞隔离在缺血再灌注损伤（I-R损伤）形成中的作用。该研究在使用膜式氧合器的羊体外循环（CPB）模型中，通过光镜和电镜分析进行。研究中使用了5只成年绵羊。CPB回路由一个滚压泵和一个膜式氧合器组成。在CPB期间，流量范围为50至60毫升/千克/分钟，并伴有轻度低温。CPB时间固定为120分钟。CPB开始10分钟后，建立完全CPB。此后，进行100分钟的完全CPB，接着进行10分钟的部分CPB。在CPB前、CPB开始109分钟后（即将再灌注时）以及撤机后30分钟（再灌注后），从右肺上叶获取用于光镜和电镜检查的肺活检标本。在相同时间间隔取一部分肺活检标本进行含水量测量。为了测量左右心房白细胞计数，在开胸术前、CPB开始5分钟和109分钟后以及撤机后30分钟和120分钟采集血样。在开胸术前、CPB开始109分钟后以及撤机后30分钟和120分钟测量C3a。在开胸术前、CPB开始109分钟后以及撤机后30分钟检查血浆丙二醛（MDA）。在光镜和电镜检查中，缺血再灌注后均观察到轻度至中度的急性肺改变。间质水肿、红细胞漏入肺泡腔和内皮细胞肿胀是主要发现。然而，几乎未见中性粒细胞。CPB开始后肺含水量略有增加，但无统计学意义。未观察到白细胞跨肺梯度的显著差异，也未观察到以C3a水平表示的显著补体激活。尽管CPB开始后MDA有所增加，但MDA水平与肺再灌注无显著相关变化。这些发现表明，CPB期间的I-R损伤可能并非源于补体激活白细胞隔离，而是源于与CPB相关的另一种氧自由基来源。
