Longmore D B
Philos Trans R Soc Lond B Biol Sci. 1981 Aug 18;294(1072):399-412. doi: 10.1098/rstb.1981.0116.
The activation and disruption of platelets resulting from contact with bypass equipment is responsible for bleeding problems after open-heart surgery and for vascular injury leading to cerebral damage. This paper presents experimental and clinical evidence for the benefits of the preservation of platelets by prostacyclin (PGI2) during cardiopulmonary bypass operations. Work with dogs showed that PGI2 was more effective than heparin in maintaining the numbers and aggregability of the platelet population, but by far the most effective was a combination of the two agents. A subsequent double-blind clinical trial on 24 patients undergoing coronary vein grafts, in which the combination was compared with heparin alone, confirmed these findings in man. In the presence of PGI2, platelet numbers and aggregability were preserved, with a consequent reduction in blood loss. Significantly fewer reinforcing doses of heparin were required by the PGI2 group. The integrity of platelets in the presence of PGI2 was reflected by the lack of micro-aggregates and fibrin deposits on arterial line filters. In both the human and dog studies, PGI2 was shown, by the cultured foetal mouse heart test, to prevent the release of circulating cardiotoxic factors during bypass. The known vasodilator effect of PGI2 was observed but caused no clinical problems. An unexpected feature was the maintenance of perfusion pressure without the need for additional fluid. This may indicate that PGI2 reduces capillary permeability.
与体外循环设备接触导致的血小板激活和破坏是心脏直视手术后出血问题以及导致脑损伤的血管损伤的原因。本文提供了实验和临床证据，证明在体外循环手术期间通过前列环素（PGI2）保存血小板的益处。对狗的研究表明，PGI2在维持血小板数量和聚集性方面比肝素更有效，但到目前为止最有效的是两种药物的联合使用。随后对24名接受冠状动脉静脉移植的患者进行的双盲临床试验，将联合用药与单独使用肝素进行了比较，在人体中证实了这些发现。在PGI2存在的情况下，血小板数量和聚集性得以保留，从而减少了失血量。PGI2组所需的肝素强化剂量明显减少。动脉管路过滤器上缺乏微聚集体和纤维蛋白沉积反映了PGI2存在时血小板的完整性。在人体和狗的研究中，通过培养的胎鼠心脏试验表明，PGI2可防止体外循环期间循环心脏毒性因子的释放。观察到了PGI2已知的血管舒张作用，但未引起临床问题。一个意外的特点是无需额外补液即可维持灌注压力。这可能表明PGI2降低了毛细血管通透性。
