重症减压病血管内皮及凝血纤溶系统变化的实验研究

Change in vascular endothelium and blood coagulation and fibrinolysis system induced by severe decompression sickness in New Zealand rabbits

目的观察实验兔发生重症减压病过程中血管内皮及凝血纤溶系统相关指标的变化,分析重症减压病致死的可能机制。方法14只新西兰白兔,在0·55MPa下停留35min,再升至0·7MPa停留35min,于4min内匀速减压出舱。检测加压前、高压停留中、减压后兔血浆内皮素-1(ET-1)、血管性血友病因子(vWF)、纤维蛋白原(FIB)、D-二聚体(D-Dimer)、凝血因子Ⅷ(FⅧ)活性、纤溶酶原(PLG)、纤溶酶抑制物(PL-IN)、凝血酶原时间(PT)、部分活化凝血活酶时间(APTT)等指标。比较减压后存活动物与死亡动物以上指标变化的特点。结果8只兔于减压后30min内死亡,6只存活且观察24h后未遗留任何减压病症状。0·55MPa下停留30min后,兔血浆ET-1由加压前的1·33±0·33pg/ml升至2·74±0·87pg/ml;vWF活力由2·62±0·69%升至3·64±1·48%。与高压停留中比较,快速减压后死亡组兔FIB减少量为0·92±0·12g/L,D-Dimer减少量为55·63±12·12ng/ml,均明显大于存活组(P<0·01)。结论实验兔于高压停留阶段已有血管活性物质释放,快速减压后凝血激活程度更强,纤维蛋白原消耗更多,而继发性纤溶反应较弱的动物死亡的可能性更大。

Objective To observe the changes in the relative indexes of vascular endothelium, blood coagulation and fibrinolysis system of rabbits with experimental severe decompression sickness （DCS）, and to compare the above indexes of surviving rabbits with those of dead in order to analyze the mechanism of causes of death. Methods 14 rabbits were put into a decompression chamber. They stayed for 35 rnin under an atmospheric pressure of 0.55 MPa, followed by a pressure of 0.7MPa for 35min. Then they were subjected to a pressure of 0. 1MPa for 4 minutes. Blood samples were drawn before the compression, under high pressure, and after decompression to determine endothelin-1 （ET-1）, von Willebrand factor （vWF）, fibrinogen （FIB）, D-Dimer, blood coagulation factor Ⅷ（FⅧ）, plasminogen （PLG）, plasmin inhibitor （PL-IN）, prothrombin time （PT）, and activated partial thromboplastin time （APTT）. The changes of above parameters of surviving rabbits were compared with those of the dead. Results After rapid decompression, 8 rabbits died within 30 minutes, while the other 6 rabbits survived and all symptoms of decompression sickness disappeared 24 hours after decompression. The plasma level of ET-1 increased from 1.33±0.33pg/ml to 2.74±0.87pg/ml after a 30min stay under 0. 55MPa, while the activity of vWF increased from 2.62±0. 69% to 3. 64±1. 48%. Compared with the surviving rabbits, those dead rabbits showed significant reduction in FIB （0. 92±0. 12g/L） and D-Dimer （55. 63±12. 12ng/ml）, after rapid decompression. Conclusions There was a release of vasoactive substance in the blood of rabbits during the period when they stayed under high pressure. After rapid decompression, the most important difference between the survivors and the dead was that there were stronger coagulation activation, more consumption of FIB and weaker secondary fabrinolysis in the latter compared with the survivors.