Change in vascular endothelium and blood coagulation and fibrinolysis system induced by severe decompression sickness in New Zealand rabbits / 解放军医学杂志

ABSTRACT

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 min 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.