Changes Of Coagulation Function After Traumatic Hemorrhagic Shock Porcine Model In Dry-heat Environment

Objective: To compare the changes of blood coagulation after traumatic hemorrhagic shock in dry-heat environment with in normothermic environment,and offer valuable references for clinical treatment.Methods: Forty landrace pigs were randomly assigned to four groups of ten animals each: traumatic hemorrhagic shock in dry-heat environment,sham operation in dry-heat environment,traumatic hemorrhagic shock in normothermic environment and sham operation in normothermic environment.During the experiment,the pigs in dry-heat environment groups were placed in The Simulated Climate Cabin for Special Environment of Northwest of China(temperature 40.5±0.5℃,relative humidity 10±2%).The traumatic hemorrhagic shock was to be modeled in pig only after 3 hours exposure to dry-heat environment.All procedures were done under general anesthesia using sevoflurane.The swines were hemorrhaged to an initial goal mean arterial pressure(MAP)of 45 ± 5 mm Hg and removal of 1/4 from the lower left lobe of liver causes Grade III hepatic injury.The pigs in normothermic environment groups were placed in a normal temperature environment during experiment.Animals in the sham operation groups underwent laparotomy only did not receive trauma and bled.Coagulation was assessed by Lactate(Lac),Platelet(PLT),prothrombin time(PT),Fibrinogen(FBG),D-dimer,and thrombelastography(TEG)from blood samples taken at before experimentation(baseline),after 3 hours exposure to dry-heat environment,just being shock(0H),0.5h after shock(0.5H),1h after shock(1H),2h after shock(2H)and 3h after shock(3H).Lung specimens were examined histopathological in the end of experiment.Results:(1)Compared with before experimentation,the initial clotting time(R)at 0.5H in dry-heat shock group and normothermic shock group were shortened to 2.8±0.4min and 2.6±0.4min(both P< 0.05),respectively;clot formation time(K)were shortened to 0.9±0.2min and 1.2±0.2min(both P<0.05);clotting rapidity(α)was increased to78.3±2.5° and 79.8±2.2°(P<0.05);maximum amplitude(MA)decreased to 71.1±1.5mm.These data suggested that dry-heat shock group and normothermic shock group were in hypercoagulable state at 0.5H.In dry-heat shock group at 3H,R time was prolonged to 6.2±0.9min,K time was prolonged to 2.3±0.3min,α angle decreased to 61.5±4°,in dry-heat shock group,MA increased to 62.2±1.8mm.There was statistically different either Within-group comparison or comparison between groups.In normothermic shock group did not change R time,K time,or α angle,but impaired clot strength.Compared with before experimentation value,MA at 3H in normothermic shock group decreased to 65±1.8mm(P<0.05)indicated that hypocoagulable state.These data suggested that more severe coagulation disorder in dry-heat shock group.(2)In dry-heat shock group at 3H,platelet counts fell to 323±17×103/μL,fibrinogen decrease to 111±10 mg/dl,D-dimer rise to 263±36μg/dl.There was statistically different either Within-group comparison or comparison between groups.These data indicated that decrease of substances necessary for clotting and large numbers of Microthrombi formation after traumatic hemorrhagic shock in dry-heat environment.(3)In this study,we neither observed significant changes of PT at each time point compared with corresponding before experimentation nor between the dry-heat shock group and other three groups.Conclusions: Traumatic hemorrhagic shock in dry-heat environment lead to more severe coagulation disorder than in normothermic environment.Dry-heat environment may results in more advanced magnitude of shock.In the consumptive coagulopathy state,After three hours of the traumatic hemorrhagic shock in dry-heat environment,disseminated intravascular coagulation was also detected.TEG may be of value in the management of patients who have had traumatic hemorrhagic shock in dry-heat environment.