Heparin resistance in severe thermal injury:a prospective cohort study  

作　　者：Liam D Cato Benjamin Bailiff Joshua Price Christos Ermogeneous Jon Hazeldine William Lester Gillian Lowe Christopher Wearn Jonathan RB Bishop Janet M Lord Naiem Moiemen Paul Harrison 

机构地区：[1]Scar Free Foundation Birmingham Centre for Burns Research,University Hospitals Birmingham Foundation Trust,Queen Elizabeth Hospital Birmingham,Mindelsohn Way,Birmingham,B152WB,UK [2]Department of Haematology,University Hospitals Birmingham Foundation Trust,MindelsohnWay,Birmingham,B152WB,UK [3]Institute of Inflammation and Ageing,University of Birmingham,Birmingham,B152TT,UK [4]NIHR Surgical Reconstruction and Microbiology Research Centre,University Hospitals Birmingham Foundation Trust,Mindelsohn Way,Birmingham,B152WB,UK

出　　处：《Burns & Trauma》2021年第1期157-169,共13页烧伤与创伤（英文）

基　　金：funded by the Scar Free Foundation and National Institute for Health Research Surgical Reconstruction and Microbiology Research Centre,British Society of Haematology and Royal College of Surgeons.

摘　　要：Background:Low molecular-weight heparin(LMWH)is routinely administered to burn patients for thromboprophylaxis.Some studies have reported heparin resistance,yet the mechanism(s)and prevalence have not been systematically studied.We hypothesized that nucleosomes,composed of histone structures with associated DNA released from injured tissue and activated immune cells in the form of neutrophil extracellular traps(NETs or NETosis),neutralize LMWH resulting in suboptimal anticoagulation,assessed by reduction in anti-factor Xa activity.Methods:Blood was sampled from>15%total body surface area(TBSA)burn patients receiving LMWH on days 5,10 and 14.Peak anti-factor Xa(AFXa)activity,anti-thrombin(ATIII)activity,cellfree DNA(cfDNA)levels and nucleosome levels were measured.Mixed effects regression was adjusted for multiple confounders,including injury severity and ATIII activity,and was used to test the association between nucleosomes and AFXa.Results:A total of 30 patients with severe burns were included.Mean TBSA 43%(SD 17).Twentythree(77%)patients were affected by heparin resistance(defined by AFXa activity<0.2 IU/mL).Mean peak AFXa activity across samples was 0.18 IU/mL(SD 0.11).Mean ATIII was 81.9%activity(SD 20.4).Samples taken at higher LWMH doses were found to have significantly increased AFXa activity,though the effect was not observed at all doses,at 8000 IU no samples were heparin resistant.Nucleosome levels were negatively correlated with AFXa(r=−0.29,p=0.050)consistent with the hypothesis.The final model,with peak AFXa as the response variable,was adjusted for nucleosome levels(p=0.0453),ATIII activity(p=0.0053),LMWH dose pre-sample(p=0.0049),drug given(enoxaparin or tinzaparin)(p=0.03),and other confounders including severity of injury,age,gender,time point of sample.Conclusions:Heparin resistance is a prevalent issue in severe burns.Nucleosome levels were increased post-burn,and showed an inverse association with AFXa consistent with the hypothesis that they may interfere with the anticoagulant effect of h

关 键 词：BURN Heparin resistance Low molecular-weight heparin NUCLEOSOMES Neutrophil extracellular traps Factor-Xa THROMBOSIS ENOXAPARIN NETosis 

分 类 号：R57[医药卫生—消化系统]