血栓弹力图联合凝血指标评估脓毒症病情严重程度的临床价值分析

目的:探讨血栓弹力图(TEG)联合常规凝血指标评估脓毒症病情严重程度的临床价值。方法:选取2015年11月-2016年11月兰州军区兰州总医院重症医学科收治的重症感染患者97例为研究对象。依据脓毒症3.0将患者分为脓毒症(Sepsis)组(67例)、脓毒症休克(Septic Shock)组(30例)。完善相关检查后,检测和比较两组常规凝血功能指标(活化部分凝血活酶时间(APTT)、凝血酶原时间(PT)、纤维蛋白原(FIB)、D-二聚体(D-D)),描绘TEG(血凝时间(R)、血块成型时间(K)、α角、血块强度(MA))的差异及以上指标之间的相关性。结果:脓毒症休克组PT、APTT、FIB和D-D水平均较脓毒症组显著升高(P0.05),R、K均较脓毒症组显著缩短(P0.05),而α角、MA均较脓毒症组显著增大(P0.05)。TEG中R值、K值与PT、APTT呈正相关(r=0.439、0.267、0.379、0.136),与FIB、D-D呈负相关(r=-0.397、-0.671、-0.628、-0.534);α角、MA值与PT、APTT呈负相关(r=-0.127、-0.238、-0.459、-0.213),与FIB、D-D呈正相关(r=0.386、0.53、0.687、0.652)。结论:TEG联合凝血指标可较真实地判断脓毒症患者凝血纤溶状态,为脓毒症患者病情严重程度的判断提供更可靠的依据。     

The influence of porosity on the hemocompatibility of polyhedral oligomeric silsesquioxane poly (caprolactone-urea) urethane

BackgroundThe physio-chemical properties of blood contacting biomaterials play an important role in determining their hemocompatibility. It is shown in literature that surface roughness and porosity have significant effect on hemocompatibility. In this study, we use a biocompatible, low thrombogenic nanocomposite polymer called POSS-PCU to test this hypothesis: would porosity compromise the hemocompatibility of POSS-PCU. We compared the hemocompatibility of POSS-PCU films of various pore sizes with PTFE, which is a commercially available material used in most blood contacting devices.MethodsSterilized POSS-PCU films with different size pores were prepared as samples and porous PTFE film were selected as control. And all samples were subjected to SEM for topograpgy, mechanical test for characterization and hemocompatibility tests to evaluate contact activation, platelet adhesion and activation, as well as whole blood clotting response to the samples.ResultsWCA significantly increased with the pore size of POSS-PCU film, whereas both tensile stress and strain decreased significantly as the sizes of pores increased. However, when compared to PTFE film with same size pores, POSS-PCU films showed both higher tensile stress and strain. Pore size had little impact over POSS-PCU's surface chemistry groups as tested by FTIR analysis. Contact activation and platelet adhesion essay also showed no significant difference between different POSS-PCU samples. However, in whole blood reactions, POSS-PCU with pores size around 2–5 μm showed higher BCI than plain films and those with pores size around 35–45 μm. POSS-PCU showed lower thrombogencity and higher hemocompatibility comparing with porous PTFE on the aspects of platelet activation, adhesion and whole blood reaction.Summary and conclusionsPOSS-PCU polymer films as a biomaterial in chronic blood contacting implants show significant lower thrombogencity and higher hemocompatibility than porous PTFE film. It is desirable as a coating or covering material in small diameter stents for treating cardiovascular diseases, cerebral vascular diseases and peripheral arterial diseases.