血栓弹力图在妊娠合并血小板减少症患者中的应用

目的探讨血栓弹力图(thromboelastography,TEG)在妊娠合并血小板减少症患者(PAT)中的应用。方法收集我院2016年4月～2019年3月确诊的60例妊娠合并血小板减少症患者,按照1∶1比例配对法分为两组,对照组30例,行常规凝血功能检测;观察组30例,进行常规凝血功能检测及血栓弹力图检测评估,分析两组的分娩情况、术中术后出血情况及实验室指标检测结果。结果两组ALT、AST、PT、APTT、TT、FIB无明显差异(P0.05),观察组阴道分娩率高于对照组、术中出血量高于对照组(P0.05),但两组的术后出血量及产后大出血发生率无差异(P0.05)。结论血栓弹力图用于PAT患者凝血的监测,可评估出血风险,为分娩方式的选择提供指导依据。     

Association of hemodilution and blood pressure in uncontrolled bleeding

Background

Hemodynamic status and coagulation capacity affect blood loss after injury. The most advantageous fluid and blood pressure to optimize resuscitation and minimize perturbation of coagulation are unclear. We investigated interactions of isovolumic hemodilution on hemodynamics, coagulation, and blood loss after injury.

Methods

Twenty-five male rats were randomized into three groups (Whole Blood Uncontrolled Blood Pressure [WBU], n = 7; Lactated Ringers Uncontrolled Blood Pressure [LRU], n = 10; Whole Blood Controlled Blood Pressure [WBC], n = 8) with isovolumic hemodilution of 50% blood volume, with and without control of pre-injury blood pressure. All rats underwent uniform grade IV liver injury 30 min after serial exchanges. Post-injury blood loss and coagulation function were measured.

Results

Dilution occurred, determined by hematocrit, with LRU having a greater reduction. Pre-injury mean arterial pressure (MAP) decreased compared with baseline (98 ± 7 mmHg) with LRU (62 ± 14 mmHg) and WBC (61 ± 10 mmHg), resulting in WBU (101 ± 13 mmHg) being significantly higher and not changed from baseline. Post-injury, MAP decreased from pre-injury, with LRU significantly lower than the other two groups. No differences were observed in prothrombin time/international normalized ratio or thromboelastography. Bleed volume was significantly different between groups: WBU < WBC < LRU and associated with the pre-injury MAP. Controlling baseline MAP, dilution with Lactated Ringers (LR) resulted in greater blood loss than whole blood (3.0 ± 0.4 versus 1.9 ± 0.3 mL).

Conclusions

In this rat model of liver injury, blood loss was associated with baseline MAP and type of fluid used for dilution. Hemodilution with LR did not produce coagulopathy based on laboratory values. When controlling baseline MAP, dilution with LR increased bleeding, confirming a functional coagulopathic state.     

血清D-二聚体、纤维蛋白原检测联合血栓弹力图对急性心肌梗死预后的评估价值

目的 探讨血清D-二聚体（D-D）、纤维蛋白原（Fib）检测联合血栓弹力图（TEG）对急性心肌梗死（AMI）预后的评估价值。方法 选取2018年8月～2021年2月我院收治的AMI患者126例,所有患者均接受经皮冠状动脉介入（PCI）治疗,根据患者随访期间是否发生主要心血管不良事件（MACE）将患者分为预后不良组（n=41）和预后良好组（n=85）。比较两组患者的一般临床资料、血清D-D、Fib和TEG指标,分析D-D、Fib和TEG指标的相关性,采用受试者工作特征曲线（ROC）分析D-D、Fib和TEG指标对AMI患者预后的评估价值。结果 预后不良组患者的收缩压（SBP）、舒张压（DBP）水平明显小于预后良好组,心率（HR）明显高于预后良好组（均P＜0.05）;预后不良组患者的血清D-D、Fib水平高于预后良好组,两组患者的TEG指标凝血反应时间（R）、凝血形成速率（Angle角）、血栓最大振幅值（MA）和凝血综合指数（CI）比较,差异有统计学意义（均P＜0.05）。Logistic回归分析结果显示,血清D-D、Fib、R、Angle角、MA和CI是影响患者预后的独立危险因素（P＜0.05）;相关性分析结果显示,D-D与R呈负相关,与Angle角、MA值和CI均呈正相关（P＜0.05）;Fib与MA值、CI呈正相关（P＜0.05）。ROC曲线分析结果显示,D-D、Fib、R、Angle角、MA值和CI评估AMI患者预后的AUC值分别为0.838、0.824、0.791、0.780、0.808、0.677,联合检测的AUC值为0.863,对AMI患者预后的评估有统计学意义（均P＜0.05）。结论 血清D-D、Fib和TEG指标的变化与AMI患者PCI术后MACE发生存在相关性,对AMI患者预后不良的评估具有一定临床价值。     

Perioperative therapeutic plasma exchange in a patient with rare Factor XIII inhibitor

IntroductionFactor XIII deficiency is a rare bleeding disorder which could be severe if inherited or less severe if acquired. We report a case of acquired Factor XIII inhibitor in a 75-year-old male with a suspicious left renal mass treated perioperatively with therapeutic plasma exchange (TPE).Patient and methodTo perform kidney biopsy and ablation of the renal mass, six daily TPE treatments were performed before and after biopsy to minimize bleeding risk because the patient did not respond to drug therapy. Both thromboelastography (TEG) and laboratory-based coagulation tests were performed to assess coagulation status prior to and after TPE.ResultsThe biopsy indicated oncocytoma which was removed by surgical procedure. Factor XIII activity remained below 15 % throughout TPE treatments, but Factor XIII inhibitor titer reduced from initial positive value of 1:40 to negative following the third TPE and remained negative through the sixth TPE. Unfortunately, the inhibitor titer was positive at 1:20 in the fifth month and 1:5 in the sixth month during follow-up.ConclusionsTPE is useful in removing XIII inhibitory factor, but the effects are only short term.     

血栓弹力图检测在指导心脏术后患儿成分输血中的应用价值

目的 探讨血栓弹力图(TEG)检测在指导心脏术后患儿成分输血中的应用价值.方法 选择心脏术后患儿103例,均在输血前检测TEG,根据R值、K值及MA值分别将患儿分为R值正常组(R≤10 min)85例及R值延长组(R>10 min)18例;K值正常组(K≤3 min)47例及K值延长组(K>3 min)56例;MA值正常组(MA≥50 mm)42例及MA值降低组(MA<50 mm)61例,记录其术后血浆和PLT的输注情况,比较组间术后输血情况以及输血前后相应的参数值.结果 R值延长组、K值延长组术后输注血浆者比例及血浆输注量分别高于R值正常组、K值正常组(P<0.05);R值延长组、K值延长组输注血浆后相应参数较前缩短,而R值正常组、K值正常组输注血浆前后相应参数无明显变化(P>0.05).MA值降低组术后输注PLT者比例及PLT输注量均高于或多于MA值正常组(P<0.05),但两组术后输注血浆者比例及血浆输注量比较差异均无统计学意义(P>0.05);MA减低组输注PLT后MA值较前升高(P<0.05),而MA正常组输注PLT前后MA值无明显变化(P>0.05).结论 TEG的R值、K值和MA值对心脏术后患儿成分输血具有指导意义.     

Recombinant factor VIIa reduces bleeding in severely thrombocytopenic rabbits

Severe thrombocytopenia is a common complication to intensive chemotherapeutic regimens. For bleeding episodes associated with severe thrombocytopenia, the current standard treatment is platelet transfusion. However, due to several transfusion complications such as transfusion-transmitted diseases, platelet refractoriness and immunomodulation, as well as increasing problems with sufficient supply of platelet products, it is imperative to search for alternatives to platelet transfusion. To test the efficacy of recombinant activated human coagulation factor VII (rFVIIa, NovoSeven) in thrombocytopenia, a preclinical study was conducted in thrombocytopenic rabbits. Thrombocytopenia was induced by a combination of gamma-irradiation and the use of platelet antibodies, and the effect of rFVIIa on nail cuticle bleeding was determined. Administration of rFVIIa at 2 mg/kg significantly shortened the prolonged bleeding time in thrombocytopenic animals (rFVIIa vs. control, median 23 min 41 s vs. 60 min, p=0.016) as well as significantly reducing the blood loss (rFVIIa vs. control, median: 8.8 vs. 12.2 nmol hemoglobin/ml, p=0.016). This effect was also reflected by a significant reduction of the prothrombin time, activated partial thromboplastin time, as well as improvement in clotting parameters in an in vitro thromboelastography thrombocytopenia model. Histopathological evaluation of kidney biopsies for the presence of micro thrombi did not reveal evidence of prothrombotic effects of rFVIIa in this model. These data demonstrate the haemostatic efficacy of rFVIIa in a rabbit model of severe thrombocytopenia. Clinical trials will be needed to further explore the potential of NovoSeven as a haemostatic agent in thrombocytopenic patients.     

Can Thromboelastography performed on kaolin-activated citrated samples from critically ill patients provide stable and consistent parameters?

Thromboelastography (TEG^®) is a potentially useful tool but analysis within 4-6 min of collection imposes limitations on its use and access. The use of citrate blood tubes potentially increases the time frame for processing specimens. There is, however, limited research on the stability of citrate specimens, timing of processing and the accuracy of TEG^® results. The purpose of this study was to examine the effects of early and delayed processing on TEG^® parameters using kaolin-activated citrated blood samples in the intensive care population. TEG^® analysis was performed on 61 patients. Blood was collected into two 3.2% sodium citrate (0.105 m ) tubes. Kaolin-activated samples were analysed at 15, 30 and 120 min postcollection. TEG^® parameters analysed included reaction time (R), clot formation time (K), alpha angle (α), maximum amplitude, LY30, the coagulation index, time to maximum rate of thrombus generation, maximum rate of thrombus generation and total thrombus generation. Sixty-one critically ill patients were included. The results of the anova showed that time from collection was significantly associated with the TEG^® results (P < 0.05). On comparison of individual outcome variables, this difference in most cases was due to changes over time from 30 to 120 min. Furthermore, progressive changes in TEG^® parameters such as decreasing R were suggestive of a trend toward hypercoagulability of the specimens. Processing of kaolin-activated citrate TEG^® specimens can begin as early as 15 min postvenipuncture. However, delaying processing by more than 30 min leads to a significant change in results.