活化部分凝血活酶时间标准化问题的探讨

目的探讨活化部分凝血活酶时间(APTT)的标准化问题. 方法采用6种市售进口试剂检测不同水平凝血因子Ⅷ、Ⅸ、Ⅺ、ⅩⅡ及不同肝素水平血浆的APTT. 结果不同APTT试剂对含不同水平凝血因子血浆及肝素的敏感度不同.APTT的结果若以秒表示,同组标本不同试剂的结果有显著的差异.若以比值报告,结果无显著性差异. 结论不同的检测目的宜选用不同APTT试剂;测定结果以APTT比值形式报告较好.     

活化部分凝血活酶时间检测结果常见的误差原因分析

活化部分凝血活酶时间 (APTT)是内源凝血系统的筛选试验 ,其检测方法一般有手工法和仪器法两种 ,试剂为活化部分凝血活酶和氯化钙。在临床中 ,影响其检测结果的因素很多 ,现将使结果出现常见误差的原因总结如下。1　试剂因素1 .1　试剂盒质量　试剂质量是获得检测结果可靠性的先决条件。现在生产活化部分凝血活酶试剂盒的厂家较多 ,不同厂家其试剂盒组成不同 ,质量也有所不同。在选择试剂盒时 ,一方面要根据所用检测仪器 (例如光电检测法的血凝仪不宜选用透光度差的试剂 ) ;另一方面要根据不同检测目的选择不同的试剂 ,因为不同试剂盒对凝…     

活化部分凝血活酶时间标准化问题的探讨

目的 探讨活化部分凝血活酶时间（ＡＰＴＴ）的标准问题。方法 采用６种市售进口试剂检测不同水平凝血因子Ⅷ、Ⅸ、Ⅺ、Ⅻ及不同肝素水平血浆的ＡＰＴＴ。结果 不同ＡＰＴＴ试剂对含不同水平凝血因子血浆及肝素的敏感度不同。ＡＰＴＴ的结果若以秒表示,同组标本不同试剂的结果有显著的差异。若以比值报告,结果无显著性差异。结论 不同的检测目的宜选用不同ＡＰＴＴ试剂;测定结果以ＡＰＴＴ比值形式报告较好。     

贫血对凝血酶原时间和活化部分凝血活酶时间检测结果的影响研究

目的设计对照试验,研究贫血对凝血酶原时间(PT)和活化部分凝血活酶时间(APTT)检测结果的影响。方法选择从2014年5月至2015年5月在该院接受检查的126例贫血患者作为研究对象,每位患者均采集2管血,常规组的一管以抗凝剂与全血体积比1∶9为标准进行采血,试验组标本按公式[抗凝剂体积(mL)=0.1 85×采血量×(1-HCT)]将校正采血量计算出,以校正采血量为标准进行采血,并对其PT和APTT值进行检测,将不同HCT时PT与APTT值的差异进行对比。结果HCT≥0.25时,两组间PT、APTT值比较差异无统计学意义(P0.05);HCT0.25时,试验组PT、APTT值显著低于常规组,差异有统计学意义(P0.05)。结论 HCT0.25的严重贫血患者,采用常规采血方式会使PT和APTT的检测数据偏小,为提高PT和APTT检测数据的精确度应校准采血量。     

溶血标本对活化部分凝血活酶时间测定的影响

目的探讨溶血标本对活化部分凝血活酶时间测定的影响。方法对64例患者血样在溶血前后的标本进行对照实验。结果两组标本结果经统计学分析,差异有统计学意义(P0.01)。结论溶血标本对活化部分凝血活酶时间实验结果有影响。     

凝血酶原时间测定和活化部分凝血活酶时间测定的临床价值分析

目的比较分析凝血酶原时间（PT）和活化部分凝血活酶时间（APTT）在一些疾病中的价值。方法采用法国生产的STAGO（思达高）全自动血凝仪进行测定376例各种疾病和健康正常成人50例血液胛、APTT。结果血液病、弥散性血管内凝血（DIC）、肝癌、肝病及高血压患者PT及APIT二者均延长比率最高。结论对血液病、DIC、肝癌、肝病及高血压患者选择测定PT、APTT有较大临床价值。     

活化部分凝血活酶时间标准化报告方式的可行性探讨

目的探讨活化部分凝血活酶时间(APTT)实验测定值比率报告的临床价值,从而提高APTT实验报告的可比性。方法采用德国TECO公司和上海太阳生物技术公司的2种APTT试剂在德国AMAX190全自动凝血分析仪中分别检测正常对照组和患者组的APTT测定值(S)并计算出其比率。结果 2种APTT试剂检测2组研究对象的APTT测定值(S),差异有统计学意义(P0.05),但2种试剂的APTT测定值比率,差异无统计学意义(P0.05)。结论 APTT测定值比率的报告方式[APTT测定值比率=患者APTT测定值(S)/正常参比血浆APTT测定值(S)]可以减少测定值(S)结果的差异,提高结果的可比性。     

凝血酶原时间和活化部分凝血活酶时间三种质控物的比较

质量控制是保证试验结果准确的重要措施 ,其中合格的质控物是质量控制的关键因素之一。目前 ,凝血酶原时间 ( PT)和活化部分凝血活酶时间( APTT)试验的质控物主要依赖进口 ,其价格较贵。我们通过对两种自制质控物 (混合血浆、单一血浆 )与进口质控物比较 ,结果混合血浆与进口质控物无明显差异 ,且制备成本低廉 ,便于推广应用。一、材料和方法1 .仪器　德国 BE公司 Compact X全自动血凝仪。2 .试剂　美国 Biopool公司 PT试剂盒 (批号 :2 51 L0 1 )、APTT- EA试剂盒 (批号 :42 0 K0 3)、正常质控物 ( NCCP,批号 :1 0 0 L0 2 )、异…     

杀鼠药大隆中毒与血浆凝血酶原时间、活化部分凝血活酶时间

我院于 2 0 0 1年 6月接诊了一起集体中毒病例 ,病人临床表现有恶心、呕吐、腹泻、急性腹痛、头昏等临床症状。实验室检查发现病人凝血指标延长 ,少数病人镜下血尿、粪便隐血阳性 ,反映出较典型的抗凝血类灭鼠剂中毒症状 ,病人经洗胃后立即用维生素Ｋ1、辅酶Ａ、肌苷、三磷酸腺苷等治疗 ,后经防疫站检查证实为大隆 (第二代抗凝血杀鼠药 )中毒。患者经我院临床诊治 1个月左右均顺利康复。现将中毒病人各阶段血凝指标的监测结果报道如下。1　材料和方法1.1　材料1.1.1　标本来源　收治入院的杀鼠药大隆中毒病人 93例 ,其中男性 74例 ,女性 19…     

糖化血红蛋白与活化部分凝血活酶时间的相关性研究

目的 研究糖化血红蛋白(HbA1c)与活化部分凝血活酶时间的相关性,评价2型糖尿病的凝血功能.方法 收集符合标准的病例200例,HbA1c<6.2% 121例,HbA1c>6.2% 79例,分别进行凝血酶原时间(PT)、部分凝血活酶时间(APTT)、纤维蛋白原(FIB)、凝血酶时间(TT)项目的 测试.结果 组内比较:HbA1c <6.2%组,FIB升高差异有统计学意义(P<0.01),说明控制较好的糖尿病患者多伴有FIB升高;HbA1c >6.2 g/L组,APTT缩短,FIB升高差异有统计学意义(P<0.01);说明控制较差的患者常伴有APTT缩短,FIB升高.两组间APTT缩短差异有统计学意义,说明APTT缩短与HbA1c呈正相关.结论 APTT可作为2型糖尿病凝血功能的评价指标.     

Thrombin generation for the control of heparin treatment, comparison with the activated partial thromboplastin time.

Heparin can be quantified with antifactor Xa and IIa tests (aXa, aIIa) but the anticoagulant power of heparin depends upon plasma properties as well as upon heparin concentrations and thus differs between subjects. Measuring the effect, as with the activated partial thromboplastin time (APTT) therefore is clinically more relevant. Here we investigate the use of the endogenous thrombin potential (ETP) for this purpose. In 12 volunteers 9000 IU of four heparins of different mol. wt distributions were injected. Samples were taken at 11 time points between 0 and 24 h. With the exception of the 0 and 24-h time points, heparin could be demonstrated by its aIIa and aXa activity in virtually all samples. The APTT showed the effect of this heparin in 34% of the samples; the ETP in 80%. This is partly due to the wide margins of the normal values, caused by large interindividual variation [coefficient of variation (CV) approximately 12% for the APTT, approximately 17% for the ETP]. The intraindividual variation is much smaller (CV approximately 4% for the APTT, approximately 5% for the ETP). Relative to the baseline value of the individual, the heparin effect was recognized by the APTT in 55% of the cases and by the ETP in 98%. There were no large differences between the different types of heparin.     

激活剂对检测活化部分凝血活酶时间的差异性研究

目的探讨不同激活剂作为活化部分凝血活酶时间(APTT)检测试剂时对APTT测定结果的影响。方法用鞣花酸和白陶土两种激活剂分别在LG-PABER-1型血凝分析仪和Sysmex CA-500全自动血凝分析仪上进行APTT检测,并在血浆中分别加入肝素钠和乏因子血浆进行APTT检测。运用t检验和方差分析对检测结果进行统计学分析。结果⑴在LG血凝仪上运用鞣花酸和白陶土作为不同激活剂,对37例临床标本进行APTT测定结果显示:白陶土作为激活剂测得的结果高于鞣花酸测得的结果(P0.05)。⑵同一批号的鞣花酸作为激活剂在Sysmex血凝仪和LG血凝仪上分别对40例临床标本进行APTT测定,结果显示:LG血凝仪上测得的结果高于Sysmex血凝仪测得的结果(P0.05)。⑶鞣花酸和白陶土作为不同激活剂对含有不同浓度肝素钠的血浆35例进行APTT测定结果显示:随着肝素钠浓度的增加,两种激活剂的APTT结果明显延长,与未加肝素钠组比较有显著差异(P0.05)。且鞣花酸组变化比白陶土组变化更明显。⑷运用鞣花酸和白陶土作为不同激活剂,对加入不同乏凝血因子的血浆后的血浆33例进行APTT测定显示:随着血浆中加入乏因子血浆的比例增多,两种激活剂的APTT结果延长也明显,与未加乏因子血浆的血浆的APTT比较有显著差异(P0.05)。且白陶土组变化比鞣花酸组更明显。结论不同激活剂APTT检测结果存在差异,且对肝素或乏因子血浆的敏感性存在差异;同一激活剂在不同仪器上APTT检测结果存在差异。建议不同的实验室应建立自己的参考范围。     

Correlation between activated clotting time and activated partial thromboplastin times

OBJECTIVE: To evaluate the correlation between clotting time tests and heparin concentration, the correlation between activated clotting time (ACT) and activated partial thromboplastin time (aPTT) results, and to compare the clinical decisions based on ACT results with those based on aPTT results. METHODS: Retrospective evaluation of a large database containing heparin concentrations, ACT results (1 device), and aPTT results (3 different instruments: 2 bedside, 1 laboratory-based). Correlations between heparin concentrations and clotting time tests and between ACT results and aPTT results were determined. Clinical decisions regarding heparin dosage adjustments based on ACT results were compared with those based on aPTT results. RESULTS: Correlations between clotting time tests and heparin concentrations were r = 0.72 for ACT and r = 0.74-0.86 for the aPTT instruments. The laboratory-based aPTT had the highest correlation to heparin concentrations. The correlation between ACT and aPTT results ranged from r = 0.64-0.67. Heparin dosage adjustment decisions based on ACT results agreed with decisions based on aPTT results 59-63% of the time. CONCLUSIONS: The laboratory-based aPTT has a stronger correlation to heparin concentration than the bedside-based aPTT and ACT. The correlation between ACT and aPTT was similar among 3 different aPTT instruments. Decisions to adjust heparin therapy based on ACT results differed from decisions based on aPTT results more than one-third of the time.     

How to interpret and pursue an abnormal prothrombin time, activated partial thromboplastin time, and bleeding time in adults

The prothrombin time (PT) and activated partial thromboplastin time (APTT) are among the most commonly ordered coagulation tests. In 2005, more than 140,000 PT and more than 95,000 APTT tests were performed at Mayo Clinic. The most common indications for ordering these tests include anticoagulant monitoring, initial evaluation of hemorrhage, and, although not generally indicated, routine preoperative screening. In addition, the bleeding time (BT) test, which is infrequently performed, is still available in certain institutions. Abnormal results from these tests (prolonged PT, APTT, and BT), especially from tests conducted for initial evaluation of hemorrhage or for preoperative screening, may pose a diagnostic dilemma to the nonhematologist. We review the essential factors affecting test results; provide a practical approach to the evaluation of a prolonged PT, APTT, and BT; and offer suggestions on which reflexive tests are appropriate and when to consider a subspecialty consultation.     

A lyophilized reagent for standardization of the activated partial thromboplastin time]

Native partial thromboplastin, prepared from cadaver brain thromboplastin (a reagent), is a cephalin analog used to detect disorders in the first phase of coagulation. It was lyophilized with the aim of its stabilization, potential commercial manufacture, and introduction into practical clinical laboratories. Native emulsion was distributed into 0.2 ml penicillin flasks and lyophilized for 18-20 hrs in IZ-9 (CSR) or similar equipment at the maximum temperature of the product 5 degrees C. Lyophilized reagent is a white or slightly cream-colored powder. It retains its activity for at least a year as evidenced by the activated partial thromboplastin time test. The range of activities within one lot is less if commercial lyophilized donor reference plasma is used in the test. The reagent is stored in a refrigerator at 4-8 degrees C.     

One-step chromogenic equivalent of activated partial thromboplastin time evaluated for clinical application

We evaluated the clinical usefulness of a recently developed semi-automated one-step chromogenic equivalent of activated partial thromboplastin time (APTT; Behring). This simple test is easily adaptable for automation. Generally, the results with this chromogenic one-step APTT were at least as precise as those obtained with comparative coagulometric methods. The chromogenic one-step APTT showed, both in vitro and in vivo, adequate sensitivity to congenital intrinsic factor deficiency but no sensitivity to Factor VII deficiency. Unlike a two-step coagulometric APTT (Dade), the one-step chromogenic APTT seemed sensitive to activation products of the contact system, which are present in immunoadsorbed factor-deficient plasma. The in vitro sensitivity of the chromogenic APTT to heparin was comparable with that of a coagulometric APTT, but the sensitivity to heparin in patients' samples differed slightly. The chromogenic APTT is relatively insensitive to anomalies in the fibrinogen-fibrin conversion. Finally, we observed discrepancies between the chromogenic and coagulometric APTT results for plasma of patients with disseminated intravascular coagulation. We conclude that this one-step chromogenic APTT warrants further evaluation for possible use as a routine test for the clinical laboratory.     

Test for detection of activated partial thromboplastin time using ellagic acid]

A simple and sensitive method for estimation of activated partial thromboplastin time (APTT) is developed, making use a complex reagent containing the activator (plant phospholipids) and contact factor (ellagic acid). The test requires additionally only 0.025 M CaCl2. The test is more sensitive to the presence of heparin in the blood and to insufficiency of blood clotting factors VIII and IX than the reagents containing insoluble substances (kaolin and animal phosphatides). Addition of soluble ellagic acid into reagent for APTT estimation allows studies on optic coagulometers.