两种部分凝血活酶试剂测定结果的比较

目的评价部分凝血活酶试剂对方法学的影响。方法利用乏因子血浆、体外配制的肝素化血浆和临床病人标本，对ＩＬ－ＴｅｓｔＴＭ和Ｐａｃｉｆｉｃ Ｈｅｍｏｓｔａｓｉｓ　两种不同部分凝血活酶试剂进行平行测定。结果两种试剂对因子敏感性无显著性差异（因子Ⅶ，因子ⅨＰ值，分别大于０．９，０．７），但对肝素的敏感性差异显著（Ｐ＜０．００１）。而利用病人血浆标本表明使用ＡＰＴＴ比值报告结果并未改善两种试剂测定结果的可比性，并发现随着ＡＰＴＴ结果的延长，其精确性下降。结论针对不同部分凝血活酶试剂要建立各自的肝素治疗范围。     

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…     

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…     

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.     

活化的部分凝血活酶时间异常结果的判定标准

目的　探讨仪器法测定活化的部分凝血活酶时间 (APTT)的参考范围和异常结果的判定标准。方法　用两种APTT试剂测定正常人、口服抗凝药病人、标准Ⅷ因子血浆及肝素钙血浆的APTT值。分析两种APTT试剂测定的结果间是否存在差异。结果　两种APTT试剂测定结果若以秒的形式报告有显著差异 ,若以APTT比值的形式报告则无显著差异。结论　各临床实验室应确定自己的参考值范围。检测结果以比值的形式报告 ,各实验室间的结果具有可比性。仪器法测定APTT应以病人结果比正常对照延长 7s以上为异常的判定标准。     

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：251L01)、APTT-EA试剂盒(批号：420K03)、正常质控物(NCCP,批号：100L02)、异常质控物(ACCP,批号：106K01)。     

从桡动脉及中心静脉置管采血检测活化部分凝血活酶时间的可行性研究

目的研究从肝素维持的桡动脉及输液中的中心静脉置管采血检测活化部分凝血活酶时间(APTT)的可行性。方法对30例同时带有桡动脉测压及中心静脉置管的病人,分别在同一时段从桡动脉置管、输液中的中心静脉置管及外周静脉穿刺采血检测APTT,以外周静脉穿刺采血测得的APTT值为准,把从桡动脉置管、输液中的中心静脉置管采血测得的APTT值分别与之比较;对另30例仅带有中心静脉置管的病人,分别在同一时段从输液中的中心静脉置管及外周静脉穿刺采血检测APTT,比较两组检测结果。结果从肝素维持的桡动脉置管中采血(采血前先弃去5ml血)、从输液中的中心静脉置管中采血(采血前停输液,弃去10ml血)与外周穿刺采血所测得的APTT值比较,差异无统计学意义(P>0.05);从输液中的中心静脉置管中采血(采血前停输液并弃去5ml血)与外周静脉穿刺采血所测得的APTT值比较,差异亦无统计学意义(P>0.05)。结论从以肝素维持的桡动脉置管及输液中的中心静脉置管采血代替外周静脉穿刺采血检测APTT是可行的,只要在留取标本前弃去一定量的血(桡动脉弃血5ml,输液中的中心静脉弃血5ml)。     

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。     

标本血量不足对凝血酶原时间及活化部分凝血活酶时间检测结果的影响

目的：分析标本血量不足对患者凝血酶原时间（PT）、活化部分凝血活酶时间（APTT）检测结果的影响。方法选择58例血量不足标本,要求血细胞比容在20％～55％,离心后无溶血、脂血及黄疸。按血量与抗凝剂比例分为8∶1组与7∶1组两组,再分别抽取两组患者合格血量（2．7 mL ）标本作为各自对照组,检测4个组血样的PT、APTT。结果 PT在血量与抗凝剂比例为8∶1组和8∶1对照组相比差异无统计学意义（P＞0．05）,在血量与抗凝剂比例为7∶1组与7∶1对照组相比差异有统计学意义（P＜0．05）;APTT在血量与抗凝剂比例为8∶1、7∶1组与相应的对照组相比差异有统计学意义（P＜0．05）。结论凝血项目的检测中,PT、APTT 的结果受血液和抗凝剂比例的影响。     

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。     

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。     

Prognostic value of the activated partial thromboplastin time after orthotopic liver transplantation

Summary In this prospective study, we evaluated the predictive value of activated partial thromboplastin time on day 8 post transplantation for event-free survival in patients who had had orthotopic liver transplants; both death and retransplantation within 6 months were the events considered. In a 4-year period, 109 patients had orthotopic liver transplants in our hospital, and 104 were eligible for the study since they survived and were not given new transplants within 8 days. The activated partial thromboplastin time was significantly longer in patients who survived event-free for less than 6 months than in those with longer event-free survivals. Kaplan-Meier curves showed that patients with normal activated partial thromboplastin times were nine times more likely to survive more than 6 months without events than patients with prolonged values. The positive predictive value of activated partial thromboplastin time for event-free survival was 88% and the negative predictive value was 54%, indicating that the test is useful for predicting patient outcome. We suggest that activated partial thromboplastin time be performed on day 8 post transplantation to predict the medium-term event-free survival.     

Chromogenic substrates for activated partial thromboplastin time testing: Are they worth using?

Summary In hemostasis testing the development of chromogenic substrates provides an alternative to the traditional methods based on the detection of forming clots. The new technology has often replaced the clotting tests, especially in the area of single clotting factor and inhibitor assay, less frequently for global screening tests. We report studies of the validity and clinical application of two reagents for activated partial thromboplastin time (APTT) testing with chromogenic substrates in comparison with the conventional clotting method. Congenital deficiencies of the intrinsic coagulation pathway, other than hypo- and dysfibrinogenemia detected by chromogenic APTT, agreed with those detected by the clotting APTT. The results with the two methods for plasma under heparin treatment suggest a lesser responsiveness of the chromogenic methods to heparinization. The chromogenic methods demonstrated the presence of the lupus anticoagulant in the majority of tested samples of known lupus subjects, but with a lower responsiveness than the clotting method. In conclusion, we found chromogenic APTT suitable for hemostasis testing because it generally gives the same information as the conventional clotting method with the exception of heparin monitoring and lupus anticoagulant detection, where an improved sensitivity would be desirable. Presented at the ‘2nd International Symposium on Standardization and Quality Control of Coagulation Tests: Implications for the Clinical Laboratory’, Rome, September 28–29, 1989.     

实验前相关因素对测定新生儿血浆PT、APTT的影响

目的探讨抗凝、离心、黄疸等实验前相关因素对测定新生儿血浆凝血酶原时间（PT）、活化部分凝血活酶时间（API]r）的影响,从而进一步优化试验条件。方法本试验选取100名外科术前体检无异常发现的新生儿,所有入选新生儿均无血栓性疾病及出凝血功能障碍,无心、肾、肝等重要脏器疾病。将此100名新生儿分为3组,分别为抗凝剂比例影响组（包括抗凝剂比例9：1组和抗凝剂比例校正组）、离心条件影响组[2000r／min（离心半径为10cm）离心10min;3000r／min（离心半径为10em）离心10min组;2500r／min（离心半径为10cm）离心15min组]、生理性黄疸影响组。利用STAGO全自动血凝分析仪对以上几个处理组的标本进行检测,并且使用SPSS13．0统计软件对得到的数据进行比较,从而逐步优化实验条件。结果在相同离心条件下,抗凝剂9：1组的PT、APlTr明显延长。在抗凝剂比例经过校正的情况下,2000r／min（离心半径为10em）离心10min组的PT、APTT明显延长;3000r／min（离心半径为10cm）离心10min组中大部分标本PT、APTT正常,个别出现溶血的标本PT明显延长。2500r／min（离心半径为10cm）离心15min是新生儿检测胛、APTT的最适离心条件。在抗凝剂比例经过校正,2500r／min（离心半径为10cm）离心15min的条件下,生理性黄疸组与无生理性黄疸组的胛、APTT比较差异无统计学意义。结论在处理新生儿血浆标本时,应进行抗凝剂比例校正,离心转速不宜过快,否则容易引起溶血,从而引起实验误差。可以通过适当降低离心速度,延长离心时间来避免这种情况的发生。生理性黄疸基本不影响PT、APTT的测定。     

Comparison of two blood sampling methods in anticoagulation therapy: venipuncture and peripheral venous catheter

Aim. To compare prothrombin time and activated partial thromboplastin time values in concurrent blood samples obtained by direct venipuncture and from a peripheral venous catheter. Method. Concurrent blood samples obtained from catheters and by direct venipuncture were studied. Venipuncture samples were labelled as the reference (control) group and the peripheral venous catheter samples as the experimental group. A 21‐gauge needle was used in the venipuncture method and 18G, 20G, 22G catheters were used in the peripheral venous catheters method. In each case, after the blood samples were drawn by venipuncture and peripheral venous catheter the needles were drawn out, 1·8 ml of blood was added to 0·2 ml of citrate to give a 2 ml sample. The tube was shaken gently to mix the blood and citrate well. Results. No clinically significant difference between prothrombin time and activated partial thromboplastin time values were seen in the blood samples drawn by venipuncture and peripheral venous catheter methods. Discussion. It is recommended that peripheral venous catheter can be used for patients with high bleeding risk if they have a long hospital stay and frequent blood samples are needed. Relevance to clinical practice. In clinical applications, nurses may prefer the use of peripheral venous catheter to venipuncture both for the comfort of the patients who get anticoagulation therapy and for the prevention of the risks as a result of venipuncture. Application of peripheral venous catheter eliminates the risks of superficial bleeding, irritation, pain and anxiety caused by venipuncture.     

实验前相关因素对测定新生儿血浆PT、APTT的影响

目的探讨抗凝、离心、黄疸等实验前相关因素对测定新生儿血浆凝血酶原时间(PT)、活化部分凝血活酶时间(APTT)的影响,从而进一步优化试验条件。方法本试验选取100名外科术前体检无异常发现的新生儿,所有入选新生儿均无血栓性疾病及出凝血功能障碍,无心、肾、肝等重要脏器疾病。将此100名新生儿分为3组,分别为抗凝剂比例影响组(包括抗凝剂比例9∶1组和抗凝剂比例校正组)、离心条件影响组[2 000 r/min(离心半径为10 cm)离心10 min;3 000 r/min(离心半径为10 cm)离心10 min组;2 500 r/min(离心半径为10 cm)离心15 min组]、生理性黄疸影响组。利用STAGO全自动血凝分析仪对以上几个处理组的标本进行检测,并且使用SPSS 13.0统计软件对得到的数据进行比较,从而逐步优化实验条件。结果在相同离心条件下,抗凝剂9∶1组的PT、APTT明显延长。在抗凝剂比例经过校正的情况下,2 000 r/min(离心半径为10 cm)离心10 min组的PT、APTT明显延长;3 000 r/min(离心半径为10 cm)离心10 min组中大部分标本PT、APTT正常,个别出现...     

Use of the activated partial thromboplastin time for monitoring heparin therapy: Problems and possible solutions

Summary There is considerable variation in available methods for the activated partial thromboplastin time (APTT), giving widely differing results with patients on heparin treatment. The study is primarily concerned with the assessment of five of the widest used APTT reagents. The heparin response of these reagents has been related to their lipid composition and physical properties. Of the various correlations between lipid composition of the reagents and clotting performance only electrophoretic mobility was associated with the APTT response to heparin. There was a highly significant negative correlation between the APTT prolongation with heparin and electrophoretic mobility. When plasma is heparinizedin vitro a differing order of ranking for APTT reagents is obtained than when heparinized patients are tested. The APTT response in patients with recent thrombosis must therefore be the best guide to the clinical dose of heparin. The therapeutic range of conventional heparin therapy is generally regarded as 1.5–2.5 times the control. External quality assessment programmes in the UK and USA have shown considerable differences between heparin dosage according to the APTT test systems. The definition of the therapeutic range must be derived from randomized clinical studies. The need for progress in standardization of the APTT monitoring of heparin is demonstrated. Presented at the ‘2nd International Symposium on Standardization and Quality Control of Coagulation Tests: Implications for the Clinical Laboratory’, Rome, September 28–29, 1989.     

Use of the activated partial thromboplastin time for the diagnosis of congenital coagulation disorders: Problems and possible solutions

Summary The activated partial thromboplastin time (APTT) is a commonly performed laboratory procedure which is used for multiple purposes including monitoring of heparin therapy, detection of coagulation factor deficiency, and detection of lupus anticoagulants. Among the hereditary coagulation deficiencies, factor VIII and factor IX are the most common. APTT reagents differ widely in both their sensitivity to factor VIII and factor IX deficiencies as well as their responsiveness. Sensitivity may be defined as the ability to identify a deficiency state while responsiveness is indicated by the degree of prolongation of the APTT result as compared to the upper limit of normal. Reagents may be both sensitive and responsive or alternatively sensitive and relatively nonresponsive. Consequently, it is extremely important for each laboratory to carefully identify the upper limit of the normal range. A variety of preanalytical variables will also effect the sensitivity of the APTT to factor deficiency states. These variables include specimen handling and the preparation of platelet poor plasma. The instrument effect is also of importance. Selection of the reagent tends to have the most impact on senstivity and responsiveness while instrumentation affects the precision of a given APTT. The composition and concentration of phospholipid in APTT reagents does have an effect on reagent responsiveness and sensitivity. Sensitivity to factor deficiencies does not necessarily parallel sensitivity to lupus anticoagulants. Presented at the ‘2nd International Symposium on Standardization and Quality Control of Coagulation Tests: Implications for the Clinical Laboratory’, Rome, September 28–29, 1989.     

Standardization of the activated partial thromboplastin time for monitoring of heparin therapy: Where should we go?

Summary Standardization of the APTT for monitoring of heparin therapy is needed urgently. On the one hand, reference materials and methods should be established. On the other hand, the scale for reporting of results should be standardized. The implementation of a system based on a reference APTT method meets a number of practical problems. The use of lyophilized plasma as a reference material is of questionable value, until these products more satisfactorily resemble fresh patient plasma specimens. Presented at the ‘2nd International Symposium on Standardization and Quality Control of Coagulation Tests: Implications for the Clinical Laboratory’, Rome, September 28–29, 1989.