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Clinical use of coagulation tests

INTRODUCTION

Routine tests of blood coagulation, such as the prothrombin time (PT), activated partial thromboplastin time (aPTT), and thrombin time (TT), are frequently ordered to assess clotting function in patients. Additional tests, such as anti-factor Xa activity, are sometimes used.

The nature of these tests and the evaluation of abnormal test results will be reviewed here. Additional topic reviews discuss the following:

Overviews of the coagulation pathway and hemostasis (see "Overview of hemostasis" and "Vitamin K and the synthesis and function of gamma carboxyglutamic acid")

Approach to patients with abnormal bleeding (see "Approach to the adult patient with a bleeding diathesis" and "Approach to the child with bleeding symptoms" and "Rare (recessively inherited) coagulation disorders" and "Coagulation abnormalities in patients with liver disease")

Assessment of hemostasis preoperatively (see "Preoperative assessment of hemostasis")

                                 

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Literature review current through: Oct 2014. | This topic last updated: May 1, 2014.
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References
Top
  1. Spaet TH. Case 20-1979: false prolongation of prothrombin time in polycythemia. N Engl J Med 1979; 301:503.
  2. Adcock DM, Kressin DC, Marlar RA. Minimum specimen volume requirements for routine coagulation testing: dependence on citrate concentration. Am J Clin Pathol 1998; 109:595.
  3. Chuang J, Sadler MA, Witt DM. Impact of evacuated collection tube fill volume and mixing on routine coagulation testing using 2.5-ml (pediatric) tubes. Chest 2004; 126:1262.
  4. McLaren G, Hanna C, Mills L, et al. Comparison of sampling methods for obtaining accurate coagulation values in hemodialysis patients with heparinized central venous catheters. Nephrol Nurs J 2001; 28:632.
  5. Besley M, Thomas A, Salter S, et al. Control of oral anticoagulation in patients using long-term internal jugular catheters for haemodialysis access. Int J Artif Organs 1992; 15:277.
  6. van Genderen PJ, Gomes M, Stibbe J. The reliability of Hickman catheter blood for the assessment of activation markers of coagulation and fibrinolysis in patients with hematological malignancies. Thromb Res 1994; 73:247.
  7. Delate T, Witt DM, Jones JR, et al. Falsely elevated international normalized ratio values in patients undergoing anticoagulation therapy: a descriptive evaluation. Chest 2007; 131:816.
  8. Zürcher M, Sulzer I, Barizzi G, et al. Stability of coagulation assays performed in plasma from citrated whole blood transported at ambient temperature. Thromb Haemost 2008; 99:416.
  9. Gottfried EL, Adachi MM. Prothrombin time and activated partial thromboplastin time can be performed on the first tube. Am J Clin Pathol 1997; 107:681.
  10. Brigden ML, Graydon C, McLeod B, Lesperance M. Prothrombin time determination. The lack of need for a discard tube and 24-hour stability. Am J Clin Pathol 1997; 108:422.
  11. Hirsh J, Poller L. The international normalized ratio. A guide to understanding and correcting its problems. Arch Intern Med 1994; 154:282.
  12. Frith D, Goslings JC, Gaarder C, et al. Definition and drivers of acute traumatic coagulopathy: clinical and experimental investigations. J Thromb Haemost 2010; 8:1919.
  13. Perry DJ. Factor VII Deficiency. Br J Haematol 2002; 118:689.
  14. Ansell J, Hirsh J, Hylek E, et al. Pharmacology and management of the vitamin K antagonists: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest 2008; 133:160S.
  15. Becker DM, Humphries JE, Walker FB 4th, et al. Standardizing the prothrombin time. Calibrating coagulation instruments as well as thromboplastin. Arch Pathol Lab Med 1993; 117:602.
  16. van den Besselaar AM, Poller L, Tripodi A. Guidelines for thromboplastins and plasmas used to control oral anticoagulant therapy. WHO Technical Report Series 1999; 889:64.
  17. Tripodi A, Primignani M, Lemma L, et al. Detection of the imbalance of procoagulant versus anticoagulant factors in cirrhosis by a simple laboratory method. Hepatology 2010; 52:249.
  18. Moll S, Ortel TL. Monitoring warfarin therapy in patients with lupus anticoagulants. Ann Intern Med 1997; 127:177.
  19. Robert A, Le Querrec A, Delahousse B, et al. Control of oral anticoagulation in patients with the antiphospholipid syndrome--influence of the lupus anticoagulant on International Normalized Ratio. Groupe Méthodologie en Hémostase du Groupe d'Etudes sur l'Hémostases et la Thrombose. Thromb Haemost 1998; 80:99.
  20. Schmaier AH. Contact activation: a revision. Thromb Haemost 1997; 78:101.
  21. Price EA, Jin J, Nguyen HM, et al. Discordant aPTT and anti-Xa values and outcomes in hospitalized patients treated with intravenous unfractionated heparin. Ann Pharmacother 2013; 47:151.
  22. Hull RD, Raskob GE, Brant RF, et al. Relation between the time to achieve the lower limit of the APTT therapeutic range and recurrent venous thromboembolism during heparin treatment for deep vein thrombosis. Arch Intern Med 1997; 157:2562.
  23. D'Angelo A, Seveso MP, D'Angelo SV, et al. Effect of clot-detection methods and reagents on activated partial thromboplastin time (APTT). Implications in heparin monitoring by APTT. Am J Clin Pathol 1990; 94:297.
  24. JIM RT. A study of the plasma thrombin time. J Lab Clin Med 1957; 50:45.
  25. Mammen EF. Seminars in Thrombosis and Hemostasis. Semin Thromb Hemost 1983; 9:1.
  26. Zehnder JL, Leung LL. Development of antibodies to thrombin and factor V with recurrent bleeding in a patient exposed to topical bovine thrombin. Blood 1990; 76:2011.
  27. Rapaport SI, Zivelin A, Minow RA, et al. Clinical significance of antibodies to bovine and human thrombin and factor V after surgical use of bovine thrombin. Am J Clin Pathol 1992; 97:84.
  28. Niewiarowski S, Kirby EP, Stocker K. Throbocytin-a novel platelet activating enzyme from Bothrops atrox venom. Thromb Res 1977; 10:863.
  29. Teien AN, Lie M. Evaluation of an amidolytic heparin assay method: increased sensitivity by adding purified antithrombin III. Thromb Res 1977; 10:399.
  30. Hirsh J, Warkentin TE, Raschke R, et al. Heparin and low-molecular-weight heparin: mechanisms of action, pharmacokinetics, dosing considerations, monitoring, efficacy, and safety. Chest 1998; 114:489S.
  31. Welsby IJ, McDonnell E, El-Moalem H, et al. Activated clotting time systems vary in precision and bias and are not interchangeable when following heparin management protocols during cardiopulmonary bypass. J Clin Monit Comput 2002; 17:287.
  32. Furuhashi M, Ura N, Hasegawa K, et al. Sonoclot coagulation analysis: new bedside monitoring for determination of the appropriate heparin dose during haemodialysis. Nephrol Dial Transplant 2002; 17:1457.
  33. Linkins LA, Julian JA, Rischke J, et al. In vitro comparison of the effect of heparin, enoxaparin and fondaparinux on tests of coagulation. Thromb Res 2002; 107:241.
  34. Marmur JD, Anand SX, Bagga RS, et al. The activated clotting time can be used to monitor the low molecular weight heparin dalteparin after intravenous administration. J Am Coll Cardiol 2003; 41:394.
  35. Nowak G. The ecarin clotting time, a universal method to quantify direct thrombin inhibitors. Pathophysiol Haemost Thromb 2003; 33:173.
  36. Gosselin RC, King JH, Janatpour KA, et al. Comparing direct thrombin inhibitors using aPTT, ecarin clotting times, and thrombin inhibitor management testing. Ann Pharmacother 2004; 38:1383.
  37. Fenyvesi T, Jörg I, Harenberg J. Monitoring of anticoagulant effects of direct thrombin inhibitors. Semin Thromb Hemost 2002; 28:361.
  38. Salmela B, Joutsi-Korhonen L, Saarela E, Lassila R. Comparison of monitoring methods for lepirudin: impact of warfarin and lupus anticoagulant. Thromb Res 2010; 125:538.
  39. van Ryn J, Stangier J, Haertter S, et al. Dabigatran etexilate--a novel, reversible, oral direct thrombin inhibitor: interpretation of coagulation assays and reversal of anticoagulant activity. Thromb Haemost 2010; 103:1116.
  40. Avecilla ST, Ferrell C, Chandler WL, Reyes M. Plasma-diluted thrombin time to measure dabigatran concentrations during dabigatran etexilate therapy. Am J Clin Pathol 2012; 137:572.
  41. el-Sayed MS. Effects of exercise on blood coagulation, fibrinolysis and platelet aggregation. Sports Med 1996; 22:282.
  42. Ogasawara M, Aoki K, Katano K, et al. Activated partial thromboplastin time is a predictive parameter for further miscarriages in cases of recurrent fetal loss. Fertil Steril 1998; 70:1081.
  43. Landi G, D'Angelo A, Boccardi E, et al. Venous thromboembolism in acute stroke. Prognostic importance of hypercoagulability. Arch Neurol 1992; 49:279.
  44. Reddy NM, Hall SW, MacKintosh FR. Partial thromboplastin time: prediction of adverse events and poor prognosis by low abnormal values. Arch Intern Med 1999; 159:2706.
  45. Tripodi A, Chantarangkul V, Martinelli I, et al. A shortened activated partial thromboplastin time is associated with the risk of venous thromboembolism. Blood 2004; 104:3631.
  46. Aboud MR, Ma DD. Increased incidence of venous thrombosis in patients with shortened activated partial thromboplastin times and low ratios for activated protein C resistance. Clin Lab Haematol 2001; 23:411.
  47. Hron G, Eichinger S, Weltermann A, et al. Prediction of recurrent venous thromboembolism by the activated partial thromboplastin time. J Thromb Haemost 2006; 4:752.
  48. Zakai NA, Ohira T, White R, et al. Activated partial thromboplastin time and risk of future venous thromboembolism. Am J Med 2008; 121:231.
  49. Baccarelli A, Martinelli I, Zanobetti A, et al. Exposure to particulate air pollution and risk of deep vein thrombosis. Arch Intern Med 2008; 168:920.
  50. Lossing TS, Kasper CK, Feinstein DI. Detection of factor VIII inhibitors with the partial thromboplastin time. Blood 1977; 49:793.
  51. Galli M, Finazzi G, Norbis F, et al. The risk of thrombosis in patients with lupus anticoagulants is predicted by their specific coagulation profile. Thromb Haemost 1999; 81:695.
  52. Arnout J, Meijer P, Vermylen J. Lupus anticoagulant testing in Europe: an analysis of results from the first European Concerted Action on Thrombophilia (ECAT) survey using plasmas spiked with monoclonal antibodies against human beta2-glycoprotein I. Thromb Haemost 1999; 81:929.
  53. Brandt JT, Barna LK, Triplett DA. Laboratory identification of lupus anticoagulants: results of the Second International Workshop for Identification of Lupus Anticoagulants. On behalf of the Subcommittee on Lupus Anticoagulants/Antiphospholipid Antibodies of the ISTH. Thromb Haemost 1995; 74:1597.
  54. Walenga JM, Fasanella AR, Iqbal O, et al. Coagulation laboratory testing in patients treated with argatroban. Semin Thromb Hemost 1999; 25 Suppl 1:61.
  55. Perry DJ, Fitzmaurice DA, Kitchen S, et al. Point-of-care testing in haemostasis. Br J Haematol 2010; 150:501.