Coagulation profile

Keywords: Coagulation panel, Coagulation studies, Clotting profile, Clotting studies, Clotting panel, Coags, Coagulation studies

Specimen:

4.5 mL blood added to 0.5 mL citrate (+ 5 mL of EDTA anticoagulated blood if a full blood count is to be performed – consult with local laboratory).

Method:

This refers to a group of tests that includes the APTT (Activated partial thromboplastin time) and Prothrombin time and may include a Full blood count , Platelet count, Fibrinogen, Fibrin-degradation products, Thrombin time, D Dimer. Refer to laboratory.

Application:

Routinely a Full blood count is included to assess the adequacy of the platelet count.

The combination of an APTT and a PT as 'screening tests' may not detect all clinically significant bleeding disorders; the sensitivity of a detailed clinical assessment is high.

In the pre-operative assessment of patients, these tests should not be routinely performed. However, in a patient with a positive bleeding history or a clear clinical indication (e.g. liver disease), these tests are required.

Assessment of the risk of bleeding in a preoperative patient should include review of medications (including complementary medicines), a bleeding history assessment and physical examination. There are a number of bleeding assessment tools (BAT) available for this purpose.

Example of screening questions for bleeding history include questions concerning:

  1. Undue bleeding after cutting or biting the tongue.

  2. Significant easy bruising.

  3. Prolonged bleeding after dental extractions, or re-bleeding.

  4. Prolonged bleeding or excessive bruising after any surgery (major or minor).

  5. An adequate menstrual history, including family history of excessive or prolonged menses.

  6. Family history of post-op bleeding requiring transfusion.

  7. Current or recent medications including: aspirin, other analgesics, cold medications, warfarin.

  8. Excessive bleeding from umbilical cord stump.

If the bleeding history and examination is negative, then no coagulation studies may be necessary prior to minor procedures.

If the bleeding history is positive or if the surgery is likely to impair haemostasis e.g. cardiac surgery, then coagulation testing is recommended. This testing (including testing in addition to routine coagulation studies) will be guided by clinical history, medications, bleeding history, family history and the type of procedure. Haematologist advice recommended.

Interpretation:

See individual tests for interpretation of validated abnormal results.

Reference:

Eisenberg JM et al. Arch Surg 1982; 117: 48-51.

McPherson J and Street A. Aust Prescriber 1995; 18: 38-41.

Favoloro EJ. Aust J Med Sci 1994; 15: 39-45.

Chee YL et al. Guidelines on the assessment of bleeding risk prior to surgery or invasive procedures. BCSH, BJH 2008; 140: 496-504

Rodeghiero F et al. on behalf of the ISTH/SSC Joint VWF and Perinatal/Pediatric Hemostasis Subcommittees Working Group. ISTH/SSC bleeding assessment tool: a standardized questionnaire and a proposal for a new bleeding score for inherited bleeding disorders. J Thromb Haemost 2010; 8: 2063-2065.

Preoperative bleeding risk assessment resource. Available at www.blood.gov.au.