Bleeding time

Last updated: Wednesday, 31, March, 2004

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Item Process
Specimen

In vivo test.

This test is largely obsolete and rarely indicated. It has been replaced in most circumstances by more reproducible and less invasive tests such as PFA100 closure times.

Due consideration should be given before requesting a bleeding time: it is rarely indicated in a child; in the elderly skin atrophy is an important cause of a prolonged bleeding time.

The bleeding time should never be performed before the result of a platelet count is known and should not be performed if the platelet count is reduced. Aspirin and NSAID use in the previous week should be excluded prior to performing the test.

Method

The bleeding time is subject to many technical and physiological variables. The modified Ivy technique must be performed by experienced laboratory staff.

A sphygmomanometer cuff is inflated to 40 mmHg; a paediatric cuff must be used when testing children. Standardised superficial incisions are made in the skin of the volar aspect of the forearm, usually with a commercial, disposable device. The time when bleeding ceases is reported. The Duke (lancet stab to ear lobe) and Ivy (lancet stabs to forearm) techniques are obsolete.

Reference Interval

Modified Ivy: <9 minutes.

Consult pathologist.

Application

The bleeding time should not be used as a 'screening test' for inherited or acquired bleeding disorders as it has very low sensitivity and specificity.

Although it may be abnormal in von Willebrand’s disease, inherited disorders of platelet function, uraemia, myeloproliferative disorders and after aspirin and NSAID use, its ability to predict surgical bleeding and/or the need for therapeutic cover in these situations is very limited.

Bleeding time can also be prolonged after ingestion of some foods, eg, garlic.

Interpretation

Variably prolonged in moderate to severe von Willebrand's disease, inherited and acquired disorders of platelet function.

May be prolonged in some collagen disorders (eg, Ehlers Danlos syndrome). Artefactual prolongation is common, particularly due to technical variables.

A normal result does not exclude a clinically significant abnormality.

Interpretation is particularly difficult in children.

Reference

Coller BS. In: Colman RW et al, eds. Hemostasis and Thrombosis. Lippincott 1987.

Lind SE. Blood 1991; 77: 2547-2552.

Harrison P et al. Clin Lab Haem 2002; 24: 225-232.