Bleeding time

A crude test of hemostasis.

An indication of how well platelets interact with blood vessel walls to form blood clots.

Most often to detect qualitative defects of platelets.

Helps identify people who have defects in their platelet function.

Sometimes performed as a preoperative test to determine a patient’s risk of bleeding during and after surgery.

In the absence of a history of bleeding problems the test is not usually necessary.

Some medications adversely affect the results of the test and include:anticoagulants, diuretics, anticancer drugs, sulfonamides, thiazide, aspirin and aspirin-containing preparations, and nonsteroidal anti-inflammatory drugs.

Aspirin should not be taken two weeks prior to the test.

Test is very insensitive to aspirin and may miss as many as one third of cases of vWD

Four methods to perform the bleeding test.

The Ivy method is the traditional format with a blood pressure cuff placed on the upper arm and inflated to 40 mM Hg.

An automatic, spring-loaded blade device is most commonly used to make a standard-sized cut and the time from when the stab wound is made until all bleeding has stopped is measured and is called the bleeding time.

Every 30 seconds, filter paper is used to draw off the blood and the test is finished when bleeding has stopped completely.

The template, and modified template, are variations of the Ivy method.

The Duke method utilizes a nick is made in an ear lobe or a fingertip.

Prolonged bleeding time occurs when the normal function of platelets is impaired, or there are a lower than normal number of platelets in the blood.

An elevated bleeding time is present with severe thrombocytopenia, platelet dysfunction, vascular defects, Von Willebrand’s disease, or other abnormalities.

Normal bleeding time is from 2 to 6 minutes.

Bleeding time is increased in disorders of platelet count, uremia, and ingestion of aspirin and other antiinflammatory medications.


Prolonged when BUN greater than 60mg/dL or serum creatinine level greater than 6.7 mg/dL.

The hematocrit level is inversely correlated with the bleeding time.

Prolonged bleeding time from aspirin 8-10 days.

Desmopressin can reverse the effect of aspirin on bleeding time.

A bleeding time twice the upper normal limit may be an indication for a platelet transfusion in a bleeding patient.

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