Bleeding time
(BT)

Sample type:

blood sample

Uses:

• Monitoring hemostatic therapy for patients diagnosed with bleeding associated with von Willebrand disease, a thrombocytopathy, or uremia (creatinine >1.1 mg/L impairs hemostasis)

• Prior to kidney biopsy in patients with uremia

Precautions:

No specific precautions

Interfering factor:

• Normal value for BT vary when the puncture site is not of uniform depth and width.

• Prolonged BT can reflect ingestion of 10 g of aspirin as long as 5 days before the test

• Other drugs may cause increased BT include dextran

Pre-analytical errors:

• collection of blood specimens

• prolonged tourniquet placing

• inappropriate mixing of a sample

corrective action

• good mixing for the sample

• proper collection of the sample

Post analytical errors:

• Check instrument settings

• Assure that all preventive maintenance has been done

Corrective action:

• Assure that the prescribed preventive maintenance for the instrument is performed

Reference range:

3-10 minute