Bleeding Time (BT) Test

1. Objective:

The objective of the Bleeding Time (BT) test was to evaluate the time taken for small blood vessels to stop bleeding after a standardized skin puncture, thus assessing platelet function and vascular integrity.

2. Principle:

The test was based on the principle that bleeding time reflects platelet plug formation at the site of vascular injury. Any defect in platelet number, function, or vessel wall integrity prolonged the bleeding time.

3. Materials:

Sterile lancet or bleeding time device

Stopwatch

Filter paper (Whatman No. 1)

Sphygmomanometer

Alcohol swab

Ruler

Cotton and adhesive bandage

4. Procedure (Duke’s Method or Ivy’s Method):

(Ivy’s Method – more standard):

1. The patient’s forearm was cleaned and a blood pressure cuff was inflated to 40 mmHg.

2. A standardized incision (usually 5 mm long, 1 mm deep) was made on the volar surface using a lancet.

3. The stopwatch was started immediately.

4. Every 30 seconds, the blood was gently blotted with filter paper without touching the wound.

5. The time until bleeding stopped completely was recorded as the Bleeding Time.

6. The wound was cleaned and dressed after the test.

5. Result:

Normal range: 2 – 7 minutes

Prolonged BT:

Thrombocytopenia

Platelet function disorders (e.g., Glanzmann’s, Bernard-Soulier)

von Willebrand disease

Use of aspirin or NSAIDs

6. Uses:

Assessed primary hemostasis (platelet plug formation)

Diagnosed platelet function disorders

Evaluated bleeding tendency before surgery (less common now)

Monitored the effects of anti-platelet drugs

7. Consultation:

A physician interpreted BT results along with platelet count, PT, and aPTT. Abnormal results indicated the need for further platelet function studies or referral to a hematologist.

© Mr Adedeji Adeyanju via WhatsApp