•Duke's Method (Earlobe / Fingertip)
Determination of Bleeding Time
Difficulty: Beginner• Est. Duration: 10–15 min• Protocol Steps: 6 Steps
Required Reagents & Equipment
- Sterile single-use lancet (3mm depth)
- Whatman No. 1 circular filter paper
- 70% Isopropyl alcohol swabs
- Precision digital/analog stopwatch
- Sterile surgical gloves & sharps container
- Adhesive bandage strip
Biosafety & Precautionary Directives
- •Always use a sterile, single-use lancet — never reuse lancets across subjects.
- •Wear protective nitrile or surgical gloves throughout the clinical procedure.
- •Dispose of used lancets immediately into a biohazard sharps container.
- •Never wipe or squeeze the puncture site — touching gently avoids tissue fluid dilution.
Step 1 of 6Pacing: 4s
Site Preparation & Disinfection
Thoroughly clean the earlobe or fingertip puncture site using a 70% spirit swab. Allow the alcohol to air-dry completely so residual spirit does not hemolyze blood cells or alter timing.
Laboratory Tip:Air-drying takes ~15 seconds. Never blow air on the site to accelerate drying.