Aim: Determination of bleeding time
Reference: Haematology, Practical Human Anatomy and Physiology, S.R. Kale et al., Nirali Prakashan, Eight Edition, 2002, pp. 45-46
Definition
The bleeding time is required for a small cut to stop bleeding. When a blood vessel is injured, blood comes out for some time and stops because of the platelet plug formation. The duration of bleeding is the bleeding time. Normal value for bleeding time is 1- 3 minutes.
Significance
The bleeding time is mainly used to diagnose and treat hemorrhagic diseases. The bleeding time is also useful just before operations such as tonsillectomy. In such cases, it may point out an abnormal bleeding process. This will make the physician to take proper precautions. The bleeding time may be performed by the Duke, Ivy, and Macfarlane Method.
Duke method
The Duke Method is a historical technique used to measure bleeding time (BT), which assesses platelet function and vascular integrity. It was widely used before modern coagulation tests like platelet function assays and PFA-100 became standard.
Principle: The test measures the time taken for bleeding to stop after a small standardized incision is made on the earlobe or fingertip. The cessation of bleeding indicates the efficiency of platelet plug formation.
Materials Required: Sterile lancet or needle, Filter paper or blotting paper, Stopwatch, Alcohol swab, Cotton or gauze, Antiseptic solution
Procedure
1. Preparation: First, clean the earlobe (preferred) or fingertip using an alcohol swab to ensure proper hygiene and reduce the risk of infection. After cleaning, allow the area to dry completely before proceeding to the next step.
2. Incision: Using a sterile lancet, make a 2–3 mm deep puncture on the earlobe to initiate the procedure. Immediately after making the incision, start the stopwatch to accurately measure the required time.
3. Blood Absorption: Every 30 seconds, gently blot the blood with filter paper, ensuring that the wound is not touched directly. It is important to avoid applying pressure, as this may alter the results and affect the accuracy of the measurement.
4. Stopping Time: Continue blotting the blood at regular intervals until the bleeding stops completely. Once the bleeding has ceased, record the total time measured to ensure accurate results.
Normal Bleeding Time (Duke Method): 2–5 minutes (Varies based on factors like platelet count, capillary function, and external conditions.)
Ivy Method for Bleeding Time
The Ivy method is a widely used test for measuring bleeding time, which assesses platelet function, capillary integrity, and primary hemostasis. This method provides more standardized and reproducible results compared to the Duke method.
Principle: The Ivy method is based on the concept that:
When a standardized incision is made on the forearm, platelets aggregate to form a plug, followed by fibrin clot formation.
The time taken for the bleeding to stop represents primary hemostasis efficiency (platelet function and capillary response).
Unlike the Duke method (which uses the earlobe), the Ivy method is performed on the forearm under controlled conditions using a blood pressure cuff to standardize capillary pressure.
Materials Required: Sterile lancet or scalpel, Blood pressure cuff, Filter paper (Whatman No. 1), Stopwatch, Sterile alcohol swab, and cotton.
Procedure
1. Preparation: The patient should be seated in a relaxed position to ensure accurate results. Begin by cleaning the volar (inner) surface of the forearm with an alcohol swab to maintain hygiene and prevent infection. Next, inflate the blood pressure cuff to 40 mmHg to establish uniform capillary pressure throughout the procedure.
2. Incision: Using a sterile lancet or scalpel, make a small, standardized incision approximately 9 mm in length and 1 mm in depth on the prepared forearm. Immediately after making the incision, start the stopwatch to ensure precise time measurement.
3. Monitoring Bleeding: Using a sterile lancet or scalpel, create a standardized incision on the prepared forearm, measuring approximately 9 mm in length and 1 mm in depth. Immediately after making the incision, start the stopwatch to ensure accurate time measurement.
4. Recording Time: The total bleeding time is recorded from the moment of incision until bleeding stops.
3. Macfarlane Method for Bleeding Time
The Macfarlane method is one of the classical methods used to determine bleeding time, which assesses platelet function and primary hemostasis. This test is useful in diagnosing platelet disorders, vascular abnormalities, and conditions affecting blood clotting.
Principle: The Macfarlane method involves making a standardized incision on the earlobe and measuring the time taken for the bleeding to stop. The test evaluates vascular integrity and platelet plug formation.
Materials Required: Sterile lancet or disposable blade, Filter paper (Whatman No. 1), Stopwatch, Alcohol swab, Sterile cotton
Procedure
- Preparation: Begin by cleaning the earlobe with an alcohol swab to maintain hygiene and prevent infection. Allow the area to dry completely before proceeding. Ensure that the patient is in a relaxed position to facilitate an accurate and comfortable procedure.
- Incision: Using a sterile lancet, make a small, standardized puncture on the earlobe with a depth of approximately 3 mm. Immediately after making the incision, start the stopwatch to ensure precise time measurement.
- Monitoring Bleeding: Every 30 seconds, gently blot the blood with filter paper without touching the wound directly. Continue this process at 30-second intervals until the bleeding stops completely.
- Recording Time: The total bleeding time is recorded from the moment of incision until bleeding ceases.
Normal Bleeding Time: Macfarlane method reference range: 2 to 5 minutes
Sample Result Table for Bleeding Time by Different Methods
Patient ID | Method Used | Site of Incision | Standardization (BP Cuff Use) | Bleeding Time (Minutes) | Normal Range | Interpretation |
P001 | Duke Method | Earlobe | No | 3.5 min | 2-5 min | Normal |
P002 | Ivy Method | Forearm | Yes (40 mmHg) | 6.2 min | 2-7 min | Normal |
P003 | Macfarlane Method | Earlobe | No | 7.5 min | 2-5 min | Prolonged (Possible platelet dysfunction) |
P004 | Duke Method | Earlobe | No | 2.0 min | 2-5 min | Normal |
P005 | Ivy Method | Forearm | Yes (40 mmHg) | 8.0 min | 2-7 min | Prolonged (Investigate von Willebrand Disease) |
P006 | Macfarlane Method | Earlobe | No | 4.0 min | 2-5 min | Normal |
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