Sahil's Method an Accurate Way to Check Hemoglobin in Community- Step by Step Guide

Hemoglobin Check Using Sahli’s Method

The Sahli's method, also known as the acid hematin method, is a manual technique to estimate hemoglobin concentration in the blood. Here is a step-by-step guide to performing a hemoglobin check using Sahli's method:

Fig. 1 Sahil's Heamoglobinometer

Materials Needed:

1. Sahli's hemoglobinometer (also called a hemoglobinometer or hemometer)

2. Sahli's pipette (0.02 ml capacity)

3. Sahli’s graduated hemoglobin tube

4. N/10 hydrochloric acid (HCl)

5. Distilled water

6. Mixing rod (usually a glass rod)

7. Blood sample (finger prick or venous blood)

8. Lancet and alcohol swabs (if using a finger prick)

9. Cotton balls or gauze

Procedure:

1. Preparation:

   - Ensure all equipment is clean and dry.

   - Place the Sahli’s hemoglobinometer on a flat, stable surface.

2. Filling the Tube:

   - Add N/10 hydrochloric acid (HCl) to the graduated hemoglobin tube up to the 2 g/dl mark. This creates a starting point for the acid hematin reaction.

3. Collecting the Blood Sample:

   - If using a finger prick, clean the fingertip with an alcohol swab and let it dry.

   - Use a sterile lancet to prick the fingertip and wipe away the first drop of blood with a cotton ball.

   - Collect the blood sample using the Sahli’s pipette (0.02 ml). Ensure that the pipette is filled exactly to the mark without air bubbles.

4. Adding Blood to the Acid:

   - Carefully add the blood sample from the pipette into the graduated hemoglobin tube containing the hydrochloric acid. Be precise to avoid any loss of blood.

5. Mixing:

   - Mix the blood and acid thoroughly using the mixing rod. Stir the mixture gently to ensure complete reaction, converting hemoglobin to acid hematin.

   - Allow the mixture to stand for a few minutes to ensure complete reaction and color development.

6. Matching the Color:

   - After the reaction, add distilled water drop by drop to the graduated tube while continuously mixing. 

   - Continue adding water until the color of the solution matches the standard color comparison tubes provided with the Sahli’s hemoglobinometer. These tubes represent different hemoglobin concentrations (usually in grams per deciliter, g/dl).

7. Reading the Result:

   - Once the color of the solution matches the standard, read the hemoglobin concentration directly from the graduated tube at the meniscus level (where the bottom of the liquid curve touches the scale).

   - Record the hemoglobin concentration in g/dl.

Precautions:

1. Accuracy:

   - Ensure accurate measurement of blood and hydrochloric acid.

   - Avoid air bubbles in the pipette and ensure thorough mixing for accurate results.

2. Hygiene:

   - Use sterile equipment and maintain hygiene to avoid contamination and infection.

   - Dispose of lancets and used materials properly.

3. Color Matching:

   - Proper lighting is important for accurate color matching.

   - Be consistent with the angle of viewing the color comparison to avoid parallax errors.

Interpretation:

- Normal Hemoglobin Levels:

  - Adult men: 13.8 to 17.2 g/dl

  - Adult women: 12.1 to 15.1 g/dl

  - Children: 11 to 16 g/dl (varies with age)

Abnormal hemoglobin levels could indicate conditions like anemia (low hemoglobin) or polycythemia (high hemoglobin).

By following these steps carefully, you can accurately determine hemoglobin levels using Sahli’s method. This method is widely used in resource-limited settings due to its simplicity and low cost.