Blood haemoglobin estimation

HB estimation

1. BLOOD- HAEMOGLOBIN ESTIMATION BY: KANIKA

2. METHODS Visual methods Sahli’s acid hematin Tallqvist hemoglobin chart WHO hemoglobin Color scale Photoelectric methods Oxyhemoglobin Method Alkaline Hematin Method

3. Sahli’s Acid Haematin Method Principle Blood is mixed with an acid solution so that Hb is converted to brown coloured acid hematin . Diluted with water till brown colour matches that of brown glass standard. Hb value is read directly from the scale.

4. Equipments Sahli hemoglobinometer / Sahli haemometer Comparator box which has brown coloured two standard glass on either side. Central tube has two scales ( % scale and g/ dL scale) Sahli pipette(marked at 20 microlite or 0.02 ml- millilitre ) Stirrer Reagents- N/10 hydrochloric acid, Distilled water

5. Steps Add N/10 HCl into the central tube till the level of 2 grams. Clean the finger site with spirit swab. At least get a drop blood. Blood sample in the pipette upto 20 micro litre or 0.02 mark. Slowly add blood into the tube containing HCl . Rinse the pipette by drawing in and blowing out the mix 3-4 times. Mix with a stirrer. Allow to stand for 10 minutes.

6. Place the hemoglobino meter tube in the comparator and add distilled water to the solution drop by drop stirring with the glass rod till its colour matches with that of the comparator glass. Remove the glass rod from the solution and hold vertically in the tube while matching the colour. Keep adding distilled water until it matches the colour of the standard tube. Take the reading in gram scale. Record and show to the patient. Plan patient care accordingly.

7. Advantages Easy to perform Quick Inexpensive Can be used as a bedside procedure Does not require technical expertise

8. Disadvantages For maximum colour, longer time is required Perfect matching with brown glass standard is not possible Source of light will influence the comparison of colours

9. TALLQVIST HAEMOGLOBIN CHART Use only approved test- strips. Blood obtained from finger puncture. Add a drop of blood to one end of a test-strip / absorbent paper, just enough to completely cover an aperture in the colour scale. Wait about 30 sec, then read immediately by comparing the blood stain with the colour scale to find the best colour match.

10. Keep the test- strip close to the back of the colour scale. Avoid direct sunlight. Avoid marked shade. Avoid your own shadow or any other shadow If the blood stain matches one of the shades of red exactly, record the Hb value. If the colour lies between two shades , record the middle value. If in doubt between two shades, record the lower value. Discard the test –strip after use. Cheap and simple Error-20 to 50 percent