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.
6. 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.
7. 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.
8. Advantages
Easy to perform
Quick
Inexpensive
Can be used as a bedside procedure
Does not require technical expertise
9. 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
10. 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.
11. 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