What is Hemoglobin?
Practical
Requirements
How to prepare N/10 Hcl
Procedure
Observation & Result
Oxygen carrying capacity
Iron Content
Advantage & Disadvantage
Normal Levels
Questions
2. SLO
What is Hemoglobin?
Practical
Requirements
How to prepare N/10 Hcl
Procedure
Observation & Result
Oxygen carrying capacity
Iron Content
Advantage & Disadvantage
Normal Levels
Questions
3. What is Hemoglobin?
Hemoglobin (abbreviated Hb) is a red substance made of
iron and protein
Carries Oxygen to the cells
Carries Carbon dioxide away from the cells
4. Each molecule of hemoglobin contains four groups of
heme.
Heme is the iron component of hemoglobin.
Each group of heme can carry one molecule of oxygen.
5. A Hemoglobin molecule contains four
globin polypeptide chains composed of
amino acids.
Amino acids are a group of chemical
substances that form proteins.
Each hemoglobin molecule consists of
about 3.8% heme and 96.2% globin.
6. Practical
Aim
To determine the Hb content of blood (sahli’s method
its indirect method.)
Principle
The amount of Hb can be estimated by the
conversion of the known volume of blood into
acid-haematin by the addition of dilute N/10
Hcl and subsequent calorimetric comparison
with suitable standard.
10. How to prepare N/10 Hcl
Normality (N)
The normality of a solution is the number of gram equivalents in
1 litre of water.
A 1 N solution of Hcl contains 1 + 35 = 36 g of Hcl in water made
to 1 liter.
Diluting this solution 10 times will give N/10 Hcl.
12. Observation & Result
Compare your colour matching and record the
observations in your work book.
Take average of 3 readings as shown below, and
report your results,
1st
reading , when the colour is slightly darker than
the std……………..g/dl.
2nd
reading, when, after adding a few drops of distilled
water the colour exactly matches with std ………….g/dl.
3rd
reading, when, after adding some more drops, the
colour becomes a little lighter than the std……………
g/dl.
Hb=………………g/dl.
13. Oxygen carrying capacity
Knowing your Hb Conc. and that 1.0 g of Hb can
carry 1.34 ml 0f O2, calculate its O2 carrying
capacity as ……………..ml O2/dl.
Normal values :- Males – 21mL/dl ; Female –
18mL/dl
Iron Content
1g of Hb contains 3.35 mg iron, the amt of Hb can
be calculated.
14. Advantage
Sahli’s method (indirect method)is easy to perform and
convenient.
The cost is minimal.
It is not very time consuming (maximum fifteen minutes)
15. Disadvantage of Sahli’s method
The colour of the std may not always be reliable,
especially with old apparatus.
Sahli’s acid haematin method does not estimate
all the Hb. It estimate only oxyHb and reduced
Hb, but not the carboxyHb, methemoglobin and
sulfphhemoglobin.
Finally, the acid haematin is not true solution.
Some degree of precipitation may be present at
times, which may interfere with colour matching.
16. Normal Levels
12 to 16 (14 ± 2) grams per deciliter (g/dl)of blood in women
13.5 to 18 (16 ± 2) g/dl of blood in men
New born, 16 – 22 g/dl. It decreases to 9 – 14 g/dl by abt two months of
age. By 10yrs of age, the normal Hb Conc. Will be 12 - 14 g/dl.
There may be a slight decrease in Hb level after 50 yrs of age.
17. Other Methods
Visual method
Dare’s method
Haden’s method
Wintrobe’s method
Haldane’s method
Tallquist’s method
Gastrometric method
Spectrophotometric (these methods are rapid and give accurate result)
Oxyhemoglobin method
Cyanmethemoglobin method
Automated hemoglobinometry
Non-Automated hemoglobinometry
Alkaline- hematin method
Specific gravity method
Comparator method
19. Conditions that decrease Hb Conc.
I. Physiology
Pregnancy (due to hemodilution)
Children have lower values than adults
Women have lower values than men because the total
RBC count is less.
For male its due to testostreone stimulates
erythropoiesis in males.
I. Pathology
Different types of anemia
Relative decrease in Hb Conc. Occurs in different
pathological conditions that produce hemodilution,
for e.g excess ADH secretion as seen in pituitary
tumors.
20. Conditions that increase Hb Conc.
I. Physiology
High altitude (due to hypoxia)
New borns and infants
Excessive sweating (due to hemoconcentration)
I. Pathology
Conditions that produce hemoconcentration (due to
loss of body fluid) for example, severe diarrhea,
vomiting.
Conditions that produce hypoxia (e.g. congenital
heart disease, emphysema.
Polycythemia vera.
21. Questions
1. What is N/10 Hcl and how will you prepare it?
2. Can strong acids ( such as Nitric, Sulphuric,& Hcl) or
alkalins be used in place of decinormal Hcl.
3. Why is the Hb level high in the new born?
4. What would happen if Hb present freely in the
plasma instead of in the red Cells?
5. Why should ten mins be allowed before diluting the
solution of blood & N/10 Hcl?
22. Test Time
1) Hemoglobin (abbreviated______) is a red substance made of iron and
protein.
Hb
2) Hemoglobin __________ Oxygen to the cells.
Carries.
3) Carries __________away from the cells
Carbon dioxide
23. 4) _______is the iron component of hemoglobin
Heme
5) Each group of heme can carry _____ molecule of oxygen
One
6) Normal hemoglobin is 12 to 16 grams per deciliter (g/dl) in
women T/F
True
24. References
Text book of Medical
Physiology
Guyton & Hall
Hutchinson Clinical Methods
Practical Physiology Manual
A.K. Jain, C.L. Ghai, G.K. Pal
Net source for pictures