Showing posts with label Clinical pathology. Show all posts
Showing posts with label Clinical pathology. Show all posts

Monday, 20 March 2017

PCV (Hematocrit Method)


            It is proportion of blood cells occupied by the RBCs. It is normally 48% for men and 38%for women. It is considered integral part of a person’s complete blood count (CBC).
Hematocrit stands for hema=”blood” and crit=”judgment”. There are two methods for performing hematocrit method. Indicators of anemia include Hb estimation, RBC count and PCV

                              Microhematocrit and Macrohematocrit Methods:





Interpretation of Results:




Polycythemia and Doping:    
                               
                             Polycythemia and doping can both be detected by PCV at regular intervals. 
                                                 

 Acute and Chronic Blood Loss:
                                                               



Saturday, 18 March 2017

Hemoglobin Estimation clinical pathology

Hemoglobin is a protein present in RBCs for exchange of gases with tissues.  Blood is a specialized type of connective tissue in the form of fluid. It has two components called as plasma and cells.
  • Plasma contains 12 coagulation factors. Serum is formed by the removal of these coagulation factors. Serum is collected in red color vacuotainer. It does not let the blood clot.
  • The ratio of cells in the blood is RBCs, WBCs and Platelets as 500:1:30 respectively.
There are four methods for the determination of hemoglobin in the blood;
  1. Sahli’s method..Outdated
  2. Cyanmet Hb method..Updated
  3. Spectrophotometer
  4. Haden Haussen method
Sahli’s Method of Hemoglobin Determination:

Apparatus:
  • Sahli’s tube which is having red and yellow scales on two sides. Red scale is percentage scale and yellow scale is gram percentage or g/100ml scale.
  • Heamometer which is having two standards.
  • Sahli’s pipette.
  • Error percentage is 3%.


Procedure:

  • In sahli’s tube, take N/10 HCL(1/10th of the original HCL) up to 10th level of scale.
  • In sahli’s pipette, take 0.02ml(20microleter) blood.
  • Add blood from pipette into tube.
  • HCL will cause the lysis of the blood cells and hemoglobin is released.
  • Hb after combining with HCL, forms acid hematin which is of tan color.
  • Put tube in the hemometer and continuously add drops of distilled water and shake with the stirrer until color matches. Then, take the reading.

 Interpretation of the results:

Heam portion of hemoglobin is a porphyrin type pigment and contains iron.


Types of Hemoglobin:


Heam Cycle: