1. Chapter 9 Hemoglobin, PCV, and Erythrocyte Indices
Hematology Unit 2
Chapter 9
Hemoglobin, PCV, and Erythrocyte Indices
Copyright © 2015 by Mosby, an imprint of Elsevier Inc. All rights reserved.

2. Complete Blood Count CBC includes Total RBC count PCV
Plasma protein concentration
Total WBC count
Blood film examination
Differential WBC count, RBC and leukocyte morphology
Reticulocyte count if anemic
Hemoglobin concentration
Erythrocyte indices
Copyright © 2015 by Mosby, an imprint of Elsevier Inc. All rights reserved.

3. Packed Cell Volume (PCV)
Percentage of whole blood composed of RBCs
Microhematocrit tubes
Red ring – heparinized
Blue ring – not treated
Copyright © 2015 by Mosby, an imprint of Elsevier Inc. All rights reserved.

4. Packed Cell Volume (cont.)
RBC – high specific gravity
Dark red layer
Buffy coat
Whitish-gray layer above the RBC layer
Consists of WBCs and platelets
Height – rough estimate of total WBC count
Plasma
Clear to pale yellow fluid
Top layer
Copyright © 2015 by Mosby, an imprint of Elsevier Inc. All rights reserved.

5. Packed Cell Volume (cont.)
Plasma layer
Normal – clear to pale yellow
Cloudy – lipemic
Reddish tinge – hemolyzed
Deep yellow – icteric
Copyright © 2015 by Mosby, an imprint of Elsevier Inc. All rights reserved.

6. Packed Cell Volume (cont.)
Hematocrit reading tube
Copyright © 2015 by Mosby, an imprint of Elsevier Inc. All rights reserved.

7. Packed Cell Volume (cont.)
Significance of results
Pathologic condition
Below normal
Anemia
Inadequate volume of blood to anticoagulant ratio
Above normal
Polycythemia
Dehydrated
Copyright © 2015 by Mosby, an imprint of Elsevier Inc. All rights reserved.

8. Plasma Protein Concentration
Plasma from the hematocrit tube
Refractometer
Measured in g/dL
Lipemic samples
False increase in the total protein reading
Copyright © 2015 by Mosby, an imprint of Elsevier Inc. All rights reserved.

9. Hemoglobin Testing Functional unit of the RBC Heme portion Globin
Contains iron
Globin
Amino acids
Synthesis during maturation of RBCs
Different forms
Oxyhemoglobin – oxygen replaces CO2 in respiration
Methemoglobin – occurs naturally
Sulfhemoglobin – results from cell aging
Copyright © 2015 by Mosby, an imprint of Elsevier Inc. All rights reserved.

10. Erythrocyte Indices Help classify anemia
Provide an objective measure of the size and average hemoglobin concentration
Accuracy dependent upon:
Total RBC count
PCV
Hemoglobin concentration
Compare values to morphologic features
Copyright © 2015 by Mosby, an imprint of Elsevier Inc. All rights reserved.

11. Mean Corpuscular Volume
MCV measures average size of RBCs
Divide PCV by RBC concentration and multiply by 10
Example:
Dog has a PVC of 42%, RBC count of 6.0 million/mL
42/6 x 10 = 70 fL (femtoliters)
Copyright © 2015 by Mosby, an imprint of Elsevier Inc. All rights reserved.

12. Mean Corpuscular Hemoglobin
Mean weight of hemoglobin contained in the average RBC
Divide the hemoglobin concentration by the RBC concentration and multiply by 10
Example:
Hemoglobin concentration of 14 g/dL and RBC concentration of 7 million/mL
14/7 × 10 = 20 pg (picograms)
Copyright © 2015 by Mosby, an imprint of Elsevier Inc. All rights reserved.

13. Mean Corpuscular Hemoglobin Concentration
Concentration of hemoglobin in the average RBC
Divide the hemoglobin concentration by the PCV and multiply by 100
Example:
Hemoglobin concentration of 14 g/dL and PVC of 42%
14/42 × 100 = 33.3 g/dL
Copyright © 2015 by Mosby, an imprint of Elsevier Inc. All rights reserved.

14. Summary Cell counts Packed cell volumes Plasma protein concentration
Hemoglobin testing
Erythrocyte indices
MCV
MCH
MCHC
Copyright © 2015 by Mosby, an imprint of Elsevier Inc. All rights reserved.