1. Chapter 41
Hematology

2. Hematologic Tests Second most common type of tests performed in POL
Cellular components of blood affected by changes in organs or tissues of body
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3. Types of Blood Tests Hemoglobin Hematocrit
White blood cell (WBC) count
Red blood cell (RBC) count
Platelet count
Differential WBC count
Erythrocyte sedimentation rate (ESR)
Prothrombin time

4. Hematologic Tests
Results of tests provide valuable information for diagnosis, evaluating patient’s progress, or regulating further treatment

5. Complete Blood Count Hemoglobin determination Hematocrit determination
WBC count

6. Complete Blood Count RBC count Differential WBC count
Erythrocyte indices

7. Hemoglobin and Hematocrit
Major component of erythrocyte and carrier of oxygen in body; 85 percent of dry weight of RBC
Synthesis of heme requires iron
Adult male requires 0.5 mg/day of iron
Menstruating female requires 2 mg/day of iron

8. Hemoglobin and Hematocrit
Carries 95 percent of oxygen to cells
Transports 27 percent of carbon dioxide back to lungs for removal
Acts as buffer system

9. Hemoglobin and Hematocrit
Separation of blood into liquid portion and solid portion by process of centrifugation
Erythropoietin
Hormone that triggers production of new red cells
Hemoglobinopathies
Group of diseases; abnormal forms of hemoglobin

10. Hemoglobin and Hematocrit
Iron deficiency anemia
Near-normal hematocrit with low hemoglobin value; hypochromic RBC lack hemoglobin
Determining hemoglobin values
Cyanmethemoglobin

11. Hemoglobin and Hematocrit
Normal hemoglobin values or reference ranges by age or sex
Normal hematocrit values or reference ranges by age or sex

12. Hemoglobin and Hematocrit
Microhematocrit
Centrifuge
Packed cell column showing separation of cellular components >>

13. WBC and RBC Counts WBC and RBC counts WBC differential
Automated method
WBC differential
Normal leukocyte counts

14. Leukocyte Identification Guide

15. Leukocyte Differentiation
Groups
Myelocytic or granulocytic series
Lymphocytic
Monocytic

16. Leukocyte Differentiation
Granulocytic group
Neutrophil
Eosinophil
Basophil
Differential leukocyte count
Normal values for a differential leukocyte count in adults

17. Erythrocyte Indices Include: Mean corpuscular volume (MCV)
Mean corpuscular hemoglobin (MCH)
Mean corpuscular hemoglobin concentration (MCHC)

18. Erythrocyte Indices
Provide information about size of RBC and hemoglobin content
Normal values

19. Erythrocyte Indices Using erythrocyte indices to diagnose
MCH and MCV increased in megaloblastic anemias
MCH and MCV decreased in hypochromic and microcytic anemias
MCHC increased in hereditary spherocytosis
MCHC normal in macrocytosis
MCHC decreased in iron deficiency anemia

20. Erythrocyte Sedimentation Rate
Measures rate at which RBC fall toward bottom when placed in vertical tube >>

21. Erythrocyte Sedimentation Rate
Also called “sed rate”
Used in diagnosis and treatment of many diseases
Inexpensive
Accurate
Easy to perform

22. Erythrocyte Sedimentation Rate
Wintrobe method
EDTA venous blood sample mixed
Blood transferred with Pasteur pipette to Wintrobe tube
No air bubbles
Place tube vertically in rack to stand for 60 minutes
Read number of millimeters red cells settled
Normal values for Wintrobe method of ESR

23. Erythrocyte Sedimentation Rate
Westergren method
Mix blood sample with 3.8 percent sodium citrate solution before filling tube
Normal values for Westergren method of ESR
Sediplast ESR system

24. Erythrocyte Sedimentation Rate
Guidelines for Wintrobe and Westergren ESR procedures to measure accurate results
Rouleaux >>

25. Erythrocyte Sedimentation Rate
Using the ESR to diagnose
ESR increased in infections and inflammatory diseases, tissue destruction, and other conditions leading to increased plasma fibrinogen
ESR increased with anemia, menstruation, pregnancy, malignant neoplasms, and multiple myeloma
ESR normal in osteoarthritis, some cases of cirrhosis, and malaria
ESR decreased in polycythemia, spherocytosis, and sickle cell anemia

26. Coagulation Studies Prothrombin Time (PT)
“Protime”
Measures time it takes a patient’s blood to clot
Normal blood clots in seconds
International Normalized Ratio (INR)
Can be universally applied

27. Automated Hematology Instrumentation and Quality Control
Hematology instruments that require sample dilutions
Hematology instruments that do not require sample dilutions

28. Automated Hematology Instrumentation and Quality Control
CLIA ’88 regulation for quality control in automated hematology

29. Automated Hematology Instrumentation and Quality Control
Required procedures
Calibration
Control samples
Proficiency testing
Check manufacturer’s recommendations for particular piece of equipment