Learning Objectives
1. Understand the terms hematocrit, red blood cells, hemoglobin, buffy coat, anemia, and polycythemia.
2. Understand how the hematocrit (packed red blood cell volume) is determined.
3. Understand the implications of elevated or decreased hematocrit.
4. Understand the importance of proper disposal of laboratory material that comes into contact with blood.
Data
|Total height of blood column (mm)|Height of red blood cell layer (mm)|Height of buffy coat (mm)|Hematocrit|% WBC|
Sample 1 (healthy male living in Boston)|100mm|48mm|1mm|48|1%|
Sample 2 (healthy female living in Boston)|100mm|44mm|1mm|44|1%|
Sample 3 (healthy male living in Denver)|100mm|55mm|1mm|55|1%|
Sample 4 (healthy female living in Denver)|100mm|53mm|1mm|53|1%|
Sample 5 (male with aplastic anemia)|100mm|19mm|0.5mm|19|0.5%|
Sample 6 ( female with iron-deficiency anemia)|100mm|32mm|1mm|32|1%|
· Predict how the hematocrit of patients living in Denver, Colorado (approximately 1 mile above sea level), will compare with the hematocrit levels of patients living in Boston, Massachusetts (at sea level). The hematocrit of patients living in Denver will be higher than the hematocrit of patients living in Boston due to higher altitude in Denver.
· How do you calculate the hematocrit after you centrifuge the total blood sample?
After centrifuging the total blood sample you measure the height of the RBC layer (in mm) and then divide by the height of the total blood sample.
· What does the result of this calculation indicate?
This calculation indicates the percentage of the total blood volume that consists of RBCs.
· What is the significance of the “buffy coat” after you centrifuge the total blood sample?
The “buffy coat” is a layer of white blood cells that separates the RBC layer and the plasma.
· As noted in the exercise overview, the average hematocrit for males is