RBCs Flashcards
What’s the average size of a RBC?
7.74 microns
The smallest caliber blood vessel is ____.
3.5 microns
How does the RBC get through?
The membrane is very flexible;
50% is protein
40% is phospholipids and cholesterol
10% is CHO structures along the membrane surface
Despite it’s flexibility, what maintains its biconcave structure?
Cytoskeleton
What makes up the Cytoskeleton?
- Alpha spectrin & beta spectrin
- Actin attached to glycophorin C in membrane and alpha and beta spectrum in cytoskeleton
- Protein 4.1
- Ankyrin (proteins)
RBCs can be damaged by having defects in the protein structures. List the different morphologies and their causes.
- Microcytic - Iron deficiency anemia
- Macrocytic - liver disease, alcoholism
- Target - iron deficiency, liver disease
- Eccinocyte - post splenectomy
- Fragments - sickle cell
- Teardrop - extramedullary hemapoeisis, spleen, liver
- Basket cell - G6PD deficiency
What are the normal number of cells for males?
4.2 - 5.4 million/mm3
What are the normal number of cells for females?
3.6 - 5.0 million/mm3
When a patient’s posture at the time of blood draw is: seated, standing, recumbent; how does it interfere with the number of cells?
Seated: increase
Standing: increase
Recumbent: decrease
How does the patient’s hydration status interfere with the number of blood cells?
Dehydration will increase concentration
How does age interfere with RBC count?
Increases until 14 years old, then decreases in old age
How does altitude interfere with RBC count?
Higher altitudes will increase count
How does pregnancy interfere with RBC count?
Increased body fluid will dilute RBC count
How do drugs interfere with RBC count?
Increase or decrease
What is primary erythrocytosis?
It’s not secondary to systemic disease; proliferation of blood cells (marrow hyperplasia)
