What does hematocrit measure? Why is that info valuable?
% of RBCs in blood
RBCs transport O2 so higher hematocrit the more RBCs available to carry O2
Would an individual suffering from aplastic anemia have higher or lower hematocrit than normal? Why?
Lower hematocrit b/c the bone marrow doesn't produce enough blood cells
What does sedimentation rate measure? Why is that info valuable?
The rate at which RBCs settle out the plasma when placed in a test tube
Some conditions identified by abnormal coagulation of RBCs (clump together)
Ex. myocardial infarction cause higher ESR
ESR for the menstruating female
ESR increases b/c of the loss of iron during menstruation
If patient complaining of chest pain, why might doctor order a ESR?
To see if the person is just experiencing chest pain or if they are having a heart attack
ESR is elevated during a heart attack (myocardial infarction)
What does a hemoglobin (Hb) test measure? Why info valuable?
Measures how much Hb is in RBCs
Useful for determining classification & causes of anemia
Does a male w/ polycythemia have a normal PCV to Hb? Do you think his RBCs contain enough Hb molecules? Why?
Yes, because there's increased RBCs & increased Hb so ratio is normal (3:1)
Why would you look at the PCV/Hb ratio?
If looking just at RBCs & there's an increase you may think there's a problem, but if Hb is increased then it's okay
What does blood typing measure? Why is info valuable?
Blood type determined by presence or absence of antigens A & B attached to surface of RBCs
It is important to prevent mismatch of blood transfusions
What antigen is present in blood if antibody A causes agglutination?
Why is type O considered to be the "universal donor"?
There are no antigens
What blood type is the "universal recipient"?
Reduced O2 carrying ability of blood
Can result from low Hb or low RBC count