Funny story… I was working with this guy who is a phlebotomist. He asked if we could draw his blood and do a CBC (Complete Blood Count) on him really quick…
I said sure! (our lab manager believes we should have some perks from working in a lab)
After they drew his blood we put it on our little xs1000i (CBC analyzer). His hematocrit was around 47% … if I can remember right. That is slightly elevated.
So I asked him…”Do you smoke?” He looked stunned.
Sheepishly he confessed…”Every once in a while.” I felt proud that my detective skills had figured that out!
People who smoke typically have a high hematocrit because carbon monoxide from cigarettes is binding to their red blood cells instead of oxygen!!
Your body is saying “give me more oxygen!!!”
Your hematocrit is the percentage of red blood cells compared to liquid that they are floating in…
Your blood is water with proteins, sugar, red and white blood cells floating around to reach your tissues and cells.
The red blood cells deliver oxygen to your tissues… You probably knew that part…
Normal for MEN is 40-50%
Normal for WOMEN is 35-45% …why do you think women have naturally less blood in their body?…think about this…they lose blood every month!
The more red blood cells you have… the easier it is for you to get oxygen for exercise.
So, people that build up endurance for running are building muscle… but they are also producing MORE red blood cells!! …have you ever heard of blood doping?
This picture shows two extreme examples (low and high hematocrits).→
The one on the left has a hematocrit of 11%!!
Typically this is caused by GI bleeding, aplastic bone marrow [your blood is made in your bone marrow! so cool!], internal bleeding from accidents, etc. And to be honest… I don’t know how someone could be alive with a hematocrit that low!!
The tube on the right has a hematocrit of 59%!!! That is super high! You’d think that would give you MORE energy… but truly it will make you feel sluggish. Like you have molasses in your veins.
There is also a disease called polycythemia vera (PV) where the body overproduces red blood cells.
This can cause someone’s hematocrit to be super high! I have seen men with a hematocrit of 64% with PV. The cause is unknown.
In those cases patients need to give regular blood donations to keep it under control.
Pregnant women…by the end of their pregnancy… typically feel tired and sluggish.
Besides carrying a 12 lb. bowling ball on your front… the cause of this is typically a low hematocrit!
Your body grows and adds 1/2 of your blood volume in order to feed the new tissues created (uterus & baby). BUT… sometimes your body doesn’t make enough red blood cells to keep up with that growth… Instead water volume is added and this dilutes your blood.
A pregnant woman will typically have a hematocrit of 28-33%. Her body is saying “give me more oxygen!!!”