Deciding what is normal and interpreting blood counts Flashcards
What is the difference between a normal and reference range?
Reference ranges are very carefully crafted from healthy individuals-defined for specific groups of people
Normal ranges are usually loser based on large amounts of population
Usually tries to account for 95% of the population
But ofc these ranges can vary a lot based on age, gender, ethnicity, pregnancy, altitude, nutritional status, cigarette
Are all measures in the normal ranges normal? Or abnormal if out?
No-if patient just had a massive bleed, shouldnt be normal
and sometimes, patients have abnormal parts
Or sometimes, even within the 95% can be bad-health related range
ideally theyd be totally seperate but impossible
What are the main factors youd look at first in a full blood count?
WBC (and differential), Hb, MCV and platelet count (packed cell volume-old name for Hct)
How do we count RBC, WBC and platelets? Hb?
Counted in large automated instrument-flow cytometer
Hb-pretty much spectrophotomerty
What is the difference between MCH and MCHC?
One is dependent on the cell size (MCH)-so smaller cell would have less MCH natrually-but MCHC woulnt change
MCH tends to parrallel MCV
What are the steps to interpreting WBC count?
Too many or too little? Which cell exactly?
Look in history-is he having infection? then normal high
Then are cells normal maybe
What are the steps to interpreting RBC count?
Aneamia or not? look at hisroty lol
What would be abnormal in Polycythaemia in a full blood count?
Raised everything RBC related-
CAn be caused by pseudo-reduced plasma volume
But usually true poly-increased RBC
-> caused by blood doping/Overtransfusion, Normally increase erythropoeted, Innapropriate erythropoetin (can be neoplastic kidney), independent Erythropoetin
What are some clinical signs of Polycythamia?
Splinomegaly, abdominal mass, cyanosis (then the rest is TBC comparaison with GENDER and AGE appropriate ranges)
