Deciding what is normal and interpreting blood counts Flashcards Preview

Y2 MCD - Haematology - Laz > Deciding what is normal and interpreting blood counts > Flashcards

Flashcards in Deciding what is normal and interpreting blood counts Deck (6)
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1
Q

State some factors that affect what is ‘normal’.

A
Age 
Gender 
Ethnic origin  
Physiological status  
Altitude 
Nutritional status  
Cigarette smoking  
Alcohol intake
2
Q

What is the difference between a reference range and a normal range?

A

Reference Range = derived from a carefully defined reference population e.g. children 5-10 years
Normal Range = much vaguer – it should represent the people that live in the local area and come to the hospital

3
Q

How is a reference range determined?

A

Samples are collected from healthy volunteers with defined characteristics.
The data is analysed by appropriate techniques.
If the data follows a normal (Gausian) distribution, you can determine what is normal by taking the mean and taking 2 standard deviations on either side. Between the 2 SDs on either side, you will have 95% of the data.

4
Q

What unit is MCV measured in?

A

Femtolitres (10^-15L)

5
Q

What unit is MCH measured in?

A

Picograms (10^-12g)

6
Q

How are these parameters measured now?

A

It is determined indirectly by light scattering or by interruption of an electrical field