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Flashcards in full blood count Deck (13):
1

packed cell volume

haemoatocrit
(PCV) is a measurement of the proportion of blood that is made up of cells. The value is expressed as a percentage or fraction of cells in blood.

2

benefits of autmation

capacity
cost
time
precison
accuracy

3

two methods of automation of cell counting

aperture imedance
optical

4

what is aperture imedance counter

particel cell counter
cells in isoltonic solution
-cells pass through aperture and displaces volume affecting electrical current in system

5

what info does impendance aperture giev

mangitue of pulses equates of volume of cells
number of impedance chanes equates to concetration of particles

6

problems with basic aperture impedance counting

shear force near aperture can deform cells
sizing is infeucned by orientation of cells
cannot count mixed populations of cells

7

what is sheath stream focussing

stream of separate cells focussed on a counting zone to better size and count cells in a mxed pop

8

how can you differentiation WBC

on their size on the grah read out
granulocytes are largest

9

what is differential lyis

technique to selectively lyse different populations of WBC to be then used in aperture impedance and optical counting

10

optical cell counting

number of pulses through the system proportional to cell count
narrow forward scatter i cell vol
wide angel scatter is refractive index

11

ESR

erythrocyte sedimentation rate
accessory test fir FBC
non specific test now automated

12

use of ESR

RBC form roulaeux and sedement
can be used to detect soe conditions such as acute phase reactants

13

ESR ormal range

0-20mm in 1 hr
degree of sedementation infleunced by:
- inflamation, sepsis, malignancy,immungolbuil levels