HemoCue WBC, Operating Manual

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42
When a capillary skin puncture is performed, several
defense systems in the body are activated very quickly.
These defense systems cause an increase in the number
of WBCs in the blood closest to the wound, leading to
greater differences in results from several samples taken
from the same finger stick.
A study was performed, on the HemoCue WBC system in
which possible influences of capillary sampling technique
were included, see Figure 3 below.
Figure 3
Capillary Sampling Technique
An additional study has been performed at a clinical
reference laboratory in the U.S. including a large number
of blood samples in order to evaluate the HemoCue WBC
system for expected demographic variations (age, gender,
geographics) in the population, see Figure 4 below.
Figure 4
Demographic Sample Population
H
em
o
C
u
e W
B
C
, x
10
9
/L
Sysmex XS-1000i, x10 9 /L
------- X = Y
Coefficients
b
0
= 0.066
b
1
= 1.033
r 2 = 0.972
N = 119
H
em
o
C
u
e W
B
C
, x
10
9
/L
Beckman Coulter, x10 9 /L
Coefficients
b
0
= – 0.451
b
1
= 0.970
r
2
= 0.994
N = 178
------- X = Y