Kendro Heraeus Biofuge haemo, Инструкция по эксплуатации

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Operation
36
Measuring the hematocrit value
The hematocrit value is determined after removal of the
rotor cap (see page 20). There are two evaluation me-
thods: reading harp and reading spiral.
Reading harp
The reading harp is the standard accessory delivered
with the centrifuge. To read the hematocrit values, you
must remove the capillaries one by one from the hema-
tocrit dish.
Place the capillary with the lower end of the blood col-
umn on the zero line and the upper end on the 100 %
line of the reading harp. At the boundary between the
erythrocytes and the plasma you can now read the
percentage of packed cells. Be careful to place the the
capillary at right angles to the zero line.
Reading spiral
The reading spiral is available as additional accessory.
To measure hematocrit values, remove the rotor cap
(see page 20) and place the spiral on the hematocrit
dish, which may remain in the centrifuge. Using the
outer knurled (eccentric) screw, turn the zero line so
that it comes to lie on the outer end of the blood col-
umn; then place the 100 % line of the reading spiral
over the meniscus using the knurled screw in the mid-
dle.
You can now read the hematocrit value directly from
above on the graduation. Once you are finished, you
can dispose of all capillaries at once. Loosen the rotor
fastening screw with a coin by turning it counterclock-
wise, lift the hematocrit dish vertically out of the centri-
fuge and eject the capillaries into the waste disposal by
overturning the dish.
General hints concerning hematocrit
measurements
A certain amount of standardization is necessary to
obtain reproducible results, both in the interest of the
patients and blood donors and for the sake of compa-
rability of sciencific data.
The German standard DIN 58933 describes a practical
standard. The procedure outlined in this manual has
been designed in accordance with this standard. We
recommend all users to obtain a copy of it.