Iris Sample Processing StatSpin® CritSpin Microhematocrit System - Manual (Page 12)

8
Section
5
Determination of Packed Red Cell
Volume (Microhematocrit)
Both glass and plastic micro-capillary tubes are available. Product Number HT9H(glass) &
HP8H(plastic) have been pretreated with heparin and should be used for capillary blood. They
should be stored in a cool dry place. Product Number HT9U(glass) & HP8U(plastic) are untreated
and used for venipuncture (anticoagulated) samples.
For glass tubes only: if the vial of tubes is new, unscrew the top, remove and discard the foam
cushion and reattach the top. Now a single tube at a time can be shaken from the vial through the
small hole in the center of the cover.
Procedure for packed red cell volume (microhematocrit)
1a. Capillary ("fingerstick") blood - prepare a skin site and lance. Use heparinized tubes, Product
Number HT9H or HP8H.
or
1b. Venous blood - take well-mixed anticoagulated blood from a syringe or a vacuum blood
collection tube. Use untreated tubes, Product Number HT9U or HP8U.
2. Hold the micro-capillary tube by the end with the color-coded band. (See Figures, page 10)
3. Fill to the color-coded band. Remove from sample and tilt the banded end downward until the
blood moves half-way between the band and the end of the tube.
4. Hold the tube in a horizontal position and push the dry (banded) end of the tube fully into the
vertically held sealing compound. Twist and remove.
5. Using a laboratory tissue wipe off any blood that is forced from the other end.
6. Put the tube, sealed end towards the outer rim, in any of the twelve positions on the
Hematocrit Rotor, RH12. This rotor need not be balanced. Screw cover in place.
7. Holding the rotor by the black "cover knob", attach the rotor to the rotor-holder.
I MPORTANT : Always hold hematocrit rotor by the black knob on the rotor cover, when pressing
it firmly in a downward motion onto the rotor-holder and when removing the rotor from the
centrifuge. Pressing on the outer edges of the Hematocrit Rotor, RH12, may result in damage
to the rotor.
8. Centrifuge the Hematocrit Rotor.
9. After the rotor stops, remove the rotor. To read hematocrit, place the rotor into the middle of
the illuminated, digital reader. Follow directions printed on the reader.
10. Spun tubes inside the Hematocrit rotor can also be read with the circular reader, HR4C as well
as removed from the rotor and read with the card-style reader, HR05.
Quality Control
1. The Quality Control procedures established for your laboratory should be followed.
2.
To verify the adequacy of cell packing, on a daily basis, select one or more tubes,
(preferably with a hematocrit over 50), centrifuge and read. Spin these tubes a second time.
The difference between the initial reading and the second reading should be 1 percent or
less.