Blood sample handling

EHES Training Materials

Equipment • Centrifuge• Empty tubes for re-

centrifugation (only needed if gel serum tubes are used)

• Storage tubes• Pipette• Storage boxes• Disposable gloves

Before centrifugation of blood tubes

• After blood drawing store the tubes at room temperature in a vertical position at least 30 minutes for the blood in serum tubes to be clotted.

• Do not prolong the waiting time over 60 minutes!

• Adjust centrifuge speed 2000-2200 g RCF

Centrifugation of blood tubes (1/2)

• After the waiting period, centrifuge• The serum tube• The fluoride-citrate tube• The 1st EDTA tube

• Do not centrifuge the last two EDTA tubes designated for HbA1c and DNA extraction!

Centrifugation of blood tubes (2/2)

• Place the serum tube and the fluoride-citrate and the 1st EDTA plasma tube in the centrifuge

• Check that all tubes are resting on the bottom of the centrifuge rack

• Check that the centrifuge rotor and tubes are in balance.

• Centrifuge the tubes 2000 g for 10 minutes at room temperature

Sample handling after centrifugation

• After the centrifugation, check that the serum is separated properly

• Pour the serum from the 2 serum collection tubes into the pooling tube, mix gently by swirling the contents• Note! If one of the serum

tubes is haemolysed, do not mix them together

Labelling storage tubes

• Place the storage tubes in a tube rack according to the pipeting scheme

• No need to label all tubes if blood collection is incomplete

• Place the bar code labels in an upright direction, so that the scale marks remain visible

Handling blood collection tubes with gel

• The temperature during centrifugation should be at least 20-22 °C

• Inspect the gel tube after centrifugation for: • Gel surface horizontal• Serum and cell layers

separated clearly• No red cells visible on top

of the gel• No fibrin strands in the

serum• Serum liquid, not clotted

Hemolysed samples

• Do not pool a hemolysed serum sample with non-hemolysed samples

• Several hemolysed samples can be pooled

• Document hemolysed aliquots

• Use the colour guide to document the degree of hemolysis

Pipette aliquots into storage tubes

• 2 x 1,5 ml serum from the pooling serum tube into the 3 ml plastic tube and 1,5 ml aliquots into the 1,5 ml storage cryotubes

• 2 x 1 ml from fluoride-citrate plasma tube into two 1,5 ml cryotubes

• 2 x 1,5 ml from the EDTA tube into two 1,5 ml cryotubes

• Close the cryotubes with caps and freeze the tubes at once

Transferring storage tubes into freezers

• Place the tubes without delay into the boxes in the freezer

• Label boxes before placing them into the freezer because labels will not stick on a wet/cold surface

Sample shipment

• To the national HES laboratory• In dry ice• Packed in leak proof secondary packaging

• To the EHES Reference Laboratory• Packed according to the IATA regulations,

according to Pecking Instruction 650 for diagnostic specimens

• Place one tube upside down in every box

RecordingRecord: • The amount of the collected

serum and plasma• Visible attributes (haemolysis,

lipemia, icterius)• Deviations from the sample

handling protocols, if any• Your initials/personnel code to

identify who handled the samples

Acknowledgements

• Slides• Laura Lund, Päivikki Koponen

• Photographs• Hanna Tolonen

• Demonstration• Saara Vallivaara