Collecting and labelling samples
The right tubes, the right order of draw, mixing, filling and labelling.
Which tubes?
The portal tells you which tubes each order needs when you print the barcodes. Our tubes are colour-coded by their caps:
| Cap | Tube | Commonly used for |
|---|---|---|
| Light blue | Citrate | Clotting tests |
| Gold | SST / serum | Most biochemistry, hormones, vitamins |
| Green | Lithium heparin | Some biochemistry |
| Lavender | EDTA | Full blood count, HbA1c, some genetics |
| Grey | Fluoride oxalate | Glucose |
| Dark blue | Sodium heparin | Trace elements |
You can order more tubes any time from Consumables.
Order of draw
When taking several tubes from one patient, fill them in this order, so additives from one tube can't affect the next:
- Blood cultures (if taken)
- Light blue: citrate
- Gold: serum (SST)
- Green / dark blue: heparin
- Lavender: EDTA
- Grey: fluoride oxalate
Fill and mix
- Fill each tube until it stops drawing. Citrate (light blue) tubes must be filled exactly to the line, or clotting results can't be reported.
- Gently invert each tube straight away, turning it upside down and back. Don't shake.
| Tube | Gentle inversions |
|---|---|
| Light blue (citrate) | 3–4 |
| Gold (SST) | 5 |
| Green, dark blue, lavender, grey | 8–10 |
Label at the patient's side
Label every tube immediately after taking it, with the patient still present, using the barcode labels printed for their order. See Printing barcodes and request forms.
Swabs, urine and stool
Swabs and containers come in several types (culture swabs, PCR swabs, universal containers, stool pots and 24-hour urine containers), and the wrong one can mean the test can't be done. To check which to use, look the test up in Tests List in the portal: it shows the sample, the container and any collection instructions. The Collection Instructions on each order show the same.