Docfan Academy

Cells in a sample keep working, bacteria keep growing, and some substances break down in heat or light. Your job is to deliver the sample to the bench as close as possible to the way it left the patient.

Time and temperature

Every test has its own limits. Some samples must reach the lab quickly. Others can wait, but must be separated, chilled or kept at room temperature. Always follow the test's instructions and your laboratory's SOP. In general terms:

• Send samples to the lab as soon as possible after collection.
• Do not freeze a sample unless the test says so. Freezing can break cells and damage some tests.
• Protect light-sensitive samples, for example by wrapping the tube in paper or foil.
• Never leave samples in the sun, on a window sill or in a hot car. Heat can spoil a result in a short time.

Pack it safely

Use the idea of triple packaging, standard for moving infectious material:

1. A leak-proof primary container: the tube, with the lid tight.
2. A leak-proof secondary container with enough absorbent material to soak up the whole liquid if the tube breaks.
3. A strong outer box or cooler, with sender and receiver written clearly and cool packs if the test needs them.

Keep tubes upright in a rack. Put the requisition forms in a separate pocket, never inside the container with the tubes. Wash hands after handling the box.

Chain of custody

Chain of custody is a written trail: who collected the sample, who packed it, who carried it, who received it, and the time of each step. When you receive a sample, check the labels against the forms, check the condition and the time, and record any problem. If a sample does not meet the rules for its test, say so politely and ask for a new one.