Specimen Handling, Transport, and Processing
Handling, Transport, and Processing tests what happens after collection: bedside labeling, tube stabilization, centrifugation, temperature control, timely separation, chain of custody, and rejection criteria. These steps decide whether a technically good draw becomes a valid result.
Labeling and stabilization
- Label at the bedside immediately with the patient's full name, a second identifier, date and time, and collector initials. Never pre-label tubes or label them from memory.
- Invert additive tubes gently; do not shake. Let serum tubes clot upright at room temperature, commonly about 30 minutes, before centrifugation unless the manufacturer states otherwise.
- Protect photosensitive analytes such as bilirubin from light.
Transport and processing
- Follow test-specific temperature requirements: room temperature, refrigerated, or frozen. Do not freeze whole blood. Some tests require ice water or immediate processing; follow the collection manual.
- Centrifuge balanced, capped tubes at the specified time and relative centrifugal force. Separate serum or plasma promptly to limit glucose consumption, potassium leakage, and other shifts.
- Maintain chain of custody for forensic or legal specimens with sealed containers, signatures, and no documentation gaps.
- Reject unlabeled or mislabeled tubes, wrong tubes, gross hemolysis, insufficient volume, expired tubes, and temperature breaches.
Worked example
A lactate specimen in a gray tube is left on the counter for 45 minutes before processing. Delayed separation allows cells to continue metabolizing and can falsely raise the result. The specimen should have been processed promptly according to policy, often with ice and rapid separation; if the delay is documented, reject and recollect.
Traps that cost marks
- Pre-labeling tubes or labeling after leaving the bedside.
- Refrigerating serum tubes before the clot has formed.
- Shaking tubes or delaying separation.
- Missing a chain-of-custody signature.
- Releasing a grossly hemolyzed or mislabeled specimen.