Processing, Storage and Temperature Excursions

Part of Research Nurse (RN) Training: Specimens and Chain of Custody.

About 2 minutes. Free, in your language, no account needed.

Why this matters

Many samples begin degrading the moment they leave the body. What happens in the next thirty minutes often decides whether the result is real.

Processing is not a laboratory concern that starts after you hand the tube over. It starts in your hands.

Follow the processing instructions exactly

Inversion counts. Time to centrifuge. Speed and duration. Temperature during spin. How many aliquots, into which tubes, at what volume.

These are not preferences. A sample spun late or at the wrong speed can produce a result that looks plausible and is wrong, which is more dangerous than an obvious failure.

If the laboratory manual differs from the protocol, ask. Do not choose.

Storage

Know the required temperature and know where the sample is going. Know what is monitored and how you would find out if it failed.

A freezer alarm that nobody is assigned to answer is not monitoring. Ask who responds out of hours, before you need the answer.

Excursions

An excursion is any period outside the required range. Report it, whatever its length.

Do not decide that ten minutes at the wrong temperature is fine. That judgment belongs to the sponsor or the laboratory, who know the stability data for this assay. You may be right and you cannot know it.

Record the duration, the temperature reached, and which samples were affected.

Shipping

Samples usually ship on dry ice or in validated coolers, with a temperature logger.

Confirm the shipment was collected, and confirm it arrived. A box that sits in a courier depot over a weekend is a common, preventable loss.

In practice

The centrifuge fails mid-spin and the backup is in another department.

You note the time, move the samples to the correct holding temperature, and escalate immediately. You do not spin them forty minutes later and file them as normal.

The laboratory may still accept them with a note. They cannot accept what they were not told about.

What this looks like when it goes wrong

A fridge drifts out of range overnight. The display is read in the morning, reset, and the samples are shipped.

Weeks later the assay results for that batch are inconsistent. Because the excursion was never reported, nobody connects the two, and the site is asked to explain results it cannot explain.

Key takeaways