Collecting a 24 hour urine sample (acid preservative)

The following instructions will guide you through the steps of how to collect a 24 hour urine (wee) sample into a sample bottle containing acid preservative.

Safety precautions

Please be aware:

• the bottle that you have been given contains an acid preservative, which must not be tipped out or thrown away.
• this acid is needed to preserve the chemicals that will be measured in the urine sample so that they do not change in the time between the sample being collected and the time when it is tested in the laboratory.

This acid can be harmful to skin, and so the safety advice below should be followed to minimise the risk of injury

• the bottle must always be kept standing upright, with the cap fastened tightly and securely.
• keep the bottle away from children.
• if any of the acid from the bottle is spilled – dilute this straight away with a large amount of water before mopping this up with tissue or a cloth and throwing the tissue or cloth away in the bin.
• if the acid is splashed onto skin – hold the area of skin that was splashed under cold running water until you are sure that all of the acid has been washed away.
• if the preservative is splashed into the eye – flood (rinse) the eye well with lots of cold water for at least 10 minutes. The patient should then be checked by a doctor for any damage to the eye.
• use a second container to catch the urine sample, such as a jug, and then pour the sample into the 24 hour collection sample bottle.

Never pass urine directly into this bottle, as this could make the acid splash back out of the bottle onto the skin.

Instructions

Make sure to write the patient’s name and date of birth on the bottle before you start.

1. On the morning that collection starts, the patient should get out of bed at the usual time and pass urine (do a wee) into the toilet as normal. So that the 24 hour collection period starts with an empty bladder this first wee of the day should be flushed down the toilet as normal.
2. Now write the date and time onto the collection bottle.
3. Collect all urine passed over the next 24 hours into the sample bottle. The patient should not pass urine directly into the bottle containing acid. Urine should be passed into a smaller container and immediately added from this into the 24 hour collection sample bottle. Please make sure this is a clean container.
4. Finish by emptying the bladder the following morning (at the end of the 24 hours) and collecting this wee into the sample bottle. For example, the collection period might start at 8am one morning, and finish the next morning at 8am.
5. You have now completed the 24 hour urine collection.
6. Now write the date and time the sample collection ended on the bottle.
7. Please make sure that the bottle has the start and finish dates and times written on it.
8. Keep the bottle in a cool place, but not in the fridge.
9. Return the bottle to the Clinical Chemistry Department as soon as possible within 24 to 48 hours of finishing the collection, along with the request form given to you by the doctor.

The department is open from 9am to 5pm, Monday to Friday.