What is a finger prick blood test?
A finger prick blood test is a convenient way of testing that enables patients to collect a blood sample in the comfort of their own home. It requires a tiny cut to be made in the end of the finger before letting the blood drip and collect in the sample container. The patient can then seal the container before returning it to the laboratory for testing.
in total the procedure takes about 15 minutes, but there are a number of things that you’ll need to remember when carrying out a finger prick blood test. We talk you through the details in this blog.
What is included in the kit?
The finger prick blood sample collection kit may vary slightly depending on the test that you take. However, it will usually contain the following elements: –
- 3 x Safety Lancets to prick the finger
- Cotton wool, plaster and alcohol wipe
- Mini collect vial in protective case
- Request form
- Prepaid Envelope
How do you collect a finger prick blood sample
Although each brand is different, our finger prick blood samples can be collected using the following instructions.
- Opening containers and packaging can be tricky once you’ve cut your finger so it’s worth laying everything you need on the table.
- Before you begin, wash your hands thoroughly with warm soapy water and dry with a clean towel. It is much easier to collect the sample if your hands are warm so feel free to run your hands under the tap longer than needed.
- The ribbed area around the vial top indicates the cap opening location. Remove the cap by applying gentle pressure on the cap in an upward direction. Most finger prick vials are the same even if the brand is different.
- Safety lancets differ by brand, but the majority will only be useful for one try. The instructions below are relevant to the safety lancets supplied with our COVID-19 home test kit.
- Pull the yellow tab from the bottom of the safety lancet. The lancet is now ready to use.
- Some people find the best site to collect a sample from is from the side of the little finger and whilst standing up.
- Using the alcohol wipe, clean the tip of the selected finger. Ensure the finger is completely dry to ensure a successful collection. Blood will not form a droplet if the finger is not completely dry.
- Position the safety lancet across the run of epidermal ridges on the side of the selected finger. Hold against the skin firmly.
- Press the white button at the top of the safety lancet – this will then activate the lancet.
- Gently apply pressure to the tissues surrounding the puncture site – this will encourage the blood to flow.
- Discard the first drop of blood by wiping away with the cotton wool provided.
- Hold your hand/arm downward and firmly massage the side of the hand down the finger to encourage the blood to flow.
- Position the finger over the collection vial so blood drops into the scoop. Be patient and allow the blood to form a droplet that drops into the vial, it will be quicker and more effective this way. The blood should flow easily from the scoop down the vial walls and into the vial.
- Continue massaging the hand down to the little finger until the blood reaches the upper fill line of the vial. If there is insufficient sample the lab will not be able to perform the test which may result in extra charges.
- If blood flow stops, try wiping the puncture site with a clean, dry tissue. Wait 5 to 10 seconds and then the blood flow should resume.
- If insufficient sample is collected from the first puncture site, use one of the two remaining safety lancets on another finger/hand and repeat the process until the required amount of blood is collected
- Once you have filled the vial to the top fill line, or even above this, close the tube with the original cap. An audible ‘click’ indicates correct closure.
- Immediately after closure it is important to gently shake the sample so that the blood flows to the top of the tube and to the bottom. This will spread the chemicals within the tube to preserve the blood during transit to the lab.
- Complete the label on the side of the vial to include your forename, surname and date of birth. These details MUST correspond with what is completed on the request form sent in the package.
- Place the labelled tube inside the original protective case and press closed.
- Place your mini collect vial in the protective case, inside the prepaid envelope along with your completed request form.
- Seal the prepaid envelope and post it back to us in any Royal Mail post box.
- If you have any queries, please contact us for assistance.
Always shake the sample
When you deposit any blood sample, there is a chemical serum in the vial which preserves the blood and prevents it clotting. Due to the fact that a finger prick blood sample takes longer to deposit than a standard sample, it’s important that you shake the vial once it’s full. This will ensure that it can be tested once it reaches the laboratory. The sample should be liquid when you send it.
Other tips to remember
Although a finger prick blood sample is completely safe and effective in the same way a normal blood test is, there are few additional things you’ll need to remember.
- Always wipe the envelope down once you’ve collected the sample for hygiene purposes in case any blood has smeared on it
- Ensure you include any paperwork in the envelope when you send it and complete the label on the vial. Without this, the laboratory will not test it
- Bear in mind postal service times may affect the quality of your sample. If you deposit on a Friday or bank holiday it may be sitting in the post box over the weekend.