Great Ormond Street Hospital for Children NHS Foundation Trust: Information for Families
INR tests at home for warfarin The International Normalised Ratio (INR) test measures how long it takes for the blood to clot. INR tests are a vital part of treatment with anti-coagulants such as warfarin. Some families may be able to do these INR tests at home, so avoiding regular trips to Great Ormond Street Hospital (GOSH) or their local hospital. This information sheet explains about carrying out INR tests, reporting results and what to do next. It should be read in conjunction with the information booklet provided by CoaguChek®, which is the machine used by GOSH.
What is an INR test and why is it important? INR test results are used to make sure that
Ideally the INR should be within the
the dose of warfarin is giving the right
range given and every time your
amount of anticoagulation. Having too
child has an INR, the dose could be
much warfarin can cause bleeding as the
increased, decreased or remain the same
blood becomes too thin and having too
depending on the result. Each time, your
little means that the blood will remain
anticoagulation contact will make sure
too sticky and at risk of clotting. Your
you understand how much warfarin to
child will be given a ‘target INR range’
give your child.
by the staff looking after your child. This target INR varies from child to child depending on his or her condition. Your child’s target INR will be written in his or her warfarin record booklet.
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© GOSH NHS Foundation Trust January 2015
Can everyone do INR tests at home?
Carrying out a test
No, it is not suitable for everyone. At
Contacting the team for dosing changes
GOSH, we will only recommend doing INR
We will also ask you to confirm that you
tests at home if your child:
have learnt these skills by signing a record
has an agreed training plan between
form in your teaching information pack.
your family and the nursing team you have completed a training package has attended all scheduled INR tests and clinic visits If your child fits in to this category, please
Understanding the results
A copy of this form will be sent to all healthcare professionals involved in your child’s care. Remember that we will make sure that you are confident in doing your child’s INR tests before you go home.
talk to us about the possibility of doing Once we have agreed that you and your
How do I do an INR test with the CoaguChek®?
child can do the tests at home, we need
Full information about doing an INR test
to liase with the doctors and nursing
is included with the CoaguChek® device
team in your local area to confirm that
but the main points follow. Remember
they support home INR testing. If this
that with some children, it is easier to get
is the case, we will then need to talk
a blood sample from their foot rather
to your family doctor (GP) to confirm
than fingers. We will show you the best
prescription of the supplies needed for
way for your child.
the CoaguChek machine, testing strips
1. Make sure you have all the equipment
INR tests at home.
®
and warfarin medication.
you need ready • CoaguChek® machine
Learning about the CoaguChek® machine Before you go home with the CoaguChek® machine, we will teach you how to use it safely. You will need to watch a DVD about the machine and read the written information produced by the
• Results booklet and pen 2. Wipe the area clean and wash your hands 3. Ask your child to wash his or her hands in warm water and dry them 4. Ask your child to shake his or her arms
manufacturer. You will be given the DVD
and wriggle his or her fingers (or toes if
and information to keep. The main things
this is where you will take the sample)
we will teach you are listed below. Preparation of the equipment Quality assurance of results Safety Sheet 2 of 5
• Test strip
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5. Insert a test strip into the meter, which will switch on automatically 6. Confirm strip code and wait for the strip to warm up © GOSH NHS Foundation Trust January 2015
7. Prick your child’s finger (or toe) with the lancet and put a drop of blood on the test strip 8. The meter will tell you if you have put enough blood on the test strip 9. The meter will tell you if the INR test
What do I do with the results? We will advise you how often to do an INR test as this varies from child to child. If you are doing routine testing once a week, try to do the test during office
has been done correctly and give you
hours so that you can discuss the result
the result in a couple of minutes
with your anticoagulation contact. When
10. If your child’s target INR has been
you have done a test, you should ring
programmed into the machine and the
your anticoagulation contact with the
result is outside this range, the meter
test result. They will then check whether
will tell you
your child’s warfarin dose is correct. If
11. The meter stores up to 100 results automatically 12. Record the result in your yellow
you do need to change the dose, they will check that you understand how to take the new dose of warfarin.
warfarin booklet Remember that once you have pricked
Quality Control
your child’s finger, you only have 15
Please bring your CoaguChek® machine
seconds to put the blood sample on
to any appointments/admissions to carry
the test strip before it starts to clot.
out a test as usual. Sometimes an extra
If you run out of time or the machine
sample of the blood for testing in the
tells you that the sample is not big
laboratories may be needed. This extra
enough, you will need to start again
sample can be taken from the same
with a new test strip and pricking
finger but needs to be done within a few
another of your child’s fingers.
seconds of the CoaguChek® sample.
Parents have told us that using distraction techniques and rewarding testing can help children cope with the finger pricks. For more information about these, please see our Distraction therapy booklet available on our website or from the Pals office. Patients on warfarin will be invited for a
The machine is sensitive to heat and moisture, so store it in a warm, dry place away from direct sunlight. Everything you need to carry out INR
six-monthly review coinciding with clinic
tests at home is included in the storage
attendance and general review. Patients
bag so do not put it in another container.
with reduced oxygen saturation may require assessment three-monthly.
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Storing your CoaguChek® machine
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Keep the machine and equipment out of reach of children.
© GOSH NHS Foundation Trust January 2015
Cleaning your CoaguChek® machine
How do I order new supplies?
Put your used lancets and test strips in
Once you have the CoaguChek® meter,
a sharps bin. Your family doctor (GP)
you should be able to get all the supplies
or community team or anticoagulation
needed on prescription from your family
contact should provide this for you and
doctor (GP). An order form is included in
arrange disposal when full.
your information pack. If you have any
After use, wipe the CoaguChek® machine over with a clean cloth,
difficulty getting supplies on prescription, please tell us.
dampened with warm water and a little
For anticoagulation advice and dosing of
washing-up liquid, before drying with
warfarin from INR results, please call 020
another clean cloth
7405 9200 ext. 5774.
If blood gets inside the test strip guide, you will need to remove this part carefully for cleaning. This will be demonstrated during training and the instructions are given in the CoaguChek® user manual provided with the machine Notes
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© GOSH NHS Foundation Trust January 2015
Important information Child’s name Date of birth GOSH hospital number NHS number GOSH consultant Local consultant paediatrician Local consultant haematologist Diagnosis Operation date Date warfarin started Therapeutic range
Get urgent help if INR is less than 2 or more than 7
Frequency of testing when INR is unstable Frequency of testing when INR is stable Length of time to stay on warfarin Initial treatment managed by Ongoing treatment managed by Name of anticoagulation contact Telephone number of anticoagulation contact Name of hospital contact Telephone number of hospital contact Serial number of CoaguChek® machine Roche website: www.coaguchek.com/uk/?target=/en/patients Compiled by the Haematology, Cardiology and Neurology departments in collaboration with the Child and Family Information Group Great Ormond Street Hospital for Children NHS Foundation Trust, Great Ormond Street, London WC1N 3JH www.gosh.nhs.uk Sheet 5 of 5
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© GOSH NHS Foundation Trust January 2015