An essential part of managing your child’s diabetes is frequently testing their blood sugar levels (also known as blood glucose levels) to help avoid highs and lows – and knowing when to test for ketones. At times, this testing may be difficult – both for you and your child, especially if they’re very young.
- Blood sugar testing
- Ketone testing
- HbA1c test
- Thyroid and coeliac disease tests
- Other diabetes complications
Testing your child's blood sugar
Good diabetes management is important both for your child’s day-to-day health and to help prevent any diabetes-related problems in later life. Regular testing of your child’s blood sugar level is a key part of this.
- How to test blood sugar
- When to test blood sugar
- Testing a baby's blood sugar
- Testing a toddler's blood sugar
- Blood sugar testing tips
- Blood sugar action points
- Blood sugar Q&A
Your paediatric diabetes team will give you a blood glucose meter, used to check your child’s blood sugar levels. Normally, there are a few to choose from and your diabetes team will help you and your child make the right choice. Your meter comes with a finger-pricking device and an initial supply of lancets (to take a drop of blood from the finger) and testing strips (to apply a drop of blood to, in order to get the result). Your diabetes team will also explain to you how to get further free supplies of these on prescription from your GP.
Many parents worry or are anxious about testing their child’s blood sugar levels. Pricking their fingers can be painful, especially at first, and no parent wants to hurt their child. Then there’s the anxiety about what the levels will be. You’ll be told your child’s target levels to aim for, and it can be frustrating and even scary if you’re not meeting these.
How to test your child’s blood sugar levels
- Wash your child’s hands.
- Prick the side of your child’s finger rather than the tip, as this keeps pain to a minimum. Don’t prick too near the nail and don’t prick the index finger or thumb.
- Devices are now available that allow you to take blood from different parts of the body, such as the base of the thumb or the arm. Talk to your diabetes team about the suitability of alternative site meters.
- Insert a test strip into the blood glucose meter – this will turn on most meters automatically.
- Apply a drop of blood to the test strip, and the meter will automatically read the test results. All meters and strips are tested to ensure they’re accurate, but be aware that extreme temperatures can affect meter readings.
- Make a note of all the test results – this will help you and your diabetes team to establish your child’s pattern of blood sugar levels.
- Depending on the type of meter, you may need to calibrate it when you first use a new packet of test strips. Talk to your diabetes team about how to do this.
- You may also need to quality-check your meter from time to time. Again, talk to your diabetes team about this.
When to do a blood sugar test
It’s recommended to test:
- before a main meal
- before bed
- if they feel unwell
- before and after physical activity
- if they feel any hypo warning signs
- any time you or your child feels their blood sugar levels are too high or too low.
Your diabetes team may also ask you to test at other times as well or instead (eg during the night), in order to get an overall view of your child’s diabetes control. If your child has recently been diagnosed, it’s particularly important to test often to get a good idea of what’s happening with their blood sugar levels.
Testing your baby’s blood sugar
With babies, you need to prick their heels, instead of their fingers. Your diabetes team will show you how to do this.
Because your baby can’t tell you how they feel (other than by crying), you’ll probably need to check their levels frequently. Again, your diabetes team will guide you on this.
Testing your toddler’s blood sugar
Getting blood from a toddler can be difficult. Try to get them to cooperate as much as possible: explain what you’re going to do and reassure them that even though it may hurt, it’ll be over quickly. Try pricking teddy’s finger or encourage your child to help if they want to. If you’re finding it difficult, ask your diabetes team for advice
Blood sugar testing tips
- Make sure your child’s hands – and yours – are clean. Use water rather than baby wipes (they contain glycerine that can alter the result).
- Avoid pricking the thumb or index finger – and use a different finger and a different part of it each time.
- Don’t finger-prick the middle of a finger or too close to a nail – this will really hurt.
- Ask your child to hold their hand down towards the ground to make more blood flow to the fingers.
- Make sure your child’s hands are warm – cold hands make it hard to draw blood, and finger-pricking will hurt more.
Blood sugar levels action points
- Ask your diabetes team what blood sugar targets your child should aim for and what to do about high/low results.
- Check with your diabetes team the best times of day to test, and if you need to test at night.
- Make sure you get free testing supplies on prescription – talk to your diabetes team for more information
Blood sugar Q&A
What blood sugar targets should I aim for?
The general target ranges for blood sugar levels are 4–7mmol/l on waking, 4–7mmol/l before meals at other times of the day, and 5–9mmol/l two hours after meals, but your diabetes team may suggest individual targets for your child. Although you shouldn’t expect to achieve these targets all the time, aiming for them will help your child to keep good control of their diabetes.
How important is it to keep a record of my child’s test results?
This is really important, as it helps you and your diabetes team see how well your child’s diabetes control is working. It will also help you and your child make decisions and adjustments between clinic visits. It doesn’t matter if you write the results in a blood sugar diary or record them electronically – the important thing is to havea record of your child’s blood sugar levels that both you and your diabetes team can use.
I’ve heard of continuous glucose monitoring systems (CGM). What are they?
With CGM a small sensor is inserted just under the skin and measures blood sugar levels continuously. Every few minutes, the sensor transmits the blood sugar level to a receiver or an insulin pump. You still need to do finger-prick blood tests, though, to calibrate the sensor and check it for accuracy. CGM aren’t available for everyone, but if you think your child would prefer one, speak to your diabetes team.
Ketone testing
Ketones are poisonous chemicals that can develop if there isn’t enough insulin in the body to allow enough glucose to enter the cells. If ketones are left untreated they can cause the body to become acidic – this is called diabetic ketoacidosis (DKA).
You should check for ketones if your child’s blood sugar level is high – your diabetes team will tell you at what level – or if they are ill. Most children will check their blood for ketones in a similar way to checking blood glucose levels.
Diabetic ketoacidosis (DKA)
DKA can develop:
- when your child is first diagnosed with Type 1 diabetes (some children aren’t diagnosed until they develop DKA)
- when your child is ill
- during a growth spurt/puberty
- if your child hasn’t taken their insulin dose(s).
DKA takes time to develop, so if your child has high blood sugar levels you generally have time to take steps to prevent it. Sometimes, though, it can develop more quickly, particularly in young children and pump users. It has to be treated in hospital, as your child will need a drip and an insulin infusion.
Diabetic ketoacidosis symptoms
- ketones in the blood/urine
- abdominal pain
- nausea/vomiting
- rapid breathing
- a fruity smell on the breath (a bit like pear drops or nail polish remover).
If your child has high blood sugar levels and any signs of DKA, contact your diabetes team immediately. If DKA is picked up early it’s easily treated with extra insulin and fluids, but, left untreated, it could cause your child to become seriously ill.
HbA1c test
A HbA1c test is usually done either at the clinic or before your child’s appointment. This blood test measures diabetes control over a period of two to three months. It is measured in millimoles per mol (mmol/mol).
The recommended level for children is generally 48mmol/mol, but targets are individual and your diabetes team may suggest a different target for your child.
For some people, the HbA1c test may not be accurate, for example if your child has a blood disorder, such as sickle cell anaemia or sickle cell trait. In this case, a fructosamine test is often done, which gives a measurement of diabetes management over the past two to three weeks.
HbA1c action points
- Ask your diabetes team what the target is for your child’s HbA1c or fructosamine test.
- Check with them how often, and where, the test will take place.
- If you know that your child has a blood disorder, tell your diabetes team in case it affects the accuracy of the HbA1c test.
Thyroid and coeliac disease tests
As it’s an autoimmune condition (caused by the body destroying its own cells), Type 1 diabetes is also linked to other autoimmune conditions, such as thyroid problems and coeliac disease. Because this link is well known, your child will also be tested for these conditions.
Thyroid and coeliac disease action points
- Check that your child has had their thyroid hormone levels tested. If they haven’t, talk to your diabetes team.
- Make sure that this thyroid check then happens every year.
- Check that your child has had a test for coeliac disease, and if they show any symptoms contact your diabetes team.
Other diabetes complications
Type 1 diabetes does carry a risk of potential health problems (or “complications”) later on in adult life, such as heart disease or damage to the kidneys, eyes or nerves. It’s natural after diagnosis for parents to fear that their child will develop complications, especially if they know someone with diabetes this has happened to.
However, medical research has shown that these potential complications are much less likely in people who keep their blood sugar levels as close to their target as possible.
This doesn’t mean that you should get anxious or feel guilty if your child’s blood sugar levels aren’t perfect all the time. Nobody with diabetes can always get it right, and short periods of high levels aren’t a problem long-term. Diabetes aside, as a parent, you’ll encourage your child to follow a healthy lifestyle to ensure they get the best start in life. Managing your child’s diabetes is another part of this.
And you’ve got your child’s paediatric diabetes team to help you. At every clinic appointment they will check your child’s height and weight to make sure they’re growing properly, and their general health. And from the age of 12, as well as that every year your child should have blood tests, urine tests, eye screening and a blood pressure check to make sure they’re not getting any health problems because of their diabetes. This is called an “annual review”
It’s really important your child gets these checks and that their diabetes stays as well managed as possible to reduce their chance of getting any diabetes complications later on in adult life. Every year an audit is carried out into all children’s diabetes teams in England and Wales, which highlights the key checks your child should get as a part of their diabetes care. Read the most recent audit at theRoyal College of Paediatrics and Child Health website.