What are ketones?
Ketones (sometimes called acetone) are chemicals which
appear in the blood and urine when body fat is being broken
down for energy. Fat is burned by the body when there is not
enough insulin to allow sugar to be burned for energy.
Ketones also are formed when not enough food has been eaten
to provide the energy the body needs.
Why do I need to test my child for ketones?
Ketone testing is very important because ketones can build
up in the body and result in an emergency condition called
ketoacidosis. Ketoacidosis is a serious, life-threatening
complication of high blood sugar and must be treated
immediately. Ketoacidosis is the number one reason for
hospitalizing children in the U.S. with known diabetes.
Families are usually taught how to do the urine ketone test
on the first day their child has been diagnosed with
diabetes. They may later switch to doing blood ketone
checks. Frequent ketone tests are important in the first few
days after diagnosis to check if enough insulin is being
given to turn off ketone production.
When should I test for ketones?
A method of testing for ketones must be kept in the home
(and taken on trips) at all times.
Ketones must always be checked if your child:
has high blood sugar above 240 mg/dl (13.3 mmol/L) after
fasting
has high blood sugar above 300 mg/dl (16.6 mmol/L) during
the day
feels sick or nauseated (especially if he vomits, even
once). If the child is sick, ketones can be present even
when the sugar is not high.
Children who have been recently diagnosed with diabetes
usually need to check ketones twice a day (or more often if
the test is positive). After the first or second week, if
all ketone checks are negative, you can stop routine testing
of ketones.
Children who take only 1 insulin injection per day should do
a routine morning ketone test to check if their insulin is
lasting a full 24 hours. Ketones will usually be present in
the morning if an insulin injection is needed in the
evening. If the morning blood sugars vary between very high
and very low values, check the ketone level in the morning.
Morning ketones can be a sign of a low blood sugar during
the night followed by rebounding or bouncing back to a
normal or high level by morning.
How do I test for ketones?
You can check for ketones in the urine or in the blood.
Record the result of the ketone test in a notebook so that
it is not forgotten.
Urine Tests
To check for urine ketones you can use urine test strips.
Some commonly used strips are the Ketostix or the Chemstrip
K. The strips are only good for about 6 months once the
bottle of strips is opened. There are some strips that come
individually foil-wrapped that will last 2 to 3 years. Ask your
pharmacist about types of ketone strips available.
If your child is not yet toilet trained, it is usually
best to press a test strip firmly against the wet diaper. It
is also possible to place a cotton ball in the diaper near
the urinary opening. Drops of urine can then be squeezed
from the cotton ball.
Follow the package directions for testing carefully. Urine
ketone tests must be timed exactly using a watch or clock
with a second hand. Have 2 people time and read the strip.
This prevents errors due to color blindness or other
factors.
Blood Tests
To check for ketones in the blood you use a meter (such as
the Precision Xtra meter) and blood ketone strips. For
older children, the blood ketone test is often preferred.
Your provider can show you how to use the meter for
measuring blood ketones.
Tests for checking ketones are available at your local
pharmacy.
When should I call my child's health care provider?
Call your diabetes care provider IMMEDIATLY (day or night) if:
Tell the person answering the phone that the call is urgent.
Your provider will probably have your child take extra
insulin to help make the ketones disappear. If the ketones
are not detected early, particularly during illness, they
will build up in the body and your child will get
ketoacidosis. It is the early detection of ketones and
treatment with extra Humalog or NovoLog insulin that
prevents hospitalizations for ketoacidosis.
Call your diabetes care provider during office hours if:
