Ketones, serum; ketones, blood
This blood test measures ketones, a byproduct of digestion, in your blood. When you have a high level of ketones in your blood, it's called diabetic ketoacidosis (DKA). DKA is a complication of diabetes that can be fatal if it's not treated.
When you have diabetes, your body doesn't make enough insulin, a hormone that regulates the metabolism of fat and carbohydrates. Or it can't properly use insulin to break down the food you eat. When your body doesn't have enough insulin, it breaks down fat for energy instead of glucose, or sugar. The breakdown of fat produces ketones, which can build up in your blood and spill over into your urine if your diabetes is not under control. If your ketone levels are too high, it could cause you to go into a diabetic coma.
You might have this test if you have symptoms of DKA. These include extreme thirst, tiredness, vomiting, trouble breathing, a fruity odor on your breath, high blood sugar levels, and high levels of ketones in your urine. You can test for ketones in your urine with test strips.
Your healthcare provider might order blood glucose levels to see if your diabetes is out of control. You might also have a urine test to check for ketones in your urine.
Your healthcare provider also might order an electrocardiogram, or EKG, which checks your heart's electrical activity. DKA can affect the heart.
Your healthcare provider might also order an arterial blood gas (ABG) test to check the acid-base levels of your blood. A buildup of acid in the blood stream would cause these levels to be very abnormal.
Many things may affect your lab test results. These include the method each lab uses to do the test. Even if your test results are different from the normal value, you may not have a problem. To learn what the results mean for you, talk with your healthcare provider.
A normal test result is negative and means you have no ketone bodies in your blood. If you test positive for ketones, it could mean your diabetes is not under control. You could have DKA.
People who do not eat enough calories can also develop high levels of ketones. This includes people with alcoholism, and those with an eating disorder or malnutrition from a severe illness such as cancer.
The test requires a blood sample, which is drawn through a needle from a vein in your arm.
Taking a blood sample with a needle carries risks that include bleeding, infection, bruising, or feeling dizzy. When the needle pricks your arm, you may feel a slight stinging sensation or pain. Afterward, the site may be slightly sore.
Certain diets, such as a high-protein diet or a one that is high in fat and low in carbohydrates, also can cause increased ketones in your blood. Drinking large amounts of alcohol also can affect your test results.
You might also have a high level of ketones in your blood if you have diabetes and you're sick with a cold or the flu.
You don't need to prepare for this test. But be sure your healthcare provider knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illicit drugs you may use. Some, such as diuretics and blood pressure medicines, can lead to a false-positive ketone test.