Low blood glucose levels usually have warning signs such as shaking, sweating and rapid heartbeat, but high blood glucose levels can be silent until things start to get out of control.
The staff in the Joslin Pediatic Clinic has this advice.
One of the vital warning signs of an impending diabetic crisis is the appearance of ketones in the blood or urine. For children with type 1 diabetes and their parents, understanding the role of ketones in a diabetic emergency and knowing how to check for them and what to do if your child has them can mean the difference between a good night’s sleep and many tense hours in the emergency room. (Ketoacidosis almost always occurs in people with type 1 diabetes)
Too little insulin for too long a time initiates a cascade of hormonal changes in the body that can lead to the dangerous condition of diabetic ketoacidosis (DKA). If left untreated, it can lead to coma and death.
In the face of inadequate circulating insulin, glucose builds up in the blood instead of moving into the tissue cells where it would be used for fuel. Without glucose to burn for energy, the body turns to fat for fuel.
The special type of fat it uses is called ketones. Because ketones are an acid, the body needs to supply a base (the opposite of an acid) to neutralize their effects and maintain the blood’s natural pH. However, the body’s supply of base,such as NH3 (anydrous ammonia) (is limited and at some point the system is overwhelmed and the blood pH starts to decline. This drop in blood pH is one of reasons ketoacidosis is so serious. The body can’t accommodate changes in blood pH well.
Illness can often be a precipitating cause of DKA. Infection can spike glucose levels and additional insulin is often required. If the needs for additional insulin aren’t met, ketone production can start.
Ketoacidosis can also occur if children or teenagers omit insulin doses or continually under dose their insulin. Some children or teens use insulin omission as a method of weight control and should be warned about the dire consequences of this behavior.
Exercising with very high glucose levels , which usually reduces glucose concentrations, can also be a cause of DKA in the case of limited insulin supplies.
When to Check for Ketones
- Blood glucose is over 250 mg/dl for two tests in a row
- When your child is ill and blood glucose is over 250 mg/dl
- When your child plans to exercise and blood glucose is over 250 mg/dl
How to Check
There are two methods to check: blood and urine testing. In children, blood ketone checking is preferred. The precision Xtra® meter made by Abbott Diabetes Care and Nova Max Plus ®made by Nova Biomedical are the only meters currently available that provide blood ketone testing. The test is conducted using the same procedures as a blood glucose check and results are read in millimoles per liter (mmol/l).
- Below 0.6mm/l normal
- 0.6-1.5mmol/l- a problem may be starting that may require medical assistance
- Above 1.5 mmol/l – at risk for ketoacidosis Call your health care provider immediately
Urine ketone testing is a less exact method but supplies can be purchased at any pharmacy without a prescription. In urine ketone testing, a strip with a small pad is dipped into a minor quantity of urine and changes color. The color is matched to a key code on the strip vial. The darker the color the greater the amount of ketones present. Results are read as negative, trace, small, moderate or large amounts of ketones. Moderate and large amount of ketones require a call to your health care provider immediately.
The treatment for ketones in the presence of elevated blood glucose is additional insulin and fluids. It is good to have a sick day plan based on your current insulin regimen to instruct you how to calculate the additional insulin you need for ketones.
If ketones are present, in addition to calling your provider:
- Follow your child’s sick day plan. If you do not have one, call your health care provider and or educator to develop one
- Drink plenty of water and sugar-free fluids to dilute the blood of ketones and prevent dehydration
- Check for ketones every 3 to 4 hours if blood glucose remains over 250mg/dl.
- Do not exercise if blood glucose is over 250mg/dl and ketones are present
It is important to remember that ketones in the presence of high blood glucose are an emergency. There are other conditions that can produce ketones, however. In pregnancy, women can produce ketones in two situations: in the face of high blood glucose which requires the treatments described above) and also if the glucose level is normal. This type of ketones is called starvation ketones and the treatment is more carbohydrate not additional insulin. Some studies have suggested that this type of ketones affect the developing brain cells of the fetus and may lead to lower IQ levels.