It is December 24 and I am "on call" for the Diabetes Program, sitting in my office at Children's National Medical Center. I am fielding phone calls from our patient population in District of Columbia, Maryland, Virginia, West Virginia, and parts of Pennsylvania.
‘Tis the season for viral respiratory infections, gastrointestinal viruses, pneumonias and...ketones. The development of ketones is a major concern and needs to be treated immediately as taught in the "survival skills" classes of all Diabetes Programs.
Why do ketones develop as a result of intercurrent illnesses?
Ketones result from the breakdown of fat when there is insufficient insulin to allow for transport of glucose into the cells for energy. Ketones result from fatty acid metabolism and decrease the blood pH. If the blood pH is less than 7.3, the diagnosis of Diabetic Ketoacidosis (DKA) is confirmed. People also may have "ketosis" if ketones are present without "ketoacidosis" if the pH is greater than 7.3. Depending on the situation, ketosis may often be treated (with medical consultation) at home.
- When a child/adolescent/adult is ill, there is increased metabolic stress with the release of counter-regulatory hormones (cortisol, glucagon, epinephrine, and nor-epinephrine) resulting in increased blood glucose concentrations to combat the "offending infectious organism." Blood sugars also may rise due to decreased activity.
- Ketones also may develop when caregivers inadvertently forego insulin injections due to decreased appetite and food intake; erroneously thinking that insulin is unnecessary since there is decreased carbohydrate consumption.
- Ketones also may develop with low or in-range blood sugars. The physiology is different in these situations where fat breakdown occurs because there is no glucose to metabolize! This situation typically occurs (under normal circumstances) upon awakening as no carbohydrates have been consumed overnight. With illness, oral input may be decreased resulting in what is called "starvation ketosis."
Treatment of ketones may be different depending on the severity or cause. Thus, in the presence of illness, it is important to check blood sugars frequently and monitor ketones via urine strips or serum testing (Precision extra meter and others).
<0.6 mm/L: normal (negative urine ketones)
0.6-1.5 mm/L: ketones beginning to develop-usually trace/small, as compared to urine
>1.5 mmol/L: moderate/large ketones, as compared to urine
At Children's National Medical Center, we provide the following recommendations for our children and families:
- During illness, check blood sugars more frequently and monitor for ketones. Even if blood sugars are in range, ketones must be checked.
- If ketones are less than moderate in association with elevated blood sugars, we suggest increasing fluid intake (without carbohydrates) such as water, crystal lite, diet soda etc.
- If ketones are moderate or large in association with elevated blood sugars, it is necessary to not only increase fluid intake, but provide extra insulin.
- For people employing split mixed insulin with NPH/Regular or rapid acting analog, we generally recommend giving 20 percent of the total daily dose of insulin along with increased fluids (8 ounces every hour if possible). For example: a 9-year old receives 14 NPH/6 regular at breakfast, 7 regular at dinner, and 7 NPH at bedtime. It is 3 pm and he has large ketones with a blood sugar of 400 mg/dl and is NOT vomiting. We suggest giving about 7 units of regular/rapid acting insulin at this time. As he is not vomiting, we ask him to drink 8 oz of water every hour and recheck blood sugar in 3-4 hours. At dinner if he still had moderate or large ketones with an elevated blood sugar, we would add an additional 7 units to his usual dinner 7 units of regular/rapid acting insulin.
- For people on multiple daily injections with basal insulin of Lantus or Levemir, we recommend calculating the correction bolus and adding an additional 20 percent of the rapid acting insulin. For example: blood sugar is 360 mg/dl, correction (insulin sensitivity factor) is 30 and target is 120 mg/dl. Correction bolus is: 360 -120/30= 8 units. 8 units plus 20 percent extra = 9.6 (10 units). Consuming 8 oz of non-carbohydrate containing fluids every hour also would be required if not vomiting.
- For people on the insulin pump, if ketones are present we recommend the same calculation as above for MDI. However, we strongly advise that the insulin be administered by injection rather than by the pump. We suggest that one make certain the infusion set is intact as well as ensuring that the pump is functioning appropriately. Fluids should be administered as above.
- For people with low or blood sugars in range with moderate or large ketones, the first step is to provide fluids with glucose and determine if the ketones resolve. Sometimes, to eliminate ketones, we need to increase the blood sugar to enable insulin administration.
- We strongly advise close contact with your primary care provider to manage your intercurrent illness in terms of the need for additional medications or treatment. Once the primary care provider has diagnosed the illness, your diabetes team will support your blood sugar management. Keep in mind that if vomiting occurs with the association of ketones, we will ask you to go to your nearest Emergency Department to receive IV fluids to prevent or treat dehydration and provide medication to stop vomiting. It is important, however, that your child be examined to rule out any underlying abdominal problems (such as appendicitis etc.) before anti-emetic medication is prescribed.
Please keep this information handy during this winter season to get a "head start" in avoiding an unwanted trip to your local Emergency Department!