January 8, 2008
Hyperglycemia and DKA
Question from Longview, Texas, USA:
My daughter was recently hospitalized with DKA. This was the first time since her diagnosis almost eight and a half years ago. I'm not sure how high her blood sugar actually got because I'd already given her insulin with a syringe before I took her to the hospital. However, when she was admitted, her CO2 was 9.2, BUN 20, Creat. 1.1, sodium 134, potassium 5.1, chloride 99, SGOT 48, total protein 9.1, anion gap 25.4, calcium 10.2. Her blood acetone level was "large." Her urinalysis showed specific gravity - 1.011, PH (urine) 5.0, protein 30, glucose over 1000, ketone over 80, blood trace. Which of these laboratory results are used to determine DKA? And, more importantly, how SEVERE was the DKA? Is the diagnosis made from the blood sugar level, acetone, CO2, and ketones? I am trying to make sense of all the laboratory values but I need some help. I know that all DKA is dangerous, but was this a mild case or severe? Does the severity of the DKA depend on how long they are in it?
The glucose level, the presence of ketones, and the degree of acid accumulation all contribute to DiabeticKetoAcidosis (DKA). Acid or even acid with ketones do not qualify for DKA if the glucose is not elevated.
The severity of DKA, in my mind, hinges on the degree of acidosis and the duration of time that has led to the concurrent dehydration, ketone production, the electrolyte disturbances, and the acids. The degree of elevated blood glucose is arguably the least important.
So, your child’s serum electrolytes are interesting. This is not the forum for a physiology lecture, but the serum C02 of 9 suggests a near- severe acidosis: the normal value is around 25 or so. Serum C02 reflects the buffering agent in blood called “bicarbonate” (previous generations took “a bicarb” when they had heart burn to sooth stomach acid; Tums and Rolaids are bicarbonates – but don’t take them to cure DKA! INSULIN is required to treat DKA.) We “use up” our own blood bicarbonate as our bodies’ try to buffer the increasing acids. So, a C02 of 9 says that we’ve used up most of the buffering and acids are still in high concentration. The “anion gap” is a reflection of electronic neutrality: The positively charge particles (“cations” – pronounced “CAT- eye-uns”) pretty much should be offset with the negatively charged particles, called anions (ANN-eye-uns). The normal anion gap is about 6 to 12 and is typically calculated as the difference in the sodium value minus the chloride minus the C02 value. A large anion gap implies lots of acids because of too little C02.
Ketones in the blood or urine are commonly graded as none-trace-small-moderate-large. The normal situation should be no ketones. DKA does not happen over a rapid period of time. It typically takes hours to days to develop DKA; it typically takes hours to days to reverse. Your daughter’s values strongly suggest that she was without adequate insulin for a significant period of time.
The vomiting and dehydration of DKA often heralds the breakpoint of getting seriously ill with DKA. To this end, many endocrinologists inform their patients to check for ketones in blood or urine (with appropriate test strips) when the serum glucose is over 240 mg/dl [13.3 mmol/L] to 300 mg/dl [16.7 mmol/L] and with illnesses, especially with vomiting, regardless of the glucose. (Eating bad tuna salad may make you vomit. Ketones make you vomit. How do you know what caused the vomiting in a patient with diabetes? Check for ketones. Eating bad tuna salad would not be expected to be associated with moderate-large ketones.)
DKA can be fatal. It is always serious, even if the acids are only “moderate.” Trace to small ketones usually are not as worrisome.
Talk with your child’s Certified Diabetes Educator or pediatric endocrinologist for more information. Knowledge is power!