Diabetic KetoALKALOSIS

A Case:

• A man presents to the ED with T1DM. He has had 2 days of nausea, vomiting, and abdominal pain. Looks ill. You get labs. You have a BG of 280, a pH of 7.47, and a HCO3 of 19. Is this DKA?

• You look a smidge closer. You see an Anion Gap of 29. Is this DKA?

• Your BHB comes back and it's >6 mmol/L. Lactate is 3.  Is this DKA?

Very nerdy/academic question from this past string of shifts….

What in the world is Diabetic Keto-ALKALOSIS??

Source: https://www.sciencedirect.com/science/article/abs/pii/S073646792200806X?via%3Dihub

• Turns out, you don't need the "A" in DKA, and you don't really need the "D" (eg. Euglycemic DKA).  All you really need is the ketosis (which is not the same as low bicarb) that you can ascribe to ineffective insulin action.

• Key-Pearls

  • When we think about DKA, we typically consider the traditional criteria that include a BG >250 mg/dL, presence of serum or urine ketones, and acidosis defined by a pH <7.3, a HCO3 <18 mmol/L, or anion gap >10-12 mmol/L

  • However...people with DKA often have mixed acid-base disorders, including volume contraction (from massive diuresis) or emesis-driven primary metabolic alkalosis or Kussmaul breathing driven primary respiratory alkalosis.

  • So...patients with diabetes can present with positive serum ketones, an elevated AG, BUT with pH > 7.3 or a bicarbonate >18 mmol/L. Some can even present with an alkalosis/alkalemia.

  • This is much more common than we think. In the above study, of 259 consecutive encounters for diabetes, for patients with positive serum BHB and an elevated AG, only 63% of cases were captured by traditional DKA criteria. Don't be fooled by the pH!

  • Remember. Acidosis refers to a physiologic process while acidemia refers to blood pH. We are treating a diabetic ketoacidosis...NOT diabetic ketoacidemia.

  • An elevated AG in combination with an elevated BHB may be a more sensitive parameter to identifying "DKA". 

  • Diabetic ketoalkalosis warrants the same prompt treatment protocol as traditional DKA. Severe ketoacidosis and a severe AGMA in the setting of DM warrants ICU admission even if the pH isn't "acidemic". 

See you next shift,

Dillon