Diabetic Ketoacidosis

Criteria:

  • Elevated glucose

  • Acidosis

  • Decreased bicarb

  • Elevated anion gap

  • Elevated ketones

Patients present with elevated glucose on triage. The majority of the time this will just be

hyperglycemia, but DKA/HHS must be ruled-out.

  • Order BMP, mag, phos, vbg, ketones (beta-hydroxybutyrate), and osmolality.

  • Start fluids, 2L of either LR or NS is a good choice, cheaper than plasmalyte and likely will not need more if the patient is not in DKA/HHS.

High glucose, low bicarb, elevated anion gap, acidosis, elevated ketones, and variable mental status point toward a diagnosis of DKA. High glucose, normal bicarb, normal pH, normal ketones, elevated serum osmolality, and stupor/coma point towards HHS.

Placing patients on end tidal capnography may be useful as well. End tidal capnography greater than or equal to 35 is 100% sensitive in ruling out DKA and end tidal capnography less than or equal to 21 is 100% specific to rule in DKA.

At this point continue LR or switch to plasmalyte. Patients in DKA can be in ~6L of fluid deficit. Make sure the patient has 3 good IV lines. Can switch fluids to infusion rate after first hour. The mainstay of treatment for HHS will also be continued fluid repletion.

The next step is to evaluate the potassium level. 

  • <3.5: Do not start insulin. Give potassium supplementation. 10 mEq will raise potassium level by ~0.1. Can do 10 mEq/hr per peripheral IV line, or 20 mEq/hr from central line. Can also give 40 mEq orally per hour if patient can tolerate it. 

  • 3.5-5.5: Start insulin. Start drip at 0.1 u/kg/hr. Give potassium supplementation of 20-30 mEq/hr. 

  • >5.5: Start insulin drip at 0.1 u/kg/hr. 

Additional Steps

  • Replete mag and phos as necessary. 

  • Check finger sticks hourly. Repeat chemistry every 2 hours. 

  • Once FS or glucose drops <250, start D5. Can do this by using D5-LR, D5-1/2NS, or two bag technique (can google it). Keep goal glucose between 150-200.  Run potassium with the fluids as mentioned above. 

  • Admit patient to ICU or floors as per institution guidelines.

Akash Shah, PGY4

Source: https://wikem.org/wiki/Diabetic_ketoacidosis