Diabetic Ketoacidosis

Diabetic ketoacidosis is a severe and potential life-threatening complication of diabetic mellitus. Glucose levels are usually moderately elevated, however they can range from normal/slightly increased levels (euglycemic states) to high levels exceeding 900 mg/dl in comatose patients. The treatment relies on fluid & electrolyte replacement, insulin administration and glucose administration.

Guidelines of from different regions have variations in therapy, for instance the ADA suggests half-isotonic (0.45 %) saline in the fluid replacement regime, the Joint British Diabetes Society and the German guideline recommend 0.9 % in almost all cases. In the European pediatric guidelines, the use of “a solution with a tonicity ≥0.45 %” is recommended, stating that 0.9 % or 0.45 % with added potassium can be used. Due to the various recommendations, the reader is advised to also consult local hospital guidelines on fluid therapy.

Diagnosis

• D: elevated blood glucose levels or known diabetes mellitus
• K: elevated blood ketone concentration or significant ketonuria
• A: low bicarbonate (< 15 mmol/l) and/or pH < 7.3

When treated with SGLT2 inhibitors, the resulting glucosuria can minimize the developing hyperglycemia.

DKA can develop due to insulin deficiency. In non insulin-dependent patients however (i.e. d.m. type 2 with remaining insulin production) the DKA has often an underlying cause that needs to be identified, including infection, trauma, mediation, etc.

Management

• regular monitoring of blood pressure, heart rate, GCS
• regular monitoring of glucose, venous or arterial BG (pH, bicarbonate, base excess, anion gap), Na, K
• central line if needed, peripheral lines might have a larger diameter depending on available equipment
• urinary catheter for measuring urinary output reliably

Fluids and Electrolytes

• first hour:
  • in hypovolemic shock: isotonic saline or balanced crystalloid as fast as possible (e.g. 500 ml/10 min), involve critical care
  • in hypovolemia (RR > 90 mmHg): 1,000 ml/60min of isotonic saline or balanced crystalloid
  • in euvolemia: guide volume by clinical assessment
• after second or third hour:
  • further infusion with 200 to 500 ml/h depending on hemodynamics
    • Success criteria: improved blood pressure, improved urinary output
• Potassium:
  • < 3.3 mmol/l: don’t give insulin, correct potassium, e.g. with 20 to 40 mEq/l of fluid
  • 3.3 – 5.3 mmol/l: add 20 to 40 mEq to each liter, aim for 4–5 mmol/l
  • 5.3 mmol/l: delay potassium until values fall below this level

Insulin and Glucose

• Patients with existing insulin medication:
  • Insulin pumps should be stopped and removed, it might not work correctly
  • Long acting insulin (glargine, detemir, deglutec) should continue at usual dose and time
• Insulin infusion
  • If patient is not hypokalemic, start insulin immediately
  • initial bolus is generally not recommended, can be considered if patient severly acidotic or continuous infusion not immediately available
    • 10 units i.v.
• fixed rate intravenous insulin infusion
  • start with 0.1 U/kg/h (max. 15 U/kg/h)
  • Stay on target:
    • decrease glucose by 50 mg/dl/hour
    • increase bicarbonate by 3 mmol/l/hr
    • decrease blood ketones by 0.5 mmol/l/hr
    • potassium between 4.0 and 5.5 mmol/l
  • if correction too slow: increase rate by 1 U/h
    • check connections to be sure, that insulin is delivered. Remove IV filters that may bind insulin.
    • UpToDate states a doubling of infusion rate can be used
  • when glucose falls to 200 – 300 mg/dl consider reducing rate to 0.02 to 0.05 units/kg/h
    • glucose should not fall below 200 mg/dl
• intravenous glucose
  • once serum glucose is 200 – 300 mg/dl i.v dextrose is needed as additional substrate
    • consider cutting fluid rate in half and add the same amount of dextrose (e.g. 200 ml/h saline ⇾ 100 ml/h saline + 100 ml/h dextrose 10%)
• continue insulin and i.v dextrose until patient is eating and drinking normally
  • patient should have received long acting insulin 1 to 2 hours before stopping
• if patient has newly diagnosed diabetes
  • start long acting insulin with 0.25 U/kg s.c. daily

Additional links

• DKA in the Internet Book of Critical Care
• DKA on Life in the Fast Lane
• UpToDate Article on the management of DKA
• ADA Guideline
• Canadian Guidelines
• JBDS Guidelines (UK), has management charts at the end of the file
• European pediatric guidelines

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