Advanced Practice: Electrolyte Management in DKA!



  • Most DKA patients are whole body depleted on presentation: average 3 to 5 mEq/kg total body potassium deficit

  • During initiation of treatment with insulin the serum potassium concentration can rapidly drop resulting in life threatening cardiac arrhythmias

  • Initial hypokalemia ( <3.3 mEq/L ) needs aggressive potassium replacement before insulin therapy is started - treatment with IV potassium until K >3.5 mEq/L

  • Initial potassium level >3.3 mEq/L and <5.2 mEq/L needs concurrent potassium replacement with insulin therapy - treatment with IV potassium for at least 4 hrs

  • Initial hyperkalemia ( >5.2 mEq/L ) needs fluid replacement and insulin therapy which will often lower the potassium level rapidly


  • Osmotic diuresis may cause hypomagnesemia

  • If serum magnesium concentration is <2.0 mEq/L or symptoms are present consistent with hypomagnesemia - treat with IV magnesium sulfate 2-4 g IV


  • Initially serum phosphate levels are often normal or increased, phosphate then reenters intracellular space during insulin therapy causing hypophosphatemia (most severe 1 to 2 days after initiation of insulin therapy)

  • No role for starting phosphate replacemnt in ED for DKA patients unless phosphate concentration <1.0 milligram/dL





Tintinalli, JE. Tintinalli's Emergency Medicine: A Comprehensive Study Guide. 8th ed. New York, NY: McGraw-Hill Education LLC, 2016.