In DKA, if serum potassium is less than 3.3 mEq/L, which action should be taken?

• A. Start insulin and hold potassium
• B. Do not administer potassium yet
• C. Administer potassium before insulin
• D. Administer calcium first

Answer: (C)

Potassium management drives the safety of treating in DKA. In this state, total body potassium is usually depleted, even if the serum value isn’t high, and insulin therapy will push potassium into cells. If the serum potassium is very low (less than 3.3), starting insulin without first correcting potassium can cause a rapid, dangerous drop in serum K+, leading to life-threatening hypokalemia and arrhythmias. Therefore, the priority is to administer potassium now to raise serum K+ to at least 3.3 mEq/L, then begin insulin therapy while continuing potassium replacement to keep K+ in the roughly 4–5 mEq/L range. This approach prevents the insulin-induced K+ shift from causing severe hypokalemia and stabilizes the patient as the acidosis resolves.