Hypokalemia — Replacement & Nursing

Potassium replacement depends on severity. Mild hypokalemia (3.0–3.4 mEq/L) in a stable client is corrected with oral supplements — potassium chloride (KCl) 20–40 mEq PO given with a full glass of water and food to prevent GI irritation. Never crush extended-release tablets. For moderate to severe hypokalemia (< 3.0 mEq/L) or when the client cannot take PO, IV replacement is used. The critical safety parameters for IV potassium: never exceed 10 mEq/hour via peripheral line (up to 20 mEq/hour via central line with continuous cardiac monitoring), never give IV push or bolus, and the maximum concentration for peripheral infusion is 40 mEq/L. Higher concentrations require central access. Always use an infusion pump — gravity drip is never acceptable. During IV infusion, place the client on continuous cardiac monitoring and assess the IV site frequently because KCl is a vesicant that causes phlebitis and tissue necrosis if it infiltrates. Before administering potassium, verify adequate urine output (≥ 0.5 mL/kg/hr) — impaired renal excretion increases hyperkalemia risk. Recheck the potassium level after replacement. Concurrently assess magnesium — hypomagnesemia makes hypokalemia refractory to correction, so magnesium must be repleted first or simultaneously.