IV Potassium Push: Why Rapid Administration Causes Tissue Necrosis
Administering concentrated potassium chloride (KCl) as an IV push (bolus) is a **never event**. It causes extreme hyperkalemia locally and systemically, leading to cellular death, tissue necrosis, and fatal arrhythmias.
Mechanism of Injury
- Extravasation: High osmolarity (2000+ mOsm/L) and [K⁺] (20–40 mEq/10 mL) destroy endothelium and surrounding tissue.
- Direct cytotoxicity: High extracellular K⁺ depolarizes cells → sustained contraction, calcium influx, protease activation → necrosis.
- Vasoconstriction: High K⁺ → vascular smooth muscle contraction → ischemia.
Clinical Consequences
- Local: Pain, swelling, blistering, necrosis → compartment syndrome, phlebitis, thrombophlebitis, possible amputation.
- Systemic: Peak serum K⁺ → peaked T-waves, wide QRS, sine wave → VF/asystole within minutes.
Safe Administration Standards
| Parameter | Limit |
|---|---|
| Concentration | ≤ 40 mEq/L (peripheral); ≤ 80 mEq/L (central) |
| Rate (adult) | ≤ 10 mEq/hr (peripheral); ≤ 20 mEq/hr (central, monitored) |
| Rate (pediatric) | ≤ 0.5 mEq/kg/hr (max 10 mEq/hr) |
| Line | Central venous preferred; peripheral only if dilute + large vein + infusion pump |
| Monitoring | Continuous ECG, serial K⁺ q1–2h, urine output |