Contributor: Meghan Hurley, MD

Educational Pearls:

What is hyperkalemia?

Hyperkalemia is when the measured blood level of potassium reaches above 5.2 - 5.5 mEq/L (normal 3.5 - 5.2 mEq/L).

What are common causes of hyperkalemia?

What are concerns of hyperkalemia?

The biggest concern with hyperkalemia is the impact on the cardiac conduction system.

At differing levels of hyperkalemia, the patient may initially have peaked T waves, that then progress into a widening of the QRS complex which may eventually lead to a sine wave pattern.
This increases risk for cardiac arrest with ventricular fibrillation, PEA, and asystole.

What is the treatment algorithm for hyperkalemia?

Thought for the longest time to "stabilize the cardiac membrane/action potential". Recent research shows the true mechanism of action is likely through acting on calcium dependent channels.
Does not fix underlying hyperkalemia, but buys time for the heart.

Can be achieved through agents such as insulin (which may need to be bolused with glucose to prevent hypoglycemia), albuterol, or sodium bicarbonate.

If the patient is producing urine, loop or thiazide diuretics can be considered.
Hemodialysis may also be considered based on patient condition.
Long term (and slowest method of elimination) through fecal excretion. Unlikely to see benefits in emergency management.

Key Takeaways?

Hyperkalemia is a condition that can be brought on by primarily renal conditions and medication side effects. Careful attention must be paid to the patient's cardiac status, and urgent cardiac stabilization (though now we may know that calcium doesn't truly "stabilize" the cardiac membrane) must be performed to prevent deadly arrhythmias. Definitive management involves addressing the offending agent, offloading potassium, and stabilizing the patient long term.

References:

Geldermann N, Dzimiera J, Fischer H, Christ M. Acute hyperkalaemia in emergency care: evidence-based approaches. Emerg Med J. 2026;43(5):305-311. doi:10.1136/emermed-2025-215469
Piktel JS, Wan X, Kouk S, Laurita KR, Wilson LD. Beneficial Effect of Calcium Treatment for Hyperkalemia is Not Due to "Membrane Stabilization." Crit Care Med. 2024;52(10):1499-1508. doi:10.1097/CCM.0000000000006376
Hunter RW, Bailey MA. Hyperkalemia: pathophysiology, risk factors and consequences. Nephrol Dial Transplant. 2019;34(Suppl 3):iii2-iii11. doi:10.1093/ndt/gfz206

Summarized by Dan Orbidan, OMS3 | Edited by Dan Orbidan & Ahmed Abdel-Hafiz, NREMT-P