What is acute hyperkalemia?

Acute hyperkalemia is caused mainly by abnormal release of potassium from cells (often due to trauma) and is the result of a single event with a clear etiology that does not require ongoing management.1

One of the challenges of treating hyperkalemia is that it is often asymptomatic and therefore may go unnoticed until it reaches unsafe levels. Often it is discovered during routine laboratory tests.2,3 The clinical consequences of hyperkalemia are recognized as requiring immediate attention. Serum potassium levels exceeding 6.5 mEq/L can lead to cardiac arrhythmias and other serious risks.2,3

Common clinical manifestations of hyperkalemia


  • Electrocardiogram (ECG) changes, including peaked T-waves, PR-interval prolongation, and QRS widening
  • Arrhythmias (eg, bradyarrhythmias, ventricular fibrillation, and asystole)


  • Muscle twitching or cramping
  • General weakness
  • Paralysis
  • Diarrhea
  • Abdominal pain
  • Myalgia
  • Flaccid paralysis of the extremities

Electrocardiogram as a guide for hyperkalemia severity

ECG findings are frequently used to gauge the severity or potential medical impact of elevated serum K+.5,6 However, the ECG is not always a reliable indicator of the potential consequences of the hyperkalemia at hand. In a retrospective view of 90 patients with hyperkalemia, 80% of whom had serum K+ >7.0 mEq/L, ECG findings were relatively normal and did not lead to proper management of hyperkalemia. In cases where elevated serum K+ is not associated with heart arrhythmias, relying on the ECG may provide a false sense of security.5

This chart features a decision-tree for evaluating hyperkalemia. Approachesto evaluation include limiting dietary intake of potassium and withdrawing or titrating medications associated with hyperkalemia.