Significant hyperkalaemia is defined as a serum potassium value >6.0 mmol/L (>6.0 mEq/L). Moderate hyperkalaemia is defined as serum potassium values in the 5.0 to 6.0 mmol/L (5.0 to 6.0 mEq/L) range. Small changes in serum potassium values can have significant muscular and cardiac effects when significant hyperkalaemia is present.
Hyperkalaemia is most commonly due either to high intake of potassium in the setting of decreased renal excretion or to extracellular redistribution of potassium from intracellular locations. There is a limited correlation between an elevated serum potassium value and an excess in total body potassium stores. Clinical manifestations of hyperkalaemia are uncommon with values <6.0 mmol/L (<6.0 mEq/L).
Common acute manifestations of significant hyperkalaemia include muscle weakness and ECG changes, with the latter having the potential to progress to a life-threatening arrhythmia. Significant hyperkalaemia represents a medical emergency, and an ECG should be obtained to establish whether cardiotoxicity is present. Continuous ECG monitoring should occur until serum potassium values have been brought into a safe range and cardiotoxicity has resolved.
Whereas the treatment of significant hyperkalaemia is pre-emptive in the patient without electrocardiographic change, in the presence of electrocardiographic change significant hyperkalaemia represents a true medical emergency and requires rapid implementation of measures to reduce serum potassium concentration.
- Chronic kidney disease
- Diabetic ketoacidosis/hyperosmolar hyperglycaemic state
- Drug-related decreased cellular entry or increased cellular exit of potassium
- Potassium supplementation with underlying renal dysfunction
- Drug-related reduced urinary potassium excretion
- Acute kidney failure
- Renal tubular acidosis
- Metabolic acidosis
- Congenital adrenal hyperplasia
- Addison's disease
- Hyperkalaemic periodic paralysis
- Tumour lysis syndrome
Sri G. Yarlagadda, MD
The University of Kansas Medical Center
SGY declares that she has no competing interests.
Dr Sri G. Yarlagadda would like to gratefully acknowledge Dr Domenic Sica, a previous contributor to this topic. DS declares that he has no competing interests.
Manish Suneja, MD
Department of Internal Medicine
Division of Nephrology
University of Iowa Hospital and Clinics
MS declares that he has no competing interests.
Raj Thuraisingham, MBBS, MRCP, FRCP, MD
Royal London Hospital
RT declares that he has no competing interests.
- Guidelines for the treatment of hyperkalaemia in hospitalised adults
- European Resuscitation Council Guidelines for Resuscitation 2021: Section 6. Cardiac arrest in special circumstances
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