Management of Hyperkalaemia (plasma K+ >5.5mmol/L)

In a cardiac arrest follow separate flowchart ‘Hyperkalaemia Management in Cardiac Arrest’ which can be found on the emergency drug trolley.

Assessment / monitoring

  • Assess clinical status of the patient
  • Perform immediate 12-lead ECG on the patient if K+ ≥6mmol/L:
    • If ECG changes - seek senior help and follow the flowchart below for immediate management.
    • If no ECG change, exclude spurious hyperkalaemia and repeat blood sample.

General management

  • Check for ECG changes and initiate emergency management as appropriate.
  • N.B. Use caution acting on a potassium result from an arterial blood gas (ABG) until confirmed by a laboratory sample, unless in an emergency.
  • If patient is on long-term dialysis - contact the on-call renal consultant immediately.
  • Identify and treat underlying cause(s) where possible:
    • Potassium supplements, ACE inhibitors, angiotensin receptor blockers, potassium-sparing diuretics (e.g. spironolactone, eplerenone), co-trimoxazole and trimethoprim should be withheld / discontinued and, if appropriate, review re-initiating once clinically stable.
    • Renal failure – seek advice from on-call renal consultant where required.
    • Hypovolaemia – consider volume expansion with IV sodium chloride 0.9%.
    • Severe acidosis (often associated with renal failure) – consider IV sodium bicarbonate 1.26% 500ml over 1 hour (seek senior medical advice).
    • Hypoaldosteronism, e.g. insufficient steroid dosing or Addison's disease – seek advice from endocrinologist where required.
    • Poorly controlled glycaemia in insulin dependent diabetes.
  • If hyperkalaemia remains unexplained, more specialised investigation may be appropriate. Seek advice from a Consultant Biochemist where required.

Drug therapy / treatment options

See the flowchart for the management of mild, moderate and severe hyperkalaemia. Below are additional notes to accompany the guidance in the flowchart.

Additional notes to accompany the flowchart:

Mild hyperkalaemia – confirmed plasma K+ 5.5–5.9mmol/L:

  • Consider causes and need for treatment - often withholding contributing medicines or dietary changes are sufficient.
  • Monitor K+ levels closely.

Moderate hyperkalaemia – confirmed plasma K+ 6–6.4mmol/L:

  • Perform immediate 12-lead ECG:
    • If ECG changes present, treat as severe hyperkalaemia.
    • If no ECG changes present, commence IV insulin-glucose infusion in addition to nebulised salbutamol to reduce plasma potassium.

Severe hyperkalaemia – confirmed plasma K+ ≥6.5mmol/L and/or ECG changes (although treatment should not be delayed, result should be confirmed):

  • Seek senior support
  • Ensure continuous cardiac monitoring
  • If K+ >6.5mmol/L despite treatment options outlined in the flowchart, contact oncall renal consultant as patient may require dialysis.
  • Check plasma K+ at 1 hour, 4 hours, 6 hours and 24 hours after treatment.
  • Check capillary blood glucose (CBG) before starting insulin-glucose infusion, following the infusion and then at 30mins, 60mins, 90mins, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 8 hours and 12 hours post-infusion.

Further notes

  • Note: calcium resonium is no longer routinely recommended in the treatment of acute hyperkalaemia.
  • A repeated dose of insulin-glucose infusion may be necessary for severe hyperkalaemia (K+ ≥6.5mmol/L) if refractory to initial therapy or if rebound occurs.
  • Hyperosmolar glucose infusions should not be used in diabetic ketoacidosis.

 

Guideline reviewed August 2024
Page updated December 2024



;