Treatment of Hyperkalemia
The treatment of hyperkalemia requires a stepwise approach starting with calcium gluconate for cardiac membrane stabilization, followed by insulin with glucose for intracellular potassium shifting, and ultimately removal of excess potassium from the body through dialysis or newer potassium binders. 1
Emergency Management of Severe Hyperkalemia (>6.5 mmol/L or with ECG changes)
Cardiac Membrane Stabilization (immediate effect)
- Administer IV calcium gluconate 10% solution (15-30 mL)
- Onset: 1-3 minutes
- Duration: 30-60 minutes
- Note: Use calcium chloride instead if patient is in cardiac arrest 2
Intracellular Potassium Shifting (15-30 minute onset)
- Administer 10 units regular insulin IV with 50 mL of 25% dextrose
- Consider adding inhaled beta-agonists (10-20 mg nebulized over 15 minutes) as adjunctive therapy
- Consider sodium bicarbonate (50 mEq IV over 5 minutes) if concomitant metabolic acidosis present
- Monitor glucose levels to prevent hypoglycemia
Potassium Removal from Body
- Hemodialysis: Most rapid and effective method for eliminating potassium 1
- Loop diuretics: Promote renal potassium excretion in patients with adequate renal function
ECG Changes in Hyperkalemia
| Potassium Level | ECG Changes |
|---|---|
| 5.5-6.5 mmol/L | Peaked/tented T waves (early sign) |
| 6.5-7.5 mmol/L | Prolonged PR interval, flattened P waves |
| 7.0-8.0 mmol/L | Widened QRS, deep S waves |
| >10 mmol/L | Sinusoidal pattern, VF, asystole, or PEA |
Non-Emergency Management of Mild to Moderate Hyperkalemia
Newer Potassium Binders (preferred for chronic management)
- Sodium zirconium cyclosilicate (SZC): Onset 1 hour, highly selective
- Patiromer: Onset 7 hours, moderately selective
- Both have better safety profiles than traditional sodium polystyrene sulfonate 1
Traditional Potassium Binders
Comparison of Potassium Binders
| Characteristic | SPS | Patiromer | SZC |
|---|---|---|---|
| Onset of action | Variable; several hours | 7 hours | 1 hour |
| Site of action | Colon | Colon | Small and large intestines |
| Selectivity | Low (binds Ca²⁺, Mg²⁺) | Moderate (binds Na⁺, Mg²⁺) | High (mainly binds NH₄⁺) |
| Serious AEs | Fatal GI injury reported | None reported | None reported |
Additional Management Considerations
Eliminate reversible causes:
- Review and adjust medications that can cause hyperkalemia (ACE inhibitors, ARBs, potassium-sparing diuretics)
- Correct metabolic acidosis if present
- Avoid potassium-containing IV fluids (e.g., Lactated Ringer's solution) 1
Patient education:
- Counsel patients to avoid high-potassium foods
- Advise against NSAID use which can worsen hyperkalemia
- Maintain adequate hydration
- Implement sodium restriction (<2g/day) and regular physical activity 1
Important Caveats
- ECG manifestations of hyperkalemia vary between individuals and may not always follow a predictable pattern. Some patients show minimal ECG changes despite dangerously high potassium levels 1
- Sodium polystyrene sulfonate should not be used for emergency treatment of life-threatening hyperkalemia due to its delayed onset of action 3
- Hemodialysis remains the most reliable method to remove potassium from the body and should be used in cases refractory to medical treatment 4
- Monitor for rebound hyperkalemia after temporary shifting treatments wear off, particularly in patients with ongoing causes of potassium elevation 5