How do you manage hyperkalemia?

Management of Hyperkalemia

The most effective approach to managing hyperkalemia includes immediate stabilization of cardiac membranes with intravenous calcium for severe cases with ECG changes, followed by shifting potassium intracellularly using insulin with glucose and inhaled beta-agonists, and ultimately removing excess potassium from the body using potassium binders or dialysis. 1, 2

Assessment and Classification

Severity Assessment

• Mild: 5.0-5.5 mmol/L with normal ECG
• Moderate: 5.6-6.5 mmol/L or with ECG changes
• Severe: >6.5 mmol/L or symptomatic or significant ECG changes

ECG Changes by Potassium Level

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

Treatment Algorithm

Step 1: Cardiac Membrane Stabilization (for severe hyperkalemia or ECG changes)

• Calcium gluconate: 10% solution, 15-30 mL IV
  • Onset: 1-3 minutes
  • Duration: 30-60 minutes
  • Note: Does not lower potassium levels but protects against cardiac arrhythmias 1, 2

Step 2: Intracellular Shift of Potassium

• Insulin with glucose:

  • 10 units regular insulin IV with 50 mL of 25% dextrose
  • Onset: 15-30 minutes
  • Duration: 1-2 hours 1, 2

• Inhaled beta-agonists (can be used concurrently):

  • 10-20 mg nebulized salbutamol over 15 minutes
  • Onset: 15-30 minutes
  • Duration: 2-4 hours
  • Evidence shows peak effect at 90-120 minutes with reduction of 1.18-1.29 mmol/L 1, 3

• Sodium bicarbonate (particularly if metabolic acidosis present):

  • 50 mEq IV over 5 minutes
  • Onset: 15-30 minutes
  • Duration: 1-2 hours
  • Less effective than insulin-dextrose or salbutamol 1, 3

Step 3: Potassium Removal from Body

• Potassium binders:

Characteristic	Sodium Polystyrene Sulfonate (SPS)	Patiromer	Sodium Zirconium Cyclosilicate (SZC)
Onset of action	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⁺)
Na⁺ content	1500mg per 15g dose	None	400mg per 5g dose
Serious AEs	Fatal GI injury reported	None reported	None reported

• Diuretics (if renal function adequate):

  • Loop diuretics (furosemide) to enhance potassium excretion
  • Combine with IV saline if patient can tolerate fluid load 2, 4

• Dialysis:

  • Consider for severe hyperkalemia unresponsive to medical therapy
  • Indicated in end-stage renal disease, severe renal impairment, or ongoing potassium release 2

Special Considerations

Medication Review

• Identify and discontinue medications that can cause or worsen hyperkalemia:
  • ACE inhibitors/ARBs/direct renin inhibitors
  • Potassium-sparing diuretics (spironolactone, eplerenone, amiloride, triamterene)
  • NSAIDs
  • Calcineurin inhibitors (cyclosporine, tacrolimus)
  • Beta-blockers (especially non-selective)
  • Trimethoprim
  • Heparin and derivatives 1, 5

Dietary Management

• Limit dietary potassium to <40 mg/kg/day
• Educate patients about high-potassium foods to avoid
• Teach techniques like pre-soaking root vegetables to reduce potassium content by 50-75% 1

Monitoring

• Check potassium and renal function within 1-2 days after initiating treatment
• Weekly monitoring for the first month, then monthly for 3 months
• Regular ECG monitoring to assess for hyperkalemia-related changes 1

Pitfalls and Caveats

1. Don't rely solely on potassium binders for acute, severe hyperkalemia due to their delayed onset of action 1

2. Watch for rebound hyperkalemia after temporary shifting treatments wear off, especially if the underlying cause isn't addressed 6, 2

3. Monitor for hypoglycemia when using insulin-dextrose therapy, particularly in patients with diabetes 2

4. Be cautious with sodium-containing treatments (sodium bicarbonate, SPS, SZC) in patients with heart failure or fluid overload 1, 2

5. Don't overlook transcellular shifts as a cause of hyperkalemia (acidosis, insulin deficiency, beta-blockers, digoxin toxicity) 6, 5

6. Check for hypomagnesemia when using patiromer, as it can bind magnesium 1

7. Consider the underlying cause of hyperkalemia to guide long-term management and prevent recurrence 2, 4