Post-Dialysis Management of Hyperkalemia
After a patient receives dialysis for hyperkalemia, the next step is to implement measures that prevent recurrence while addressing the underlying cause, including dietary potassium restriction, medication review with discontinuation of potassium-elevating drugs, and initiation of newer potassium binders (patiromer or sodium zirconium cyclosilicate) to maintain normokalemia between dialysis sessions. 1, 2
Immediate Post-Dialysis Assessment
Monitor serum potassium levels within 2-4 hours after dialysis completion to confirm adequate reduction and establish a baseline for ongoing management, as potassium can rebound after dialysis due to transcellular shifts. 1, 3 Verify that ECG changes have resolved if they were present initially, as peaked T waves, widened QRS, or prolonged PR intervals indicate cardiac membrane instability requiring urgent intervention. 1, 4
Prevention of Recurrent Hyperkalemia
Dietary Management
Implement strict dietary potassium restriction, limiting intake to 2,000-3,000 mg daily by avoiding high-potassium foods (bananas, oranges, potatoes, tomatoes, processed foods) and potassium-containing salt substitutes. 1, 2 However, recognize that overly restrictive diets can compromise nutritional status in dialysis patients, making newer potassium binders particularly valuable. 2
Medication Review and Adjustment
Discontinue or reduce medications that promote hyperkalemia, including:
- NSAIDs, which impair renal potassium excretion 1
- Potassium supplements and potassium-sparing diuretics 1
- Trimethoprim, heparin, and beta-blockers 1
For patients requiring RAAS inhibitors (ACE inhibitors, ARBs, mineralocorticoid antagonists) for cardiovascular or renal protection, do not permanently discontinue these life-saving medications. 1 Instead, temporarily reduce or hold them if potassium exceeded 6.5 mEq/L, then restart at lower doses once potassium normalizes, using concurrent potassium binder therapy to maintain normokalemia. 1
Initiation of Potassium Binder Therapy
Newer potassium binders are strongly preferred over sodium polystyrene sulfonate (SPS/Kayexalate), which has limited efficacy data and serious gastrointestinal adverse effects including bowel necrosis. 1, 2
Sodium Zirconium Cyclosilicate (SZC/Lokelma)
For hemodialysis patients, administer SZC only on non-dialysis days at a starting dose of 5 g once daily, or 10 g once daily if potassium was greater than 6.5 mEq/L. 5 SZC has rapid onset of action (approximately 1 hour) and effectively maintains normokalemia between dialysis sessions. 6, 1 Monitor pre-dialysis potassium after the long interdialytic interval and adjust dosing in 5 g increments weekly, with a maintenance range of 5-15 g once daily on non-dialysis days. 5
Patiromer (Veltassa)
Alternatively, use patiromer 8.4 g once daily with food, titrated up to 25.2 g daily based on potassium levels. 1 Patiromer has slower onset (approximately 7 hours) but provides sustained potassium control. 6, 1 Separate administration from other oral medications by at least 3 hours due to binding interactions. 6, 1
Monitoring Protocol
Check serum potassium within 1 week after initiating potassium binder therapy, then weekly during dose titration. 1 Once stable, monitor pre-dialysis potassium levels before each dialysis session, as patients on hemodialysis remain at high risk for recurrent hyperkalemia, particularly after the long interdialytic interval. 2, 7
Monitor for hypokalemia, which can be equally dangerous, especially in patients prone to acute illnesses causing decreased oral intake or diarrhea. 5 Adjust or discontinue the potassium binder if potassium falls below the desired target range (typically 4.0-5.0 mEq/L). 1, 5
Special Considerations for Dialysis Patients
Avoid prolonged fasting between dialysis sessions, as catabolism can provoke hyperkalemia by releasing intracellular potassium. 7 If fasting is necessary, consider intravenous dextrose administration to prevent hyperkalemia. 7
Recognize that dialysis is the definitive treatment for severe hyperkalemia in ESRD patients, removing potassium rapidly and reliably. 7, 3 However, between-session management with dietary restriction and potassium binders is essential to prevent life-threatening recurrence. 2, 7
Common Pitfalls to Avoid
Do not rely solely on dietary restriction, as compliance is difficult and nutritional compromise is common in dialysis patients. 2 Potassium binders enable less restrictive diets while maintaining normokalemia. 2
Do not permanently discontinue RAAS inhibitors in patients with cardiovascular disease or proteinuric kidney disease, as these medications provide mortality benefit and slow disease progression. 1 Use potassium binders to enable continuation of these life-saving therapies. 1
Do not use sodium polystyrene sulfonate (Kayexalate) for chronic management due to risk of bowel necrosis and limited efficacy. 1, 2 Newer agents (patiromer, SZC) are safer and more effective. 1, 2
Monitor for edema with SZC, as each 5 g dose contains approximately 400 mg sodium. 5 Adjust dietary sodium and increase diuretics as needed, particularly in patients with heart failure or fluid overload. 5