Management of Hyperkalemia in an Elderly Patient with Multiple Comorbidities
Immediate Priority: Address the Hyperkalemia (K+ 6.3 mEq/L)
Hold the ACE inhibitor (lisinopril) immediately and initiate sodium zirconium cyclosilicate (SZC/Lokelma) 10g three times daily for 48 hours, then transition to 10g once daily for maintenance while monitoring for rebound hyperkalemia. 1, 2
Acute Management Protocol
Obtain an ECG immediately to assess for peaked T waves, flattened P waves, prolonged PR interval, or widened QRS complexes, which would indicate urgent need for IV calcium gluconate regardless of the exact potassium value. 1, 3 Even though the patient denies cardiac symptoms, ECG changes can be present without symptoms and indicate life-threatening risk. 1
If ECG changes are present: Administer IV calcium gluconate 15-30 mL of 10% solution over 2-5 minutes to stabilize the cardiac membrane (onset 1-3 minutes, duration 30-60 minutes). 1, 3 This does NOT lower potassium—it only temporizes. 1
For potassium redistribution (if needed urgently): Consider insulin 10 units IV with 25g dextrose (onset 15-30 minutes, duration 4-6 hours) and/or nebulized albuterol 10-20 mg (onset 30 minutes, duration 2-4 hours). 1, 3 However, given the patient's K+ of 6.3 without ECG changes, these may not be immediately necessary if SZC is initiated promptly. 1
Do NOT use sodium bicarbonate unless metabolic acidosis is documented (pH <7.35, bicarbonate <22 mEq/L), as it is ineffective without acidosis and wastes time. 1, 3
Potassium Elimination Strategy
Initiate sodium zirconium cyclosilicate (SZC/Lokelma) 10g orally three times daily with meals for 48 hours, then 10g once daily for maintenance. 1, 2 SZC has a rapid onset of action (~1 hour) and is highly effective in this clinical scenario. 1, 2 The FDA label confirms this dosing for initial treatment of hyperkalemia. 2
Separate SZC from other oral medications by at least 2 hours before or after administration to avoid drug interactions. 2
Monitor serum potassium within 48 hours after initiating SZC, then weekly during dose titration, then at 1-2 weeks, 3 months, and every 6 months thereafter. 1, 3
Adjust SZC dose based on potassium levels: Maintenance dose range is 5g every other day to 15g daily. 2 Decrease or discontinue if potassium falls below 4.0 mEq/L. 1, 2
ACE Inhibitor Management
Temporarily hold lisinopril until potassium is <5.0 mEq/L, then restart at a lower dose (e.g., 5mg daily instead of 20mg) with concurrent SZC therapy. 1, 3 Do NOT permanently discontinue the ACE inhibitor, as this leads to worse cardiovascular and renal outcomes in patients with CKD, hypertension, and history of stroke. 4, 1
The combination of CKD stage 2 (eGFR 63) and ACE inhibitor use is the primary driver of this patient's hyperkalemia. 1, 5
SGLT2 inhibitors reduce hyperkalemia risk and should be considered as an adjunct therapy to allow continuation of RAAS inhibition. 4, 1 This patient would benefit from adding an SGLT2 inhibitor (e.g., empagliflozin or dapagliflozin) for both cardiovascular and renal protection while helping maintain normokalemia. 4
Dietary Potassium Restriction
Reinforce dietary potassium restriction, but focus on reducing nonplant sources and processed foods rather than eliminating all high-potassium foods. 1, 6 The evidence supporting strict dietary restriction is limited, and potassium-rich fruits and vegetables provide cardiovascular benefits. 1
Avoid: Bananas, oranges, potatoes, tomatoes, salt substitutes (which contain potassium chloride). 1
Limit processed foods with phosphate additives, as these contain hidden potassium. 7
Consider referral to renal dietitian for individualized dietary counseling that balances adequate protein intake (important for this patient with low total protein 5.9 g/dL) with potassium restriction. 1, 6
Secondary Priority: Manage Anemia and Protein-Calorie Malnutrition
Anemia Management (Hgb 10.8 g/dL)
Check iron studies (serum iron, TIBC, ferritin, transferrin saturation) and consider iron supplementation if deficiency is present. 7 This patient's anemia is likely multifactorial: CKD stage 2, recent sepsis/pneumonia, and protein-calorie malnutrition. 7
If functional iron deficiency is present (low transferrin saturation despite normal/high ferritin), consider intravenous iron supplementation, which is more effective than oral iron in CKD patients. 7
Erythropoietin-stimulating agents (ESAs) are NOT indicated at this hemoglobin level (10.8 g/dL) unless iron deficiency is corrected first and hemoglobin remains <10 g/dL. 7
Protein-Calorie Malnutrition Management
Continue nutritional supplementation and dietitian follow-up, targeting total protein >6.5 g/dL and albumin >3.5 g/dL. 1 The patient's low total protein (5.9 g/dL) and borderline prealbumin (22 mg/dL) indicate ongoing malnutrition despite recent recovery from sepsis.
Monitor weekly weights and caloric intake to ensure adequate nutrition. 1
Consider high-protein oral supplements (e.g., Ensure Plus, Boost) between meals to increase protein intake without exacerbating hyperkalemia. 1
Ongoing Monitoring and Follow-Up
Potassium Monitoring Protocol
Check serum potassium and renal function (BMP) within 48 hours of initiating SZC, then weekly during dose titration. 1, 3 This patient has multiple risk factors requiring frequent monitoring: CKD stage 2, diabetes, atrial fibrillation, and recent hyperkalemia. 1
After stabilization: Check potassium at 1-2 weeks, 3 months, then every 6 months. 1, 3
If restarting lisinopril: Check potassium 7-10 days after restarting or increasing the dose. 1, 3
Medication Review
Review all medications for potential contributors to hyperkalemia:
NSAIDs: Avoid entirely, as they worsen renal function and increase hyperkalemia risk. 1, 3
Trimethoprim, heparin, beta-blockers: Review necessity and consider alternatives if possible. 1, 3
Potassium supplements or salt substitutes: Ensure patient is not using these. 1, 3
Diuretic Optimization
Consider adding or increasing loop diuretic (furosemide 40-80 mg daily) to increase urinary potassium excretion if adequate renal function is present (eGFR 63 is sufficient). 1, 3 This can help maintain normokalemia while allowing continuation of ACE inhibitor therapy. 1
Critical Pitfalls to Avoid
Do NOT permanently discontinue lisinopril due to hyperkalemia—this worsens cardiovascular and renal outcomes. 4, 1 Instead, use SZC to enable continuation of RAAS inhibition. 4, 1
Do NOT use sodium polystyrene sulfonate (Kayexalate) for chronic hyperkalemia management—it has limited efficacy data and serious gastrointestinal adverse effects (bowel necrosis). 1, 6 SZC and patiromer are superior alternatives. 1, 6
Do NOT delay treatment while waiting for repeat potassium levels if ECG changes are present—ECG changes indicate urgent need regardless of the exact potassium value. 1, 3
Do NOT rely solely on dietary restriction to manage hyperkalemia—it is insufficient as monotherapy and may worsen nutritional status in this patient with protein-calorie malnutrition. 1, 6
Monitor for hypokalemia after initiating SZC, as overcorrection can be more dangerous than mild hyperkalemia. 1, 3 Target potassium range is 4.0-5.0 mEq/L. 1, 3
Multifocal Pneumonia and Sepsis Management
Continue amoxicillin-clavulanate 875-125 mg PO BID through end of treatment date as planned. The patient is clinically improving (afebrile, stable oxygenation, no respiratory symptoms) and does not require escalation of antibiotic therapy. 1
Monitor weekly CBC to ensure WBC trend remains stable. 1
Continue pulmonary hygiene measures (incentive spirometry, upright positioning) to prevent recurrence. 1
Summary Algorithm
- Obtain ECG immediately → If changes present, give IV calcium gluconate. 1, 3
- Hold lisinopril temporarily until K+ <5.0 mEq/L. 1, 3
- Initiate SZC 10g TID × 48 hours, then 10g daily maintenance. 1, 2
- Check potassium within 48 hours, then weekly during titration. 1, 3
- Restart lisinopril at lower dose once K+ <5.0 mEq/L, with concurrent SZC. 1, 3
- Add SGLT2 inhibitor to reduce hyperkalemia risk and provide cardio-renal protection. 4, 1
- Optimize diuretic therapy (furosemide 40-80 mg daily) to increase urinary potassium excretion. 1, 3
- Check iron studies and supplement if deficient to address anemia. 7
- Continue nutritional support to correct protein-calorie malnutrition. 1
- Monitor potassium long-term at 1-2 weeks, 3 months, then every 6 months. 1, 3