Key Points
            - Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
- Set objective targets and reassess frequently.
- Plan definitive source control or disease‑specific therapy when indicated; document follow‑up and patient education.
                                        Algorithm
            - ECG and repeat potassium; give IV calcium for ECG changes or K+ ≥6.5.
- Shift potassium with insulin/dextrose ± β-agonist ± bicarbonate (if acidotic).
- Remove potassium with binders/diuretics/dialysis; identify and treat underlying cause; continuous monitoring.
                                        Clinical Synopsis & Reasoning
            Treat hyperkalemia with a three-step sequence: stabilize cardiac membrane (IV calcium), shift K+ intracellularly (insulin/dextrose, β-agonists, bicarbonate if acidotic), and remove K+ (diuretics, potassium binders, or dialysis). Continuous ECG monitoring is essential.
                                        Treatment Strategy & Disposition
            Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced/procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.
                                        Epidemiology / Risk Factors
            - Risk varies by comorbidity and precipitants; see citations for condition‑specific data.
                                        Investigations
            
              
                | Test | Role / Rationale | Typical Findings | Notes | 
|---|
                
                  | Immediate ECG and repeat potassium level | Risk | Identify life-threatening changes | Confirm true elevation | 
| Chemistries/ABG and review of meds | Etiology | Acidosis, renal failure, ACEi/ARBs, K+ supplements | Address causes | 
| Urine electrolytes (selected) | Mechanism | Hypoaldosteronism vs renal failure | — | 
                
              
             
                                        High-Risk & Disposition Triggers
            
              
                | Trigger | Why it matters | Action | 
|---|
                
                  | ECG changes (peaked T, widening QRS) | Arrhythmia risk | IV calcium immediately; telemetry | 
| K+ ≥6.5 mEq/L or rising rapidly | Life-threatening | Full temporizing cocktail; ICU | 
| Renal failure or rhabdomyolysis | Refractory elevation | Dialysis early | 
| Digoxin toxicity | Calcium risk debated | Use Digibind; careful with calcium | 
| Hemolysis suspected | Pseudohyperkalemia | Repeat plasma level quickly | 
                
              
             
                                        Pharmacology
            
              
                | Medication/Intervention | Mechanism | Onset | Role in Therapy | Limitations | 
|---|
                
                  | Calcium gluconate 1–2 g IV (repeat as needed) | Membrane stabilization | Minutes | Protects myocardium | Use chloride via central line | 
| Regular insulin 10 U IV + D25W 25 g (or D50W 50 mL) | Intracellular shift | Minutes | Lowers K+ ~0.6–1.0 mEq/L | Monitor glucose | 
| Nebulized albuterol 10–20 mg | β2-agonist | Minutes | Adjunct shift | Tachycardia/tremor | 
| Sodium bicarbonate (if acidotic) | Buffer | Minutes | Shift in metabolic acidosis | Limited in euvolemic patients | 
| Sodium zirconium cyclosilicate 10 g or Patiromer 8.4–25.2 g | Removal (GI binders) | Hours | Non-emergent removal | Avoid in bowel obstruction | 
| Loop diuretics and/or hemodialysis | Removal | Hours | Definitive in renal failure | — | 
                
              
             
                                        Prognosis / Complications
            - Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.
                                        Patient Education / Counseling
            - Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.
                  
        
                  References
                      - Nephrology emergency hyperkalemia guidance — Link