What is the guideline-directed algorithm for treating severe hyperkalemia (elevated potassium levels) in the Emergency Department (ED) for a patient with impending cardiac arrest due to hyperkalemia?

From the Guidelines

For severe hyperkalemia in an unstable patient in the emergency department, the guideline-directed algorithm involves administering calcium gluconate, insulin with glucose, sodium bicarbonate if metabolic acidosis is present, and nebulized albuterol to shift potassium into cells, followed by definitive removal of potassium using sodium polystyrene sulfonate or patiromer, and considering emergent hemodialysis if necessary, as outlined in the most recent and highest quality study 1.

Treatment Approach

The treatment of severe hyperkalemia aims to stabilize cardiac membranes, shift potassium into cells, and remove excess potassium from the body.

• Stabilize myocardial cell membrane with calcium gluconate 10% (10 mL IV over 2-3 minutes) which can be repeated after 5 minutes if ECG abnormalities persist, as recommended by 1.
• Shift potassium into cells using insulin (10 units of regular insulin IV push along with 25g of dextrose) and nebulized albuterol (10-20 mg over 15 minutes), with sodium bicarbonate (50 mEq IV over 5 minutes) if metabolic acidosis is present, as supported by 1.
• Remove excess potassium using sodium polystyrene sulfonate (Kayexalate) 15-30g orally or by retention enema, or patiromer 8.4g orally if available, and consider diuresis with furosemide or dialysis as outlined in 1.

Monitoring and Adjunctive Therapy

Throughout treatment, it is crucial to continuously monitor cardiac rhythm, vital signs, and repeat potassium levels every 2-4 hours.

• Adjunctive therapy may include adjuvant IV therapy as outlined for cardiotoxicity in addition to standard ACLS, as suggested by 1.
• The choice of treatment should be guided by the severity of hyperkalemia, the presence of ECG changes, and the patient's underlying medical conditions, with consideration of the potential for rebound hyperkalemia after initial treatment, as noted in 1.

From the Research

Guideline-Directed Algorithm for Treating Severe Hyperkalemia

The treatment of severe hyperkalemia, particularly in the context of impending cardiac arrest, is a medical emergency that requires immediate attention. The following steps outline the guideline-directed algorithm for managing severe hyperkalemia in the Emergency Department (ED):

• Stabilization of Cardiac Membranes: Administration of calcium gluconate (10% solution, 10 mL intravenously) to stabilize cardiomyocyte membranes and prevent cardiac arrhythmias 2, 3, 4.
• Transcellular Shift of Potassium: Use of insulin (usually with concomitant glucose) and beta-agonists (such as albuterol) to shift potassium into cells 2, 3, 5, 4.
• Removal of Potassium from the Body: Measures to facilitate the removal of potassium from the body, including:
  • Saline diuresis 2.
  • Oral binding resins (such as patiromer and sodium zirconium cyclosilicate) 3, 6.
  • Hemodialysis, which remains the most reliable method for removing potassium from the body 2, 3, 4.
• Monitoring and Adjunctive Therapy: Close monitoring of serum potassium levels, electrocardiography (ECG) changes, and clinical symptoms, with adjunctive therapy as needed, such as loop and thiazide diuretics 3.

Key Considerations

• The choice of treatment depends on the severity of hyperkalemia, the presence of ECG changes, and the patient's underlying medical conditions 2, 3, 5.
• Sodium polystyrene sulfonate is not recommended as a first-line treatment for acute hyperkalemia due to its limited efficacy 3, 6.
• Newer medications, such as patiromer and sodium zirconium cyclosilicate, may be useful in promoting gastrointestinal potassium excretion 3, 6.