Hyperkalemia resident survival guide

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Rim Halaby, M.D. [2]; Mahmoud Sakr, M.D. [3]

Definition

Hyperkalemia is defined as a serum potassium concentration greater than 5.5 mEq/L in adults. Levels higher than 7 mEq/L can lead to significant hemodynamic compromise.

Causes

Life Threatening Causes

Life-threatening causes include conditions which may result in death or permanent disability within 24 hours if left untreated.

• Acute renal failure
• Adrenal insufficiency
• Diabetic ketoacidosis
• Large IV doses of calcium chloride or calcium gluconate
• Massive hemolysis
• Metabolic acidosis
• Rapid tissue necrosis
• Rhabdomyolysis
• Tumor lysis syndrome

Common Causes

• Adrenal insufficiency
• Blood transfusion
• Diabetic ketoacidosis
• Potassium supplementation (oral or IV)
• Potassium rich diet
• Medications: ACE inhibitors, angiotensin receptor blockers, amiloride, spironolactone, NSAIDS, ciclosporin, tacrolimus, trimethoprim, pentamidine, succinylcholine
• Pseudohyperkalemia
• Renal insufficiency
• Renal tubular acidosis type 4

Management

Shown below is an algorithm summarizing the approach to hyperkalemia.

Potassium > 5.5 mEq/L

If repeated potassium level is normal, check potassium level in 24 hours

R/O Pseudohyperkalemia (Artifact, hemolysis, elevated WBC, elevated RBC, elevated platelets) Repeat potassium level

Check vital signs ABC's Order an EKG Obtain a concise history and physical exam Order BUN, creatinine, glucose, ABG

Assess EKG

Presence of EKG changes Loss of P waves, peaked T waves and wide QRS

Absence of EKG changes and Hemodynamically stable patient

Do the following steps simultaneously: 1. Myocardial stabilization IV Ca gluconate (1-2 amps) Contraindicated in digoxin toxicity and hypercalcemia 2. Shift potassium from blood into cells Insulin (0.2 units for every gram of glucose administered) and 20% dextrose ( 2.5-5 ml/kg/h) Glucose level monitoring is needed Beta2 agonists (albuterol is given 10-20mg via nebulizer or 0.5 mg IV) 3. Lower total body potassium Cation exchange resin (kayexalate 30-90g given P.O. or P.R.) Loop diuretics (furosemide 1-2 mg/kg) Hemodialysis if refractory

Potassium > 6 mEq/L

5.5mEq/L<Potassium<6mEq/L

Do the following steps simultaneously: 1. Monitor for cardiac arrhythmia Place the patient on a closely monitored bed for potential arrhythmias 2. Shift potassium from blood into cells Insulin (0.2 units for every gram of glucose administered) and 20%dextrose ( 2.5-5 ml/kg/h) Glucose level monitoring is needed Beta2 agonists (albuterol is given 10-20mg via nebulizer or 0.5 mg IV) 3. Lower total body potassium Cation exchange resin (kayexalate 30-90g given P.O. or P.R. Loop diuretics (furosemide 1-2 mg/kg) Hemodialysis if refractory

Lower total body potassium Cation exchange resin (kayexalate 30-90g given P.O. or P.R.) Loop diuretics (furosemide 1-2 mg/kg)

D/C any offending medications that is associated with hyperkalemia D/C oral or parenteral potassium Correct acidosis with bicarb if pH<7.2 Restrict dietary potassium intake Review potassium levels every 2-4 hours until stabilized Check levels of other electrolytes such as magnesium and phosphorus