Hyperkalemia | |
---|---|
Other names | Hyperkalaemia |
Electrocardiography showing precordial leads in hyperkalemia. | |
Pronunciation | |
Specialty | Critical care medicine, nephrology |
Symptoms | Palpitations, muscle pain, muscle weakness, numbness[1][2] |
Complications | Cardiac arrest[1][3] |
Causes | Kidney failure, hypoaldosteronism, rhabdomyolysis, certain medications[1] |
Diagnostic method | Blood potassium > 5.5 mmol/L, electrocardiogram[3][4] |
Differential diagnosis | Pseudohyperkalemia[1][2] |
Treatment | Medications, low potassium diet, hemodialysis[1] |
Medication | Calcium gluconate, dextrose with insulin, salbutamol, sodium bicarbonate[1][3][5] |
Frequency | ~2% (people in hospital)[2] |
Hyperkalemia is an elevated level of potassium (K+) in the blood.[1] Normal potassium levels are between 3.5 and 5.0 mmol/L (3.5 and 5.0 mEq/L) with levels above 5.5 mmol/L defined as hyperkalemia.[3][4] Typically hyperkalemia does not cause symptoms.[1] Occasionally when severe it can cause palpitations, muscle pain, muscle weakness, or numbness.[1][2] Hyperkalemia can cause an abnormal heart rhythm which can result in cardiac arrest and death.[1][3]
Common causes of hyperkalemia include kidney failure, hypoaldosteronism, and rhabdomyolysis.[1] A number of medications can also cause high blood potassium including spironolactone, NSAIDs, and angiotensin converting enzyme inhibitors.[1] The severity is divided into mild (5.5–5.9 mmol/L), moderate (6.0–6.4 mmol/L), and severe (>6.5 mmol/L).[3] High levels can be detected on an electrocardiogram (ECG).[3] Pseudohyperkalemia, due to breakdown of cells during or after taking the blood sample, should be ruled out.[1][2]
Initial treatment in those with ECG changes is salts, such as calcium gluconate or calcium chloride.[1][3] Other medications used to rapidly reduce blood potassium levels include insulin with dextrose, salbutamol, and sodium bicarbonate.[1][5] Medications that might worsen the condition should be stopped and a low potassium diet should be started.[1] Measures to remove potassium from the body include diuretics such as furosemide, potassium-binders such as polystyrene sulfonate (Kayexalate) and sodium zirconium cyclosilicate, and hemodialysis.[1] Hemodialysis is the most effective method.[3]
Hyperkalemia is rare among those who are otherwise healthy.[6] Among those who are hospitalized, rates are between 1% and 2.5%.[2] It is associated with an increased mortality, whether due to hyperkalaemia itself or as a marker of severe illness, especially in those without chronic kidney disease.[7][6] The word hyperkalemia comes from hyper- 'high' + kalium 'potassium' + -emia 'blood condition'.[8][9]