What causes hyperkalemia?

From the Guidelines

Hyperkalemia, in this case with a potassium level of 5.6 mEq/L, is most likely caused by kidney dysfunction or medications such as ACE inhibitors, ARBs, potassium-sparing diuretics, and NSAIDs, which can impair potassium excretion or increase potassium levels in the blood. The risk factors for hyperkalemia include chronic kidney disease (CKD), diabetes, heart failure (HF), and the use of renin-angiotensin-aldosterone system inhibitors (RAASis) 1. Other significant causes of hyperkalemia include massive cell destruction, acidosis, insulin deficiency, and excessive potassium intake through supplements or salt substitutes 1.

Common Causes of Hyperkalemia

• Kidney dysfunction, which impairs potassium excretion
• Medications like ACE inhibitors, ARBs, potassium-sparing diuretics (spironolactone, eplerenone), and NSAIDs
• Massive cell destruction (rhabdomyolysis, tumor lysis syndrome, severe burns)
• Acidosis
• Insulin deficiency
• Excessive potassium intake through supplements or salt substitutes
• Adrenal insufficiency due to decreased aldosterone production
• Certain medical conditions like type 4 renal tubular acidosis and pseudohyperkalemia (a laboratory artifact from hemolysis during blood collection)

Management and Treatment

The management of hyperkalemia depends on the severity of the condition and may include treatments such as calcium gluconate, insulin with glucose, beta-agonists, or dialysis in severe cases 1. It is essential to monitor serum creatinine and potassium levels during treatment with ACE inhibitors, ARBs, or diuretics, especially in patients with reduced glomerular filtration 1.

Key Considerations

• Hyperkalemia can lead to life-threatening cardiac conduction abnormalities, requiring immediate medical attention.
• The symptoms of hyperkalemia can be nonspecific and may include muscle weakness, cardiac arrhythmias, and paresthesias.
• Treatment options for acute hyperkalemia include intravenous calcium gluconate, insulin/glucose, inhaled β-agonists, intravenous sodium bicarbonate, and hemodialysis 1.

From the Research

Causes of Hyperkalemia

The causes of hyperkalemia, a condition where potassium levels in the blood exceed 5.0 mmol/L, can be multifaceted. Some of the key factors include:

• Inability of the kidneys to excrete potassium 2
• Impairment of the mechanisms that move potassium from the circulation into the cells 2
• Introduction of medications affecting potassium homeostasis, such as angiotensin-converting enzyme inhibitors, potassium-sparing diuretics, and renin-angiotensin-aldosterone-system (RAAS) inhibitors 3, 4, 5
• High dietary intake of potassium, especially in patients taking medications that predispose to hyperkalemia 3
• Decreased renal function, expressed as estimated glomerular filtration rate (eGFR) <50 ml/min 4
• Illness or dehydration 2
• Use of certain drugs that can cause hyperkalemia by promoting transcellular potassium shift or impairing renal potassium excretion 5

Risk Factors

Several risk factors can contribute to the development of hyperkalemia, including:

• Diabetes mellitus 4
• Congestive heart failure 4
• Advanced age 4
• Gender 4
• Use of heparin, digoxin, non-steroidal anti-inflammatory drugs, beta-blockers, calcineurin antagonists, and trimethoprim 4
• Decreased renal function (eGFR <50 ml/min) 4

Drug-Induced Hyperkalemia

A wide range of drugs can cause hyperkalemia, including:

• Angiotensin-converting enzyme inhibitors 5
• Angiotensin-II receptor blockers 5
• Direct renin inhibitors 5
• Nonsteroidal anti-inflammatory drugs 5
• Calcineurin inhibitors 5
• Heparin and derivatives 5
• Aldosterone antagonists 5
• Potassium-sparing diuretics 5
• Trimethoprim 5
• Pentamidine 5
• Potassium-containing agents 5