Hyperkalaemia

Question 1

What is hyperkalaemia?

Answer 1

High serum potassium; associated with cardiac arrhythmias

Question 2

What are some conditions that can cause hyperkalaemia?

Answer 2

• Acute kidney injury
• Chronic kidney disease
• Rhabdomyolysis
• Adrenal insufficiency
• Tumour lysis syndrome

Question 3

What are some medications that can cause hyperkalaemia

Answer 3

• Aldosterone antagonists (spironolactone and eplerenone)
• ACE inhibitors
• Angiotensin II receptor blockers
• NSAIDs
• Potassium supplements

Question 4

How may hyperkalaemia present?

Answer 4

When present, the symptoms of hyperkalemia are nonspecific and predominantly related to muscular or cardiac function - fatigue, muscle weakness, palpatations/chest pain

Question 5

What investigations are required in hyperkalaemia?

Answer 5

Bloods
ECG

Question 6

What bloods are required in hyperkalaemia?

Answer 6

U+Es - potassium, creatinine, urea, eGFR

Question 7

What will ECG show in hyperkalaemia?

Answer 7

• Tall peaked T waves
• Flattening or absence of P waves
• Broad QRS complexes

Question 8

What is the 1st line management of hyperkalaemia?

Answer 8

• Cardiac monitor and IV access
• insulin and dextrose infusion and IV calcium gluconate
  
  • 10 mls 10% calcium gluconate (2-3 mins) - protects myocardium
  • Insulin (actrapid 10 units) with 50mls 50% dextrose (30 mins) - moves K+ back into cells

Question 9

What are some other management options in hyperkalaemia?

Answer 9

• Salbutamol neb (90 mins) - temporarily drives potassium into cells
• Sodium bicarbonate if acidotic
• In chronic hyperkalaemia (not used in acute setting) - calcium resonuim to prevent absorption from GI tract
• IV fluids can be used to increase urine output, which encourages potassium loss from the kidneys (but don’t fluid overload patients with renal failure)