Hyperkalaemia

Question 1

Which conditions might cause hyperkalaemia?

Answer 1

AKI
CKD
Rhabdomyolysis
Adrenal insufficiency
Tumour lysis syndrome

Question 2

Which medications might cause hyperkalaemia?

Answer 2

Aldosterone antagonists (spironolactone + eplerenone)
ACE inhibitors
ARBs
NSAIDs
Potassium supplements

Question 3

What might cause a falsely elevated potassium on a blood test?

Answer 3

Haemolysis during sampling

- lab might indicate need for a repeat sample

Question 4

What are the ECG changes in hyperkalaemia?

Answer 4

Tall tented T waves
Flattened or absent P waves
Broad QRS complexes

Question 5

When does a patient require urgent treatment for hyperkalaemia?

Answer 5

Potassium >/= 6 with ECG changes

Potassium >/= 6.5 regardless of ECG

Question 6

What is the mainstay of treatment for hyperkalaemia?

Answer 6

Insulin + dextrose infusion

+ IV calcium gluconate

Question 7

What is the role of insulin + dextrose solution in the management of hyperkalaemia?

Answer 7

Drives potassium back into cells

Question 8

What is the role of calcium gluconate in the management of hyperkalaemia?

Answer 8

Stabilises the cardiac myocytes, reducing the risk of arrhythmias
(no effect on potassium)

Question 9

What are the other options for lowering potassium in hyperkalaemia?

Answer 9

Nebulised salbutamol
IV fluids
Oral calcium resonium (works slowly)
Sodium bicarbonate (if acidotic)
Dialysis