Potassium Flashcards
Normal potassium serum levels?
3.5-5.3mmol/L
Hyperkalaemia ECG changes? (3)
Small p waves,
Broadened QRS complex,
Tall tented T waves
3 main class causes of hyperkalamia?
Decreased renal excretion,
Redistribution,
Increased intake
Causes of decreased renal excretion causing hyperkalaemia? (4)
Renal failure,
ACE inhibitors,
Potassium sparing diuretics,
Addison’s disease
Causes of redistribution causing hyperkalaemia? (1)
Metabolic acidosis
Causes of increased intake causing hyperkalaemia? (3)
(Unlikely unless impaired renal excretion)
Over supplementation in IV fluids,
Over supplementation in TPN,
Blood transfusion
What is pseudohyperkalemia?
Potassium level is falsely elevated
Causes of pseudohyperkalemia? (4)
Haemolysis,
Delayed centrifugation,
Sample contamination (normally contaminated with EDTA potassium),
Increased platelet or white cell count
Treatment for hyperkalemia?
Calcium,
Insulin,
Glucose,
Nebulised salbutamol,
May need dialysis
ECG changes for hypokalaemia?
Flattened t waves,
U wave
Categories of causes of hypokalaemia? (3)
GI loss,
Renal loss,
Redistribution
GI loss causes of hypokalaemia? (4)
Villous adenoma,
Laxative abuse,
Prolonged severe vomiting or diarrhoea,
Intestinal fistula
Renal loss causes of hypokalaemia? (6)
Diuretics, Magnesium depletion, Cushing's syndrome, Conn's syndrome, Bartter's or Gitelman's syndrome, Renal tubular acidosis
Redistribution causes of hypokalaemia? (3)
Metabolic alkalosis,
Insulin (high dose),
B2 agonist eg salbutamol
Management of hypokalaemia?
Treat underlying cause,
Oral K+ replacement in mild,
IV K+ replacement if marked clinical features/ severe/ unresponsiveness to oral therapy/ ECG changes
