A 58 year old man on haemodialysis presents with profound weakness after a weekend fishing trip.
This man's serum potassium was 9.6 mmol/L.
Hyperkalaemia
The following changes may be seen in hyperkalaemia
- small or absent P waves
 - atrial fibrillation
 - wide QRS
 - shortened or absent ST segment
 - wide, tall and tented T waves
 - ventricular fibrillation