1: Fluid + Electrolyte - Hypokalaemia Flashcards
What are the two causes of hypokalaemia
- Loss Potassium
- Intracellular shift potassium
What are the 4 broad-categories of potassium loss
- Renal-Loss
- Extra-renal Loss
- Medication
- Other
What are two renal causes of potassium loss
Conns
Cushings
What are two extra-renal causes of hypokalaemia
Diarrhoea
Vomitting
What two medications can cause hypokalaemia
Glucocorticoids
Liquorice
What is another cause of hypokalaemia
Low magnesium
What 3 things may cause hypokalaemia due to increasing intracellular shift
Insulin
Alkalosis
Salbutamol (B2 Agonist)
What are 3 symptoms of hypokalaemia
- Arrhythmias
- Muscle weakness: hypotonia, hyporeflexia
- Constipation
What is first-line investigation in hypokalaemia
ECG
What will be seen on ECG in hypokalaemia
- Flattened T waves
- ST depression
- U wave
What is the u wave
small wave following T-wave in lead V2
What defines mild hypokalaemia
<2.5 and asymptomatic
How is mild hypokalaemia managed
Oral potassium supplements
What defines severe hypokalaemia
> 2.5 or symptomatic
How is severe hypokalaemia managed
IV Potassium
What should IV potassium never be given as and why
Stat dose - if administered too quickly it causes vein damage and arrhythmias
When should IV potassium not be given
Oliguric
If interventions to correct potassium have been given, however it remains low, what is the likely cause
Low magnesium
