Electrolyte Imbalances Flashcards
1
Q
What are causes of hypocalcaemia?
A
- Vit D deficiency
- CKD
- Acute pancreatitis
2
Q
How is hypocalcaemia managed?
A
- Oral calcium carbonate if mild
- IV calcium gluconate when severe (<1.9/seizures)
- ECG monitoring
3
Q
How does hypocalcaemia present?
A
- Muscle twitching, cramps and spasms
- Prolonged QT inverval
- Trousseau sign: carpal spasm when the brachial artery is occluded by inflating BP cuff and maintaining above systolic
- Chvostek sign: tapping over parotid causes facial twitch
4
Q
What causes hypercalcaemia?
A
- primary hyperparathyroidism
- malignancy e.g. lung, myeloma
5
Q
What is the key diagnostic investigation for hypercalcaemia?
A
PTH levels
6
Q
How does hypercalcaemia present?
A
- Bone pain
- Abdominal pain
- Renal stones
- Depression
- Drowsiness
- Delirium
- Muscle weakness
7
Q
How is hypercalcaemia managed?
A
- IV Saline
- IV Bisphosphonates
8
Q
What causes hyponatraemia?
A
- SIADH
- Hypothyroidism
- Thiazides
- Diarrhoea/Vomiting
- Psychogenic polydipsia
9
Q
How is hyponatraemia managed?
A
If hypovalaemia: IV fluids
If euvolaemic: Treat underlying cause e.g SIADH by fluid restriction
10
Q
What is the big risk with severe hyponatraemia?
A
Central pontine demyelination
11
Q
What are causes of hypernatraemia?
A
- Dehydration
- Osmotic diuresis
- Diabetes insipidus
12
Q
How is hypernatremia managed?
A
Rehydration with IV Saline/Hartmann’s - should not correct faster than 10mmol/24 hours due to risk of cerebral oedema
13
Q
What causes hypokalaemia?
A
- Diuretics
- Renal tubular acidosis
- Cushings/Conns
- Diarrhoea/vomiting
14
Q
How does hypokalaemia present?
A
- Muscle weakness
- Hypotonia
- ECG shows: U waves, small t waves, prolonged PR, ST depression
15
Q
How is hypokalaemia managed?
A
- Treat cause
- Oral supplementation if mild
- IV fluid if severe with cardiac monitoring
