Hypocalcaemia Flashcards
When does symptomatic hypocalcaemia occur?
When calcium less than 1.9mmol/L or at higher values if rapid drop has occured
Commnest cause of hypocalcaemia
Post surgical hypoparathyroidism following thyroidectomy
Causes of hypocalcaemia
- Post surgery - thyroidectomy
- Vitamin D deficiency
- Hypomagnesaemia
Do pts often recover from post thyroidectomy hypoparathyroidism?
- Often temporary
- But may be permanent if damage or removal of parathyroid glands
- Long term f/u needed to assess if recovery of glands
How does Vitamin D deficiency present in neonate?
- Seizures
- Tetany
Biochemical test for vitamin D deficiency show
- Low phosphate
- Elevated PTH (unlike hypoparathyroidsm when it is high)
- Low calcium
PTH test results for hypomagnesaemia
Normal or low PTH
Causes of hypomagnesaemia
- GI loss
- Alcohol
- Drugs esp PPIs
Clinical features of hypocalcaemia - acute
- Laryngospasm
- Prolong QT interval
- Seizures
= medical emergency
Less acute hypocalcaemia
- Muscle cramps
- Carpo-pedal spasm
- Peri-oral and peripheral parasthesia
- Neuro-psychiatric symptoms
What is Chvosteks sign?
Facial spasm when the cheek is tapped lightly with finger
What is Trousseaus sign?
Carpo-pedal spasm induced after inflation of BP cuff
Treatment for hypocalcaemia - acute
- Calcium replacement
- IV calcium if acute
- If severe Vit D deficiency loading dose of cholecalciferol 20,000 IU per week for 7 weeks then maintenance dose
Treatment for hypoparathyroidism
- Alfacalcidol or Calcitriol (active VitD)
- Oral calcium supplements eg Sandocal and Adcal D3
Magnesium deficiency treatment - acute
- Precipitating drugs stopped
- IV magnesium started - MgSO4 24mmol/24hrs
If chronic GI loss or alcoholism cause, specialist input is given
