Endocrinology: Acute Hypocalcaemia Flashcards
Outline the pathophysiology of Hypocalcaemia
<2.12mmol/L
Outline the aetiology of hypocalcaemia
Rhabdomyolysis = release of excess phosphate that binds Ca
Hypoparathyroidism = low PTH – low osteoclast activity, low absorption in the intestine
CKD = decrease in the conversion of 25-hydroxyvitamin D to its active form 1,25-dihydroxyvitamin D
Hypomagnesaemia = low PTH release
Vit D def = necessary cofactor for PTH, low renders PTH ineffective
Phosphate normal or decreased
- Osteomalacia
- Acute pancreatitis
- Over-hydration
Outline the signs and symptoms of hypocalcaemia.
Mild = cramps, periorbital paraesthesia
Severe = carpopedal spasm, laryngospasm, seizures
Chronic = cataract, ECG long QT interval, skin changes - coarse hair, brittle nails, psoriasis
Trousseau sign = inflate BP cuff above systolic for 3 min, carpopedal spasm
Chvostek sign = tap facial N, twitch
How would you investigate hypocalcaemia?
Blood = Ca, PTH, phosphate, U+Es, CK, vit D, alk phos, magnesium
ECG
How would you manage hypocalcaemia?
Start treatment (give Ca) then investigate cause
◦ <1.9 or symptomatic - IV Ca gluconate
◦ >1.9 and asymptomatic - Ca supplements
If vit D low = high dose vit D
What are the complications of hypocalcaemia?
Laryngospasm
Arrhythmia
Osteoporosis = disability, fractures
Eye damage
Tetany
Seizure
