- Perioral and digital paraesthesia
- Cardiac disturbances
- Impaired cardiac contractility
- CNS disturbances
- Lack of vitamin D
- Drugs (eg bisphosphonates)
- Hyperventilation. Plasma proteins, especially albumin, have negatively-charged anionic residues which act as buffers. Alkalosis shifts the equilibrium towards the negatively-charged forms, increasing calcium binding and reducing free calcium.
- Malignancy (breast/prostate with sclerotic bony lesions)
Dependent on cause!
Oral calcium supplements are normally sufficient, unless there are worrying clinical features. Vitamin D supplements are also helpful.
In acute hypocalcaemia severe enough to cause tetany a soluble preparation such as calcium gluconate 10% is given slowly: (typically for an adult 10ml but see local protocols as there is likely to be a need for continuous infusion of up to 9mmol/day until other measures kick in and children need a dose calculation).
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