Calcium (total)
BMP / ElectrolytesNormal range
9.0–10.5 mg/dL
SI: 2.25–2.62 mmol/L
Critical low: < 6.5 mg/dL · Critical high: > 13 mg/dL
☎ When to call
Ca < 7.5 with tingling/spasm (or any post-neck-surgery patient with these), or > 12 with confusion — call the provider.
What you do
- Low albumin falsely lowers total Ca — corrected Ca = total + 0.8 × (4 − albumin), or use ionized
- Low: Trousseau/Chvostek signs, tetany, laryngospasm watch — especially post-thyroidectomy
- High: hydrate, mobilize, safety (confusion, weakness)
Causes of HIGH calcium
Causes of LOW calcium
Source: Pagana, Mosby's Manual of Diagnostic and Laboratory Tests, 7th ed.Reference only — verify against your facility's policy.
