Hypercalcaemia - Emergency Medicine Revision
Hypercalcaemia ranges from an asymptomatic biochemical abnormality to a life‑threatening metabolic emergency. The commonest causes are primary hyperparathyroidism and malignancy; drug‑related and vitamin D-mediated causes are important to recognise.
Emergency care focuses on rapid recognition, assessment for cardiac and renal complications, restoration of intravascular volume and early specialist liaison for definitive therapy.
At a glance - ED priorities
- Use albumin‑adjusted total calcium as the routine test; consider ionised calcium in critically ill patients or when albumin correction is unreliable.
- Repeat an abnormal value if ≥ 2.6 mmol/L (or ≥ 2.5 mmol/L with relevant clinical features) and measure parathyroid hormone (PTH) if the repeat result remains elevated (NICE NG132).
- Severity (practical ED thresholds):
- Mild: < 3.0 mmol/L - often asymptomatic; outpatient workup may be appropriate.
- Moderate: 3.0-3.5 mmol/L - symptoms common; treat if symptomatic or rising.
- Severe:
> 3.5 mmol/L - usually requires urgent correction (risk of arrhythmia, coma, renal failure) (RCEM/Endocrine guidance).
- Immediate actions for symptomatic or moderate-severe hypercalcaemia:
- Airway, breathing, circulation (ABCs), continuous ECG and cardiac monitoring.
- Restore intravascular volume with isotonic crystalloid (normal saline).
- Stop offending drugs (e.g., thiazides, vitamin D/ calcium supplements, lithium) and review recent bone‑targeted therapies (denosumab).