Hypocalcaemia ⬇️
Hypocalcaemia for NCHDs in Irish hospitals: adjusted calcium thresholds, oral Calcichew/Caltrate, IV calcium gluconate, and hypomagnesaemia.
🧠 Definition
- Adjusted (albumin-corrected) Ca²⁺: typical Irish ref. ≈2.2–2.6 mmol/L.
- Mild ≈1.9–2.2 (oral if asymptomatic); severe <1.9 or symptomatic at any level. Confirm local protocol.
- Correction often used: measured Ca²⁺ + 0.02 × (40 − albumin g/L). Consider ionised Ca²⁺ if acid–base disturbance.
🧾 Common causes
- Hypoparathyroidism / post-thyroid or parathyroid surgery
- Vitamin D deficiency; malabsorption; CKD
- Hypomagnesaemia: refractory until Mg²⁺ corrected
- Pancreatitis, rhabdomyolysis, tumour lysis
- Drugs: bisphosphonates, denosumab, cinacalcet, phenytoin, foscarnet; massive transfusion
🩺 Symptoms & ECG
- Mild: often asymptomatic; perioral / finger paraesthesia
- Cramps, carpopedal spasm, tetany, Chvostek / Trousseau
- Severe: seizures, laryngospasm, bronchospasm, confusion
- ECG: prolonged QTc. Monitor if severe or giving IV calcium
🔍 Investigations
- Adjusted Ca²⁺, albumin, phosphate, Mg²⁺, U&Es, ALP
- PTH and 25-OH vitamin D
- ECG if symptomatic, severe, or QTc concern
- Review neck surgery, nutrition, transfusions, bone-active drugs
💊 Management (Irish hospital practice)
- Confirm local protocol. Bands around 1.9 mmol/L are common (e.g. GGC); IV detail follows CUH / GUH pharmacy monographs.
- Asymptomatic mild (≈1.9–2.2): oral calcium first. Calcichew® 500 mg or Calcichew-D3® Forte; alternatives Caltrate® / Cadelius®.
- Severe (<1.9) or symptomatic: IV calcium gluconate 10% with ECG. 10–20 ml (~2.25–4.5 mmol), each 10 ml over ≥5 min via large vein; infusion if needed. Often unlicensed in Ireland: use hospital stock with pharmacy advice.
- Always correct hypomagnesaemia: common reason replacement fails.
- Do not co-infuse with phosphate, bicarbonate, or ceftriaxone; watch for extravasation.
- Post-neck surgery / hypoparathyroidism: urgent endocrine review. May need alfacalcidol plus oral calcium.
- Pancreatitis, sepsis, TLS: treat only if symptomatic or ECG-threatening.
📄 Product information (SmPC / HPRA)
Calcichew 500 mg chewable tablets: SmPC (HPRA PDF)Calcichew-D3 Forte Double Strength 1000 mg / 800 IU (HPRA)Caltrate 500 mg / 1000 IU chewable tablets (medicines.ie)Caltrate 600 mg / 400 IU film-coated tablets (medicines.ie)Cadelius 600 mg / 1,000 IU orodispersible tablets (medicines.ie)Calcium gluconate injection: HPRA (licence withdrawn; typically unlicensed hospital supply)
Calcium replacement
Common severity thresholds + Irish IV pharmacy detail. Always confirm local protocol
Adjusted Ca²⁺ bands (around 1.9) are common thresholds (e.g. GGC), not HSE/IAEM. Confirm local protocol. Correct Mg²⁺. IV detail follows CUH/GUH pharmacy monographs.
Note Template
Ready-to-use clinical note structure
🕒 08 / 10 / 2026 — 16:05 ATRP re: hypocalcaemia Patient: [age] [sex] Admission Dx: [reason for admission] PMHx: [neck surgery, CKD, vitamin D deficiency, pancreatitis, TLS] 🧾 Hx: • Paraesthesia, cramps, tetany, seizures • Post-thyroid/parathyroid surgery or bone-active drugs • Concurrent hypomagnesaemia 🩺 Exam: • Vitals: HR __ BP __ RR __ Temp __ SpO₂ __ • Neuromuscular: Chvostek / Trousseau, tetany • ECG / QTc if indicated 📋 Impression: Likely cause: [hypoparathyroidism / vit D / low Mg²⁺ / other] Adjusted Ca²⁺: __ mmol/L; Mg²⁺: __; phosphate: __; PTH/vit D: [pending] 📌 Plan: • Oral or IV calcium per protocol (ECG if IV / severe) • Correct hypomagnesaemia • Recheck adjusted Ca²⁺ after replacement • Endocrine / senior review if post-neck surgery or hypoparathyroidism suspected 👤 [Your Name], [Role] IMC: _______
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