HYPOCALCEMIA

Question 1

MANAGEMENT

Answer 1

CALCIUM GLUCONATE

MILD (serum ionized calcium 1-1.2 mmol/L): 1-2 g as a continuous IV infusion over 2 hours.

MODERATE (serum ionized calcium <1 mmol/L): 4 g as a continuous IV infusion over 4 hours.

SEVERE SYMPTOMATIC (serum ionized calcium level <0.9 mmol/L, seizures, or tetany): 1-2 g as an IV infusion over 10 minutes. Repeat q hr while monitoring calcium levels until symptoms resolve.

REPLACE MAGNESIUM

CALCIUM CHLORIDE

MILD (serum ionized calcium level 1-1.2 mmol/L): 0.67 g as an IV infusion over 2 hours.

MODERATE (serum ionized calcium level <1 mmol/L): 1.3 g as an IV infusion over 4 hours.

SEVERE, SYMPTOMATIC (serum ionized calcium level <0.9 mmol/L), seizures, or tetany): 1 g as an IV infusion over 10 minutes. The dose can be repeated every hour until symptoms resolve.

REPLACE MAGNESIUM

MILD SYMPTOMS: corrected calcium level >1.9 mmol/L:
Calcium Carbonate 1000 mg PO bid

INVESTIGATIONS:
CBC
Mag
Phos
Ionized Calcium
Parathyroid Hormone
Lipase
ECG

MONITOR: CARDIOPULMONARY
Neuromuscular Weakness
Torsades de Pointes
Heart Failure
Ventricular Arrythmias
Seizure

Question 2

DOCUMENTATION

Answer 2

CLINICAL FEATURES
Weakness
Spasms / Cramps
Tetany
Circumoral and digital paresthesias
Seizure

HISTORY
Ask about:
Abdominal Pain / Vomit (pancreatitis)
Recent Thyroidectomy

PHYSICAL EXAM
Check:
Chvostek Sign (facial muscle twitching with percussion over the facial nerve).
Trousseau Sign: (carpal spasm with BP cuff inflation).

ECG
QT Prolongation