Postoperative hypocalcemia from inadvertent parathyroid removal or ischemia is the most common life-threatening complication after total thyroidectomy. Symptoms appear when ionized calcium drops below 1.0 mmol/L (or total serum calcium below 8 mg/dL): perioral and fingertip paresthesias, positive Chvostek (facial twitch on cheek tap), positive Trousseau (carpal spasm on BP cuff inflation), muscle cramps, laryngospasm, seizures, and prolonged QT with torsades. Treatment of symptomatic acute hypocalcemia: (1) calcium gluconate 1 to 2 g IV, dilute in 50 to 100 mL D5W (NS is acceptable but D5W is commonly used), and infuse over 10 to 20 minutes — never IV push because rapid administration causes bradyarrhythmia and cardiac arrest, (2) use a large patent peripheral IV or central line; calcium is a vesicant and infiltration causes severe tissue necrosis (extravasation antidote: stop, aspirate, hyaluronidase if available), (3) place the client on continuous cardiac monitor and follow QT, (4) check ionized calcium, total calcium, magnesium (low Mg perpetuates hypocalcemia and must be repleted), albumin, and phosphate, (5) avoid mixing calcium with sodium bicarbonate or phosphate-containing fluids because of precipitation. IM calcium is contraindicated. Ongoing therapy: oral calcium plus vitamin D, possibly calcitriol, and parathyroid hormone monitoring. Airway management readiness for laryngospasm.
In-depth explanation
IV calcium gluconate is always diluted, infused slowly, and given through a large-bore line with cardiac monitoring. The two NCLEX trap behaviors are pushing it fast and mixing it with sodium bicarbonate (precipitates).
For study reference only. Always follow current clinical guidelines and your institution’s protocols.