Postoperative calcium supplementation in patients undergoing thyroidectomy :

Postoperative hypocalcemia is a common and most often transient event after extensive thyroid surgery. It may reveal iatrogenic injury to the parathyroid glands and permanent hypoparathyroidism. We prospectively evaluated the incidence of hypocalcemia and permanent hypoparathyroidism following total or subtotal thyroidectomy in 1071 consecutive patients operated during 1990-1991. We then determined in a cross-sectional study which early clinical and biochemical characteristics of patients experiencing postoperative hypocalcemia correlated with the long-term outcome. Postoperative calcemia under 2 mmol/l was observed in 58 patients (5. 4%). In 40 patients hypocalcemia was considered severe (confirmed for more than 2 days, symptomatic or both). At 1 year after surgery five patients (0.5%) had persistent hypocalcemia. We found that patients carried a high risk for permanent hypoparathyroidism if fewer than three parathyroid glands were preserved in situ during surgery or the early serum parathyroid hormone level was /= 4 mg/dl under oral calcium therapy. When one or more of these criteria are present, long-term follow-up should be enforced to check for chronic hypocalcemia and to avoid its severe complications by appropriate supplement therapy.

There has been renewed interest in extensive lymph node dissection for papillary thyroid cancer (PTC), and a number of reports have been published concerning compartment-oriented dissection of regional lymph nodes in PTC. A comprehensive review of this body of literature using evidence-based methodology is pending. Systematic review of the literature using evidence-based criteria. Issue 1: Systematic compartment-oriented central lymph node dissection (CLND) may decrease recurrence of PTC (Levels IV and V data, no recommendation) and likely improves disease-specific survival (grade C recommendation). Limited level III data suggest survival benefit with the addition of prophylactic dissection to thyroidectomy (grade C recommendation). The addition of CLND to total thyroidectomy can significantly reduce levels of serum thyroglobulin and increase rates of athyroglobulinemia (level IV data, no recommendation). Issue 2: There may be a higher rate of permanent hypoparathyroidism and unintentional permanent nerve injury when CLND is performed with total thyroidectomy than for total thyroidectomy alone (grade C recommendation). Issue 3: Reoperation in the central neck compartment for recurrent PTC may increase the risk of hypoparathyroidism and unintentional nerve injury when compared with total thyroidectomy with or without CLND (grade C recommendation), supporting a more aggressive initial operation. Evidence-based recommendations support CLND for PTC in patients under the care of experienced endocrine surgeons.

The purpose of this study was to evaluate the clinical usefulness of routine oral calcium and vitamin D supplements in the prevention of hypocalcemia after total thyroidectomy. Ninety patients who underwent total thyroidectomy were randomly assigned to routinely receive or not receive a supplement containing oral calcium (3 g/d) and vitamin D (1 g/d) for 2 weeks. Hypocalcemic signs and symptoms, serum calcium, and parathyroid hormone (PTH) levels were monitored and compared between the 2 groups. The incidences of symptomatic and laboratory hypocalcemia were significantly lower in the oral calcium/vitamin D group than in the group not receiving the supplement: 3 of 45 patients (7%) versus 11 of 45 (24%) and 6 of 45 (13%) versus 16 of 45 (36%), respectively (P < or = .02). The hypocalcemic symptoms were minimal in the supplement group but more severe in the group not receiving the supplement. Serum calcium levels decreased in both groups after surgery but recovered earlier in the supplement group. No hypercalcemia or PTH inhibition developed in the supplement group. Routine administration of a supplement containing oral calcium and vitamin D is effective in reducing the incidence and severity of hypocalcemia after total thyroidectomy.