Long-term changes in parathyroid function after subtotal thyroidectomy for graves' disease.
ABSTRACT Transient hypocalcemia is one of the postoperative complications of thyroidectomy for Graves' disease, and perioperative parathyroid hormone (PTH) assays are used to predict postoperative hypocalcemia. We evaluated long-term changes in parathyroid function after surgery for Graves' disease.
Serum PTH values were measured in Graves' patients with postoperative hypocalcemia, and those patients were followed postoperatively.
Subtotal thyroidectomy was performed in 275 patients with Graves' disease. Their serum calcium levels were measured on postoperative day (POD) 1, and patients with transient postoperative hypocalcemia were treated with calcium and vitamin D supplementation and followed up. The amount of calcium and vitamin D supplementation was adjusted to keep the patient's serum calcium level within the normal range. Measurement of their serum intact PTH value on POD 1 revealed normal value in 18 patients, a below normal level in 22, and an above normal level in the other 2. During the follow-up period, the serum iPTH values remained normal in 12 patients, recovered to the normal level in 21 patients, and rose above the normal range in 9 patients. The serum iPTH values of all patients eventually reached the normal range during the follow-up period. A marked difference in preoperative serum alkaline phosphatase concentration was observed between the high-iPTH patients and the normocalcemic patients.
The phenomenon of an elevated serum PTH level after surgery for Graves' disease was observed in 21% of the patients with postoperative hypocalcemia despite the achievement of normal serum calcium levels by calcium and vitamin D supplementation.
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ABSTRACT: Oral calcium and calcitriol are often prescribed after total thyroidectomy to avoid biochemical and/or symptomatic hypocalcemia. We aimed to identify independent perioperative factors that correlated with the duration of calcium and/or calcitriol supplementation after total thyroidectomy. Of 271 eligible patients, 48 (17.7 %) required calcium and/or calcitriol supplements on discharge. Patients were gradually weaned from the supplementation by one surgeon according to a biweekly algorithm based on serum calcium (Ca). Duration of supplementation was calculated from the date of operation to the date of ceasing all supplementation without biochemical hypocalcemia (i.e., serum adjusted Ca ≥8.44 mg/dL). The Cox regression analysis was performed to identify independent perioperative factors for duration of supplementation. The best cut-off value for these independent factors was determined by the receiver characteristic curve. In the multivariate analysis, parathyroid hormone (PTH) at skin closure (PTH-SC) (RR 1.742, 95 % CI 1.080-2.810) and on postoperative day 1 adjusted Ca (Ca-D1) (RR 77.526, 95 % CI 3.600-1669.57) were the only two independent determinants for shorter duration before ceasing all supplementation. The best cut-off values in predicting supplementation ≥6 months for PTH-SC and Ca-D1 were 7.08 pg/mL (sensitivity = 100 %, specificity = 60.5 %, PPV = 40.0 % and NPV = 100 %) and 7.88 mg/dL (sensitivity = 90.0 %, specificity = 55.3 %, PPV = 34.6 % and NPV = 95.5 %), respectively. Both PTH-SC and Ca-D1 were independently associated with the duration of supplementation after total thyroidectomy. Almost all patients with PTH-SC ≥7.08 pg/mL or Ca-D1 ≥7.88 mg/dL did not require supplementation ≥6 months whereas about one third of patients with PTH-SC <7.08 pg/mL or Ca-D1 <7.88 mg/dL required supplementation ≥6 months.World Journal of Surgery 08/2013; · 2.23 Impact Factor
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ABSTRACT: Thyroidectomy is the most common endocrine surgical procedure being carried out throughout the world. Besides, many patients who have deranged thyroid physiology, namely hyperthyroidism and hypothyroidism, have to undergo various elective and emergency surgical procedures at some stage of their life. The attending anesthesiologist has to face numerous daunting tasks while administering anesthesia to such patients. The challenging scenarios can be encountered at any stage, be it preoperative, intra-op or postoperative period. Preoperatively, deranged thyroid physiology warrants optimal preparation, while anticipated difficult airway due to enlarged thyroid gland further adds to the anesthetic challenges. Cardiac complications are equally challenging as also the presence of various co-morbidities which make the task of anesthesiologist extremely difficult. Thyroid storm can occur during intra-op and post-op period in inadequately prepared surgical patients. Postoperatively, numerous complications can develop that include hemorrhage, laryngeal edema, nerve palsies, tracheomalacia, hypocalcemic tetany, pneumothorax, etc., The present review aims at an in-depth analysis of potential risk factors and challenges during administration of anesthesia and possible complications in patients with thyroid disease.Indian journal of endocrinology and metabolism. 03/2013; 17(2):228-34.