Sywak Mark S, Palazzo Fausto F, Yeh Michael, Wilkinson Margaret, Snook Kylie, Sidhu Stan B, Delbridge Leigh W
Department of Surgery, University of Sydney Endocrine Surgical Unit, Royal North Shore Hospital, St Leonards, New South Wales, Australia.
ANZ J Surg. 2007 Aug;77(8):667-70. doi: 10.1111/j.1445-2197.2007.04183.x.
Postoperative parathyroid gland function after total thyroidectomy (TT) has traditionally been monitored by the measurement of serum calcium concentrations. The purpose of this study is to determine whether measurement of parathyroid hormone (PTH) concentrations in the early postoperative period accurately predicts patients at risk of developing hypocalcaemia.
A prospective cohort study of patients undergoing TT was carried out. PTH concentrations were measured preoperatively and at 4 and 23 h postoperatively. Serum calcium concentration was measured preoperatively and twice daily for 48 h after surgery.
One hundred patients undergoing TT were recruited into the study in the period June 2004 to July 2005. Benign multinodular goitre was the most common indication for surgery (77%). The incidence of temporary hypocalcaemia (Ca < 2.0 mmol/L) was 18%. The mean PTH concentration at 4 h after surgery was 22.3 ng/L and was not significantly different from the 23-h concentration of 23.2 ng/L (P = 0.18). A PTH concentration of < or = 3 ng/L measured at 4 h after surgery had a sensitivity, specificity and likelihood ratio of 0.71, 0.94 and 11.3, respectively, for predicting postoperative hypocalcaemia. The accuracy of a single PTH concentration at 4 h was good for predicting hypocalcaemia (area under receiver-operator characteristic curve 0.90; confidence interval 0.81-0.96). There was no significant difference in accuracy between the 4- and 24-h PTH concentrations (P = 0.14).
A single measurement of PTH concentration in the early postoperative period after TT reliably predicts patients who are likely to develop hypocalcaemia. This approach facilitates early discharge and may decrease the need for multiple postoperative blood tests.
传统上，全甲状腺切除术后甲状旁腺功能是通过测量血清钙浓度来监测的。本研究的目的是确定术后早期甲状旁腺激素（PTH）浓度的测量能否准确预测有发生低钙血症风险的患者。
对接受全甲状腺切除术的患者进行了一项前瞻性队列研究。术前、术后4小时和23小时测量PTH浓度。术前和术后48小时每天测量两次血清钙浓度。
2004年6月至2005年7月期间，100例接受全甲状腺切除术的患者被纳入研究。良性多结节性甲状腺肿是最常见的手术指征（77%）。暂时性低钙血症（Ca<2.0 mmol/L）的发生率为18%。术后4小时的平均PTH浓度为22.3 ng/L，与术后23小时的23.2 ng/L浓度无显著差异（P = 0.18）。术后4小时测量的PTH浓度≤3 ng/L，预测术后低钙血症的敏感性、特异性和似然比分别为0.71、0.94和11.3。术后4小时单次PTH浓度预测低钙血症的准确性良好（受试者工作特征曲线下面积为0.90；置信区间为0.81 - 0.96）。术后4小时和24小时PTH浓度的准确性无显著差异（P = 0.14）。
全甲状腺切除术后早期单次测量PTH浓度能够可靠地预测可能发生低钙血症的患者。这种方法有助于早期出院，并可能减少术后多次血液检查的必要性。
