Jiang Wen, Lee Euyhyun, Newfield Ron S
Department of Surgery - Division of Otolaryngology, University of California San Diego, Rady Children's Hospital in San Diego, San Diego, CA, USA.
Altman Clinical and Translational Research Institute, University of California San Diego, La Jolla, CA, USA.
Int J Pediatr Otorhinolaryngol. 2019 Oct;125:153-158. doi: 10.1016/j.ijporl.2019.07.006. Epub 2019 Jul 12.
Hypocalcemia is a common complication after thyroidectomy. Intact parathyroid hormone (PTH) has been successfully used as a predictive indicator for hypocalcemia in adults during the postoperative period. We aim to demonstrate the utility of PTH in predicting and managing postoperative hypocalcemia following thyroidectomy in pediatrics.
The study is a retrospective case series including 38 patients up to 18 years of age who underwent total or completion thyroidectomy from 1/1/2010 to 12/31/2016 at a tertiary pediatric academic center. Patient demographics, pathology, postoperative PTH, serum calcium, and length of stay were analyzed.
The median age was 14.3 years (range of 4.3-18.4 years) with 84.2% being female. Thyroid malignancy was noted in 25 patients, and 13 had benign pathology including 8 patients with multinodular goiter and 5 with Grave's disease. In this serie, 63.2% (24/38) developed hypocalcemia (serum calcium <8.5 mg/dL) postoperatively. The median PTH of 15.8 pg/mL in the hypocalcemic group was significantly lower than the median PTH of 41.6 pg/mL in the normocalcemic group (p < 0.001). Using a PTH threshold of 26 pg/mL, hypocalcemia was predicted with a sensitivity of 75%, and specificity of 100%. Six patients with calcium <7.5 mg/dL received teriparatide injections to avoid intravenous calcium replacement. The length of hospital stay for normocalcemic patients was 1.7 ± 0.8 days vs. 2.9 ± 1.4 days for hypocalcemic patients (p = 0.002). We found no correlation between the incidence of hypocalcemia and pathologic indication for surgery. Completion thyroidectomy was associated with a lower risk of hypocalcemia when compared to total thyroidectomy (p = 0.01) and neck dissections carried an increased risk of postoperative hypocalcemia (p = 0.04).
Postoperative PTH level has an excellent specificity in predicting hypocalcemia in this pediatric cohort using a threshold of PTH ≤ 26 pg/mL. Those with PTH >26 pg/mL may avoid hypocalcemia by oral calcium replacement with outpatient follow-up. We did not identify a reliable PTH cutoff value above which pediatric patients may be safely discharged immediately following surgery. Adult guideline or pathways that advocate for outpatient thyroidectomy surgery based on normal PTH ≥10 pg/mL in the recovery room may not apply to children.
低钙血症是甲状腺切除术后常见的并发症。完整甲状旁腺激素（PTH）已成功用作成人术后低钙血症的预测指标。我们旨在证明PTH在预测和管理儿科甲状腺切除术后低钙血症中的作用。
本研究为回顾性病例系列，纳入了2010年1月1日至2016年12月31日在一家三级儿科教学中心接受全甲状腺切除或甲状腺次全切除的38例18岁以下患者。分析了患者的人口统计学、病理、术后PTH、血清钙和住院时间。
中位年龄为14.3岁（范围4.3 - 18.4岁），女性占84.2%。25例患者患有甲状腺恶性肿瘤，13例为良性病变，包括8例多结节性甲状腺肿患者和5例格雷夫斯病患者。在本系列中，63.2%（24/38）的患者术后发生低钙血症（血清钙<8.5mg/dL）。低钙血症组的中位PTH为15.8pg/mL，显著低于血钙正常组的中位PTH 41.6pg/mL（p<0.001）。使用PTH阈值26pg/mL预测低钙血症，敏感性为75%，特异性为100%。6例血钙<7.5mg/dL的患者接受了特立帕肽注射，以避免静脉补钙。血钙正常患者的住院时间为1.7±0.8天，而低钙血症患者为2.9±1.4天（p = 0.002）。我们发现低钙血症的发生率与手术的病理指征之间没有相关性。与全甲状腺切除术相比，甲状腺次全切除术发生低钙血症的风险较低（p = 0.01），而颈部淋巴结清扫术后发生低钙血症的风险增加（p = 0.04）。
术后PTH水平在使用PTH≤26pg/mL的阈值预测该儿科队列中的低钙血症时具有出色的特异性。PTH>26pg/mL的患者可通过口服补钙并门诊随访避免低钙血症。我们未确定一个可靠的PTH临界值，高于该值儿科患者术后可立即安全出院且无需住院。基于恢复室中正常PTH≥10pg/mL提倡门诊甲状腺切除术的成人指南或路径可能不适用于儿童。
