Clinical protocol using calcium and calcitriol after paediatric total thyroidectomy decreases postoperative hypocalcaemia and inpatient blood tests

Introduction: Postoperative hypocalcaemia is common after thyroidectomy. This study aimed to evaluate whether a standardised post-thyroidectomy protocol using prophylactic calcium and calcitriol reduces hypocalcaemia incidence after total thyroidectomy in children and adolescents. Methods: A cohort children and adolescents <= 18 years of age undergoing total thyroidectomy between January 2016 and October 2022 in one institution were retrospectively identified and divided into pre-protocol and postprotocol groups. The primary outcome measure was hypocalcaemia (total serum calcium of <2.0 mmol/L; ionised serum calcium of 0.9 mmol/L). Secondary outcome measures were the occurrence of hypercalcaemia (serum Calcium >2.7 mmol/L; ionised calcium >1.31 mmol/L), length of hospitalisation and number of postoperative blood tests. Results: There were 22 patients in each group (mean age 11.8; SD 4.3 years, female 36 %). The rate of hypocalcaemia was significantly higher in the pre-protocol group than the post-protocol group (54 % vs 13.6 %, p = 0.010). Patients in the pre-protocol group had more inpatient blood tests (mean 5.4; SD 3.2) than the postprotocol group (mean 3.3; SD 1.8, p = 0.011), although the total postoperative blood test count was similar between the groups. Six (13.6 %) patients developed hypercalcaemia. The rate of hypercalcaemia was similar between groups (pre-protocol 2, 9.1 %; post-protocol 4, 18.1 %; p = 0.664). Length of hospitalisation was similar between groups. Conclusion: Our standardized protocol decreased hypocalcemia and inpatient blood tests after total thyroidectomy in children. Future research should explore if incorporating preoperative calcium and calcitriol treatment, along with intraoperative PTH levels for risk management, can further reduce hypocalcemia rates in paediatric patients.