Poster Presentation ESA-SRB 2023 in conjunction with ENSA

Incidence and risk factors of transient and permanent post-thyroidectomy hypocalcaemia at a rural referral hospital in Australia. (#245)

Aiden Man Hei Cheung 1 , Aye Thin 2
  1. South Western Sydney Local Health District, Campbelltown, NSW, Australia
  2. Endocrinology, Tamworth Rural Referral Hospital, Tamworth, NSW, Australia

Aims

Transient (<12 months) and permanent (>12 months) post-thyroidectomy hypocalcaemia (PTHC) are known complications following thyroidectomies. Their reported incidences vary widely at 19-38% and 0-3% respectively [1]. Different preoperative and postoperative factors have been reported to be associated with PTHC. This study aims to evaluate the incidence and risk factors of PTHC at an Australian centre.

 

Methods

This was a single-centre retrospective cohort study of a rural referral hospital in New South Wales, Australia. 399 cases of total or completion thyroidectomies between 01/06/2012 and 31/05/2022 were identified using electronic medical records. Hypocalcaemia was defined as a corrected serum calcium of <2.10 mmol/L.

 

Results

The incidences of transient and permanent PTHC were 15.3% and 3.3% respectively. PTHC was first detected beyond 24 and 48 hours postoperatively in 8.5% and 2.5% of patients. No patients required readmission for symptomatic hypocalcaemia.

Transient PTHC was associated with preoperative and 24-hour postoperative hypoparathyroidism (p = 0.008 and p <0.001 respectively), and malignant histology (14.3% in benign and 21.3% in malignant, p<0.001). Amongst surgical indications, the incidence of transient PTHC was higher in suspicious thyroid nodules (22.2%), Grave’s disease (20%), and thyroid cancer (18.9%) than multinodular goitre (13.4%) and obstructive goitre (13.2%) (p<0.001).

Hypoparathyroidism 24-hour postoperatively was the only factor associated with permanent PTHC, with the incidences being 8.9%, 0.45% and 0% in hypoparathyroid, euparathyroid and hyperparathyroid patients (p<0.001).

Patients' sex, age, preoperative thyroid status and immediate postoperative parathyroid status were not significantly associated with PTHC.

 

Conclusion

PTHC remains potentially life-threatening complications despite advancement in surgical techniques. No perioperative factors can accurately predict PTHC. Therefore, all post-thyroidectomy patients should undergo routine monitoring for hypocalcaemia for at least 24-48 hours postoperatively.

  1. [1] Edafe, O., Antakia, R., Laskar, N., Uttley, L., & Balasubramanian, S. (2014). Systematic review and meta-analysis of predictors of post-thyroidectomy hypocalcaemia. Journal of British Surgery, 101(4), 307-320.