Parathyroid score can predict the duration of required calcium supplementation after total thyroidectomy

Correlation between visual scores and parathyroid function

This mini review summarizes the controversies regarding routine parathyroid identification reviews publications that assess visual scores to predict parathyroid function after thyroidectomy during the pre-ICG era.

Establishing a predictive model of hypoparathyroidism after total thyroidectomy and central lymph node dissection for postoperative calcium supplementation selectively

Background

The core goal of this article is to find some meaningful risk factors that can affect the postoperative hypoparathyroidism of thyroid cancer, create an effective prediction model on this basis, and use it to selectively implement routine prophylactic calcium supplementation for patients after thyroid carcinoma surgery.

Methods

The clinicopathological characteristics of patients with papillary thyroid carcinoma (PTC) who underwent conventional bilateral total thyroidectomy (TT) + bilateral central lymph node dissection from January 2020 to August 2021 in the Affiliated Hospital of Nantong University were retrospectively analyzed. Firstly, this study analyzed the relationship between postoperative hypocalcemia and hypoparathyroidism. Then, we included many potential risk factors such as gender, age, body mass index (BMI), lateral lymph node dissection (LLND) and so on and also performed univariate and multivariate analysis of the independent risk factors for postoperative hypoparathyroidism in patients, and established a predictive scoring model.

Results

Among the 401 patients with PTC, 50.1% developed postoperative hypoparathyroidism. There was significant difference in serum calcium concentration between normal parathyroid group and hypoparathyroidism group after thyroid carcinoma surgery. BMI <24 kg/m², lateral lymph node dissection, multifocality, and extrathyroidal extension (ETE) were all identified as independent risk factors for postoperative hypoparathyroidism. Based on these independent risk factors, a nine-point risk scoring model was created to firstly assess the postoperative parathyroid function status of patients and then to determine whether routine prophylactic calcium supplementation is needed. Importantly, the area under the curve (AUC) of the risk scoring model is equal to 0.979.

Conclusions

At present, prophylactic calcium supplementation after thyroid carcinoma surgery is a controversial postoperative treatment. It should be selectively implemented for high-risk patients with hypoparathyroidism after surgery. Routine prophylactic calcium supplementation is recommended for PTC patients with a score greater than or equal to 5, although there are no clinical symptoms of postoperative hypocalcemia caused by hypoparathyroidism. However, prophylactic calcium supplementation is not recommended for patients with PTC with a score of less than 5; if the patient develops hypocalcemia at the later stage, therapeutic calcium supplementation can then be implemented.

Late Recovery of Parathyroid Function After Total Thyroidectomy: A Case-Control Study

The clinical characteristics of patients with postoperative hypoparathyroidism who recover parathyroid function more than 12 months after surgery have not been studied. We aimed to evaluate whether the intensity of replacement therapy with calcium and calcitriol is related to the late recovery of parathyroid function. We compared the demographic, surgical, pathological, and analytical features of two groups of patients: cases, i. e., late recovery patients (those who recover parathyroid function>1 year after thyroidectomy, n=40), and controls, i. e., patients with permanent hypoparathyroidism (n=260). Replacement therapy with calcium and calcitriol was evaluated at discharge of surgery, 3-6 months, 12 months, and last visit. No significant differences were found in clinical, surgical, pathological, or analytical characteristics between cases and controls. The proportion of cases who required treatment with calcium plus calcitriol at 12 months was significantly lower than that found in controls (p<0.001). Furthermore, daily calcium and calcitriol doses in controls were significantly higher than those in cases at 3-6 months (p=0.014 and p=0.004, respectively) and at 12 months (p<0.001 and p=0.043, respectively). In several models of logistic regression analysis therapy with calcium and calcitriol at 12 months was negatively related to late recovery of parathyroid function. Although delayed recuperation of parathyroid function after total thyroidectomy is uncommon (13%), follow-up beyond 12 months is necessary in patients with postoperative hypoparathyroidism, especially in those whose needs of treatment with Ca and calcitriol are reducing over time.

In Situ Preservation of Parathyroid Gland With Vasculature for Papillary Thyroid Carcinoma Is Associated With Higher PTH Levels After Total Thyroidectomy

PURPOSE

To evaluate the impact of parathyroid gland vasculature preservation in-situ technique (PGVPIST) on postoperative parathyroid hormone (PTH) and calcium plasma levels in thyroid patients undergoing total thyroidectomy for papillary thyroid carcinoma (PTC).

STUDY DESIGN

Retrospective cohort study.

METHODS

Patients with PTC who underwent total thyroidectomy by either the conventional technique (group 1, January 2019 to January 2020) or PGVPIST (group 2, January 2020 to January 2021) were compared. Postoperative blood calcium levels and PTH levels were assessed in these groups.

RESULTS

Totally 149 patients with consecutive PTC underwent total thyroidectomy, including 60 patients in group 1 and 89 patients in group 2. Postoperative serum calcium levels in group 1 were insignificantly lower than in group 2 at day 1 (2.18 ± 0.02 vs 2.15 ± 0.01 mmol/L) and day 30 (2.27 ± 0.02 vs 2.38 ± 0.11) after surgery. But postoperative serum PTH levels in group 1 were significantly lower than that in group 2 at day 1 (23.68 ± 2.54 vs 31.46 ± 2.11 pg/mL) and day 30 (45.63 ± 3.21 vs 55.65 ± 2.89 pg/mL) after surgery.

CONCLUSION

Parathyroid gland vasculature preservation in-situ technique for PTC is associated with higher PTH level after total thyroidectomy. The parathyroid gland vasculature mostly strongly adheres with adjacent thyroid parenchyma. Therefore, deferred processing of tiny thyroid parenchyma of parathyroid gland vessels is essential to prevent devascularization.

Narrative review of management of thyroid surgery complications

Currently, thyroid surgery is the most common and safe operation worldwide. However, thyroidectomy is still not free from the risks of complications and death due to the anatomical structure and physiological function particularity of the thyroid gland. Postoperative complications affect the life quality and life safety of patients after surgery. The common complications include hypoparathyroidism (HP), recurrent laryngeal nerve (RLN) injury, injury to the external branch of the superior laryngeal nerve (EBSLN), postoperative bleeding (PB), thoracic duct injury, laryngeal edema, tracheospasm, tracheal injury, and esophageal injury. A severe complication, such as dyspnea, asphyxia, or thyroid crisis, might cause the death of the patient. Therefore, every thyroid surgeon's responsibility is to remain alert and aware of the occurrence of various intraoperative and postoperative complications and exercise effective prevention and treatment. This is closely related to the advancement in thyroid disease research, the increase in local anatomy knowledge, the standardization of surgical approaches, the improvement in operating skills, the application of new technologies, and the emphasis on specialty training. In addition, many complications that effect patients are much better tolerated if the patient has appropriate expectations of what the complications are and how to treat them. Open communication between surgeon and patient optimizes the potential negative effects that complications may have on patients' quality of life. This paper discusses the prevention, recognition and therapy of intraoperative and postoperative complications in thyroid surgery.

Development and validation of a new model for predicting hypocalcaemia after total thyroidectomy: the NuGra model

BACKGROUND

Hypocalcaemia is the most frequent complication after total thyroidectomy. Finding a method for its early detection has become a priority. A single-center prospective cohort study was conducted to identify risk factors for postoperative hypocalcaemia, develop an early detection model, and test its validity in a different group of patients.

METHODS

The sample was composed of patients who underwent a total thyroidectomy between May 2012 and September 2015. Demographic, clinical, laboratory, and surgical data were collected. The incidence of hypocalcaemia and permanent hypoparathyroidism was calculated. Bivariate and multivariate analysis identified several independent predictors of hypocalcaemia, which were used to design a predictive model. The validity of the model was subsequently tested in a different cohort. Area under the ROC curve (AUROC) was calculated to determine its predictive power.

RESULTS

The study and validation groups included 352 and 118 patients, respectively. Seventy-three patients developed laboratory-confirmed hypocalcaemia (20.7%), and symptomatic in 43 (12.2%). Multivariate analysis confirmed as independent predictors of hypocalcaemia the higher number of parathyroid glands identified [OR 1.41(0.98, 2.02); p = 0.063] and pre-to-postoperative gradient of parathormone decline [OR 1.06(1.04, 1.08); p < 0.001]. Based on these variables, the NuGra (Number of parathyroid glands identified-Gradient of decline) model was developed for predicting laboratory-confirmed hypocalcaemia. Its predictive power was high (AUROC 0.902, CI 0.857-0.947) for the study and the validation group (AUROC 0.956, CI 0.919-0.993).

CONCLUSIONS

A higher number of parathyroid glands identified and a higher gradient of parathormone decline are risk factors for post-thyroidectomy hypocalcaemia. The NuGra model is useful for early prediction of individual risk for hypocalcaemia.

Nontoxic Multinodular Goitre and Incidental Thyroid Cancer: What Is the Best Surgical Strategy?-A Retrospective Study of 2032 Patients

OBJECTIVES

A discussion with regard to the most optimal surgical procedure in nontoxic multinodular goitre (NTMNG). We assessed and compared three main types of operations in 2032 patients with NTMNG.

METHODS

This is a retrospective study of 2032 patients operated on in one center due to NTMNG. The observation period was 48 to 120 months (mean and SD: 87 ± 20).

RESULTS

The early complications included uni- and bilateral recurrent laryngeal nerve paralysis (URLNP, BRLNP), overt tetany (OT), and postoperative bleeding (POB). We observed after TT, STT, and DO URLNP: 15 (1.73%), 3 (0.64%), and 2 (0.28%), respectively (p < 0.05); BRLNP: 3 (0.34%), 2 (0.43%), and 0 (0.0%), respectively (p = 0.25); OT: 42 (4.84%), 6 (1.29%), and 9 (1.28%), respectively (p < 0.0001); and POB: 11 (1.26%), 4 (0.86%), and 3 (0.42%), respectively (p = 0.209). Persistent complications we observed after TT, STT, and DO are the following: URLNP: 9 (1.03%), 3 (0.64%), and 1 (0.14%), respectively (p = 0.086); BRLNP: 1 (0.11%), 1 (0.21%), and 0 (0.0%), respectively (p = 0.51); and OT: 11 (1.26%), 2 (0.43%), and 2 (0.28%), respectively (p = 0.052). Incidental thyroid cancer (ITC) was recognized after TT, STT, and DO in 18 (2.07%), 21 (4.52%), and 11 (1.56%), respectively (p = 0.039). Recurrent goitre (RG) was observed in 1 (0.11%) after TT, 3 (0.64%) after STT, and 2 (0.28%) after DO (p = 0.234).

CONCLUSIONS

Performing less radical surgery in NTMNG is associated with a significantly lower risk of early and late URLNP and OT. In the case of BRLNP (early and persistent) and POB, no statistically significant differences are seen. The occurrence of ITC is higher following more radical surgeries. Less radical surgery is connected with a higher risk of RG.