Preoperative vitamin D deficiency is a risk factor for postoperative hypocalcemia in patients undergoing total thyroidectomy: retrospective cohort study

Significant role of 1,25-dihydroxyvitamin D on serum calcium levels after total thyroidectomy: a prospective cohort study

Introduction

Although active vitamin D (VD) has been used both preoperatively and postoperatively to prevent hypocalcemia risk in patients undergoing total thyroidectomy, the role of 1,25-dihydroxyvitamin D (1,25(OH)2D) has not been examined. This study comprehensively investigated the effects of 1,25(OH)2D on calcium (Ca) concentrations after total thyroidectomy.

Methods

Serum Ca, parathyroid hormone (PTH), and 1,25(OH)2D levels were measured in 82 patients with thyroid disease before and after surgery.

Results

Serum Ca, PTH, and 1,25(OH)2D levels decreased significantly on the morning of the first postoperative day. Notably, the decrease in 1,25(OH)2D concentration was significantly lower than that of PTH concentration (10.5 ± 33.4% vs. 52.1 ± 30.1%, p<0.0001), with 28% of patients showing increases in 1,25(OH)2D. The only factor predicting a postoperative 1,25(OH)2D decrease was a high preoperative 1,25(OH)2D concentration. Postoperative 1,25(OH)2D concentrations, as well as the magnitude and rate of decrease from preoperative levels, showed strong positive correlations with preoperative 1,25(OH)2D concentrations (p<0.0001 for all three variables) but not with PTH concentrations. These findings suggest that 1,25(OH)2D concentrations after thyroidectomy were more strongly dependent on preoperative concentrations than on the effect of PTH decrease and were relatively preserved, possibly preventing sudden severe postoperative hypocalcemia. A high 1,25(OH)2D level was the most important preoperative factor for hypocalcemia (<2 mmol/L; p<0.05) on the first postoperative day; however, only PTH decrease was statistically significant (p<0.001) when intraoperative factors were added. In the PTH >10 pg/mL group, the decrease in 1,25(OH)2D levels was significantly associated with postoperative hypocalcemia (p<0.05). Similarly, in the PTH levels >15 pg/mL group, a decrease in 1,25(OH)2D concentration was a significant factor, and the amount of PTH decrease was no longer significant.

Conclusion

1,25(OH)2D plays an important role in preventing sudden, severe hypocalcemia due to decreased PTH levels after total thyroidectomy, whereas high preoperative 1,25(OH)2D levels are a significant risk factor for postoperative hypocalcemia. Optimizing preoperative protocols to adjust Ca, PTH, and 1,25(OH)2D levels to improve the management of patients undergoing total thyroidectomy and to prevent extreme intraoperative PTH decreases may reduce the risk of hypocalcemia.

A prospective cross-sectional study on hypocalcemia after total thyroidectomy in patients with Graves' disease: insights on secondary hyperparathyroidism

PURPOSE

To investigate the parathyroid function and calcium (Ca) levels in the secondary hyperparathyroidism (SHPT) state in patients with Graves' disease.

METHODS

We examined 31 consecutive patients with Graves' disease without chronic kidney disease, who were treated with total thyroidectomy. The patients were divided into a normal parathyroid hormone (PTH) group (NPTH group; n = 19) with a PTH level ≤ 65 pg/mL, and a secondary hyperparathyroidism group (SHPT group; n = 12), with a PTH level > 65 pg/mL. The PTH and Ca-related parameters were examined and the risk factors for postoperative hypocalcemia were analyzed.

RESULTS

The preoperative Ca level was significantly lower (2.24 ± 0.06 vs. 2.31 ± 0.07 mmol/L, p < 0.05) in the SHPT group than in the NPTH group. The reduction in PTH, 1,25-dihydroxyvitamin D (1,25(OH)2D), and Ca levels from the preoperative day to the next morning was significantly greater in the SHPT group than in the NPTH group (p < 0.05). When intraoperative factors were included, the decrease in the PTH level alone was significant. SHPT was a significant factor in determining the extent of PTH reduction.

CONCLUSIONS

Hyperfunctioning parathyroid glands in the SHPT state were more susceptible to postoperative PTH reduction, which, combined with low preoperative Ca levels, increased the risk of postoperative hypocalcemia in patients with Graves' disease.

Mostaan L, Mohebbi M, Kabiri M, Yaghoubi MA. Preoperative Vitamin.D Status and Post-Total Thyroidectomy Hypocalcemia

Introduction

Hypocalcemia is a common complication of total thyroidectomy (TT). This study was designed to investigate the effect of preoperative vitamin.D (Vit.D) status on the occurrence of post-total thyroidectomy hypocalcemia.

Materials and Methods

Patients who underwent TT without parathyroidectomy were divided into three groups based on their preoperative Serum Vit.D levels (<20 ng/ml, 20-30 ng/ml, and ≥30 ng/ml were considered deficient, insufficient, and normal Vit.D levels, respectively). Serum levels of calcium and phosphorus were measured before and 24 hours after surgery in all patients. The patients were examined for clinical symptoms and signs of hypocalcemia postoperatively. In cases with positive clinical symptoms and signs of hypocalcemia and/or calcium levels <8 mg/dl, PTH level was measured before starting calcium infusion, while serum calcium and phosphorus levels were also measured 24 hours later.

Results

Among 100 patients enrolled in this study, 81% were females. The mean age was 36.60±8.32 years. Before surgery, the mean Vit.D level was 26.9±16.89 ng/ml, while 47% of cases had normal Vit.D level, 32% had insufficient vitamin levels, and 21% had Vit.D deficiency. Twenty-four hours after surgery, the calcium (P=0.356) and phosphorus (P=0.743) levels were not significantly different between the three Vit.D groups. A comparison of postoperative PTH levels between the three Vit.D groups showed no significant difference (P=0.596).

Conclusions

Based on our findings, preoperative serum Vit.D levels did not affect postoperative serum calcium levels.

Factors influencing serum calcium levels and the incidence of hypocalcemia after parathyroidectomy in primary hyperparathyroidism patients

Background

Parathyroidectomy (PTX) is an effective treatment for primary hyperparathyroidism (PHPT) patients. Postoperative hypocalcemia is a common complication after PTX. This study aimed to analyze the factors influencing serum calcium levels and the incidence of hypocalcemia after parathyroidectomy in primary hyperparathyroidism patients.

Methods

The retrospective study included 270 PHPT patients treated with PTX and collected their demographic and clinical information and their laboratory indices. Factors influencing serum calcium levels and hypocalcemia after PTX in PHPT patients were analyzed using univariate and multifactorial analyses.

Results

First, in patients with normal preoperative serum calcium levels (2.20-2.74 mmol/L), the higher the preoperative alkaline phosphatase and serum phosphorus levels, the lower the postoperative serum calcium levels. Furthermore, the higher the preoperative serum calcium levels and the accompanying clinical symptoms, the higher the postoperative serum calcium levels. Low preoperative serum calcium levels were shown to be a risk factor for postoperative hypocalcemia (OR=0.022), and the optimal preoperative serum calcium threshold was 2.625 mmol/L (sensitivity and specificity were 0.587 and 0.712, respectively). Second, in the mild preoperative hypercalcemia group (2.75-3.00 mmol/L), the older the patient, the higher the preoperative and postoperative serum calcium levels, the higher the postoperative serum calcium; the lower the alkaline phosphatase and calcitonin levels, the higher the postoperative serum calcium levels. On the other hand, the younger the patient was, the more likely hypocalcemia blood was (OR=0.947), with an optimal age threshold of 47.5 years (sensitivity and specificity were 0.543 and 0.754, respectively). Third, in the preoperative moderate to severe hypercalcemia group (>3.0mmol/L), patients undergoing a combined contralateral thyroidectomy and a total thyroidectomy had low postoperative serum calcium levels.

Conclusion

Patients with different preoperative serum calcium levels had various factors influencing their postoperative serum calcium levels and postoperative hypocalcemia, which facilitated the assessment of their prognosis.

Incidence of post-surgical hypoparathyroidism (POSH) after total thyroidectomy

Post-surgical hypoparathyroidism (POSH) is a recognised complication of total thyroidectomy, leading to hypocalcaemia and its associated adverse effects. This retrospective study aimed to determine the incidence of POSH and identify perioperative predictors for its development. Data from patients who underwent total or completion thyroidectomy between January 2017 and July 2022 were retrospectively analysed. The incidence of POSH was assessed, and patients were categorised into transient or prolonged POSH at six months postoperatively. Potential predictors for POSH were investigated including gender, histological diagnosis, and preoperative thyroid function. A total of 133 adult patients were included in the study. The incidence of patients recovering from transient POSH within six months was 15%, and 5% had prolonged POSH beyond six months of surgery. Parathyroid hormone (PTH) levels normalised in 83% of prolonged POSH patients within 14-33 months, reducing the incidence of persistent POSH to 0.75%. Despite normal PTH levels, overall, 3% had persistent marginally low calcium levels (mean 2.11 mmol/L) in keeping with relative parathyroid insufficiency. Histological diagnosis of malignancy was the only significant risk factor for both transient and prolonged POSH (RR 2.95, CI 1.54 to 5.67, p = 0.001) in this cohort. Cautious capsular dissection during thyroidectomy and protection of the parathyroid glands and vascular supply produce a low incidence of POSH. Although the vast majority of patients with POSH recover after six months, hypocalcaemia may persist due to relative parathyroid insufficiency, requiring long-term calcium supplementation. Further research is needed to determine the best strategies for preventing and treating this condition.

Preoperative vitamin D level is significantly associated with hypocalcemia after total thyroidectomy

BACKGROUND

To evaluate the association of preoperative vitamin D levels with postoperative hypocalcaemia after total thyroidectomy.

METHODS

The medical records of patients who underwent total thyroidectomy between May 2020 and January 2022 and who had a documented preoperative serum 25-hydroxyvitamin D (25-OHD) concentration were retrospectively reviewed. Vitamin D levels were categorized into four groups: <10 ng/mL (severe vitamin D deficiency), 10-20 ng/mL (vitamin D deficiency), 20-30 ng/mL (vitamin D insufficiency), and > 30 ng/mL (vitamin D sufficiency). Multivariate logistic regression was performed to analyse the association of vitamin D levels with the risk of hypocalcaemia after controlling for potential confounding factors.

RESULTS

A total of 196 patients were included in this study. Of these, 47 (24.0%) had preoperative 25-OHD < 10 ng/mL, 62 (31.6%) had 25-OHD of 10-20 ng/mL, 51 (26.0%) had 25-OHD of 20-30 ng/mL and the remaining 36 (18.4%) had 25-OHD > 30 ng/mL. The incidence of postoperative hypocalcemia was highest in the group of patients with severe vitamin D deficiency (42.6% and 23.4% for postoperative laboratory and symptomatic hypocalcaemia, respectively), followed by the group with vitamin D deficiency (29.0% and 16.1%), the group with vitamin D insufficiency (19.6% and 5.9%) and the group with vitamin D sufficiency (5.6% and 2.8%). Multivariate logistic regression indicated that the odds of postoperative laboratory hypocalcaemia for patients with severe vitamin D deficiency and vitamin D deficiency were 13.20 times (95% CI: 2.69-64.79, P < 0.01) and 6.32 times (95% CI: 1.32-30.28, P = 0.02) greater than for those with vitamin D sufficiency, respectively; while the odds of symptomatic hypocalcaemia for patients with severe vitamin D deficiency was 10.18 times (95% CI: 1.14-90.86, P = 0.04) greater than for those with vitamin D sufficiency.

CONCLUSION

Preoperative vitamin D deficiency (< 20 ng/mL), especially severe vitamin D deficiency (< 10 ng/mL), is an independent predictive factor of postoperative hypocalcaemia after total thyroidectomy.

Adverse events in thyroid surgery: observational study in three surgical units with high volume/year

Background

Thyroid surgery, performed for benign or malignant pathologies, is one of the most frequently performed procedures and its frequency has even been increasing in recent years. Postoperative bleeding, recurrent laryngeal nerve (RLN) palsy, associated to dysphonia, dysphagia, dyspnea, and hypoparathyroidism represent the most fearful and common complications. We conducted a multicenter, observational study of retrospectively collected data in three high-volume referral centers, enrolling all patients undergone to thyroid surgery between January 2016 and December 2017 in Parma University Hospital, Cagliari University Hospital and Ferrara University Hospital.

Materials

Patients were divided into five groups, differentiated thyroid carcinoma, medullary thyroid carcinoma, non-toxic benign pathology, hyperfunctioning benign pathology and NIFTP (Non-invasive Follicular Thyroid neoplasm with Papillary-like nuclear features). A follow up at 7 and 30 days was executed, evaluating the onset of paresthesia, dysphonia and dysphagia. A 6-month follow-up was conducted in cases of early complications.

Results

Totally, 1252 patients were eligible for the study: 907 female and 345 male, with a female to male ratio of 2.6:1 and an average age of 53.428. Total thyroidectomy was performed in 1022 cases, lobectomy in 230. After 6 months we recorded paresthesia in 0.5%, dysphonia in 1.8% and dysphagia in 0.5%.

Conclusion

Our study confirms once again that a share of morbidity escapes the possibilities of prediction and control by the operator, depending on patient anamnestic, pathological or anatomical factors.

[Review of clinical practice guidelines for hypoparathyroidism]

Hypoparathyroidism is a rare disorder characterized by the absent or inappropriately decreased serum parathyroid hormone in the parathyroid glands, which is accompanied by impaired calcium-phosphorus metabolism.The main etiology of hypoparathyroidism remains damage or removal of the parathyroid glands during neck surgery. In view of the incidence of thyroid cancer, primary hyperparathyroidism and other pathologies of the neck organs, which radical treatment can lead to the parathyroid gland impairment, an increased number of patients with hypoparathyroidism is expected. Autoimmune hypoparathyroidism is the second most common form of the disease, usually occurring as part of type 1 autoimmune polyglandular syndrome. Autoimmune hypoparathyroidism usually occurs in childhood and is characterized by a severe course of the disease, especially in the case of concomitant malabsorption syndrome.Chronic hypoparathyroidism of any etiology requires lifelong multicomponent therapy, as well as careful monitoring and an individual approach to choose the optimal treatment strategy. In the absence of adequate follow-up, the risks of long-term complications significantly increase, particularly in the renal, cardiovascular systems; in the soft tissues and in the brain, it could lead to visual disturbances; pathology of the musculoskeletal system with a decreased bone remodeling and a potential risk of fractures, as well as to the neurocognitive disorders and an impaired health-related quality of life.Timely diagnosis, rational medical therapy and management strategy may reduce the risks of short-term and long-term complications, frequency of hospitalizations and disability of patients, as well as improve the prognosis.This review covers the main issues of Russian guidelines for the management of chronic hypoparathyroidism, approved in 2021, including laboratory and instrumental evaluation, treatment approaches and follow-up. This guidelines also include the recommendations for special groups of patients: with acute hypocalcemia, hypoparathyroidism during pregnancy.

Risk factors for postoperative hypocalcaemia after thyroidectomy: A systematic review and meta-analysis

Objective

A meta-analysis to investigate the risk factors for postoperative hypocalcaemia after thyroidectomy in adult patients.

Methods

A systematic search of publications in the electronic databases (PubMed®, The Cochrane Library, Web of Science, OVID and Embase®) from inception to June 2020 was conducted. Screening of titles, abstracts and full texts and data extraction were independently performed by two authors. The OR was selected as the pooled estimate.

Results

The analysis included 23 studies. Twelve significant risk factors for postoperative hypocalcaemia were identified: hypoparathyroidism, OR 5.58; total thyroidectomy, OR 3.59; hypomagnesaemia, OR 2.85; preoperative vitamin D deficiency, OR 2.32; female sex, OR 1.49; thyroid malignancy, OR 1.85; thyroiditis, OR 1.48; substernal multinodular goitres, OR 1.70; parathyroidectomy, OR 1.58; central compartment neck dissection, OR 1.17; modified radical neck dissection, OR 1.57; and central neck dissection, OR 1.54.

Conclusions

This meta-analysis provides moderate-to-high quality evidence that the 12 risk factors were predictive of postoperative hypocalcaemia, which should be monitored closely before thyroidectomy.

Preoperative vitamin D deficiency is associated with increased risk of postoperative hypocalcemia after total thyroidectomy

Prior single-institution studies suggest that preoperative vitamin D deficiency (VDD) is associated with postoperative hypocalcemia and a prolonged length of hospital stay following total thyroidectomy. In this study, we employ a multi-institutional, de-identified electronic health records database to address this issue. We hypothesize that total thyroidectomy patients with preoperative VDD will be at an increased associated risk of postoperative hypocalcemia and hospitalization. Using Cerner Health Facts, we identified 2447 patients who underwent total or subtotal thyroidectomy between 2008 and 2016 and who had a documented 25-hydroxyvitamin D concentration obtained within 12 months of the surgery date using International Classification of Diseases 9/10, Current Procedural Terminology and Healthcare Common Procedure Coding System codes. Data from 984 patients who underwent total thyroidectomy were analyzed. Analysis of variance models estimated the effect of VDD on postoperative numerical variables. Multiple logistic regression estimated the risk of postoperative hypocalcemia and hospital stay, adjusting for any imbalanced demographic variables and operative characteristics. On average, postoperative total calcium concentrations in the VDD group were lower by 0.3 mg/dL compared with that of the non-VDD group (p<0.01). The risk of postoperative hypocalcemia was 2.2 times higher in the VDD group compared with the non-VDD group (p<0.01). Although the length of hospital stay after thyroidectomy was longer in the VDD group compared with the non-VDD group (p=0.03), VDD is not an independent risk factor for prolonged hospitalization following thyroidectomy (p=0.13). VDD is associated with a higher risk of hypocalcemia following total thyroidectomy. Prethyroidectomy operative screening for VDD should be considered.

Preoperative Vitamin D Deficiency is a Risk Factor for Postthyroidectomy Hypoparathyroidism: A Systematic Review and Meta-Analysis of Observational Studies

CONTEXT

Whether preoperative vitamin D deficiency (VDD) contributes to postoperative hypoparathyroidism (hypoPT) risk is unknown.

OBJECTIVE

This work aimed to meta-analyze the best available evidence regarding the association between preoperative vitamin D status and hypoPT risk.

METHODS

A comprehensive literature search was conducted in PubMed, CENTRAL, and Scopus databases, up to October 31, 2020. Study selection included patients undergoing thyroidectomy with preoperative vitamin D status and postoperative hypoPT data. Two researchers independently extracted data from eligible studies. Data were expressed as risk ratio (RR) with 95% CI. The I2 index was employed for heterogeneity.

RESULTS

Thirty-nine studies were included in the quantitative analysis (61 915 cases with transient and 5712 with permanent hypoPT). Patients with VDD demonstrated a higher risk for transient hypoPT compared with those with preoperative vitamin D sufficiency (RR 1.92, 95% CI, 1.50-2.45, I2 = 85%). These results remained significant for patients with preoperative 25-hydroxyvitamin D concentrations less than or equal to 20 ng/mL (mild VDD; RR 1.46, 95% CI, 1.10-1.94, I2 = 88%) and less than or equal to 10 ng/mL (severe VDD; RR 1.98, 95% CI 1.42-2.76, I2 = 85%). The risk of permanent hypoPT was increased only in cases with severe VDD (RR 2.45, 95% CI, 1.30-4.63, I2 = 45%). No difference was evident in subgroup analysis according to study design or quality.

CONCLUSION

Patients with preoperative VDD are at increased risk of transient hypoPT following thyroidectomy. The risk for permanent hypoPT is increased only for those with severe VDD.

A Prospective Study of Vitamin D Supplement in Thyroidectomy Patients Based on Relative Decline of Parathyroid Hormone

Background: In postthyroidectomy patients, hypocalcemia is the most common complication to prolong hospital stay and decrease patients’ satisfaction. Based on current evidence, it is recommended to supply vitamin D to patients with high risk of developing hypocalcemia. However, how to stratify the risk of patients remains challenging.

Aim: We conducted a prospective study to evaluate the effect of vitamin D supplement (calcitriol) on high-risk hypocalcemia patients based on relative decline of parathyroid hormone (RDP).

Method: RDP was calculated by the difference between preoperative and postoperative first-day PTH divided by preoperative PTH and presented as percentage. Patients who underwent total thyroidectomy in addition to bilateral central compartment dissection were enrolled prospectively and were divided into two cohorts: Cohort I: patients with RDP ≤70% and Cohort II: patients with RDP >70%. Patients in Cohort I were then randomly assigned to Group A or B, and patients in Cohort II were randomly assigned to Group C or D. All groups received oral calcium, and patients in Groups B and D also received calcitriol. All patients were followed for one year. In the study, standard procedure dictates that only oral calcium is given to patients whose RDP ≤70% and that oral calcium and calcitriol are given to patients whose RDP >70%. Therefore, Cohort I Group A and Cohort II Group D are controls in this study.

Results: The incidence of clinical hypocalcemia in Groups A and D (the controls) was 11.0% (10/91), and 17.6% (16/91) required additional intravenous calcium. Of note, no patients developed permanent hypocalcemia. Furthermore, calcitriol supplement did not have significant impact on clinical outcomes between Group A and B in Cohort I. By contrast, calcitriol supplement distinctly improved clinical outcome by comparing Groups C and D (Cohort II), as marked by clinical hypocalcemia, need of requiring intravenous calcium, and long-termed decreased levels of PTH.

Conclusion: Supplying calcitriol based on RDP cutoff of 70% may be a wise practice in thyroidectomy patients, and RDP 70% may be a useful predictor to stratify high-risk patients.

Vitamin D Insufficiency Predicts Susceptibility of Parathyroid Hormone Reduction after Total Thyroidectomy in Thyroid Cancer Patients

OBJECTIVE

Given its role in the regulation of calcium and PTH levels, vitamin D was presumed as a potential predictor of postoperative hypoparathyroidism. However, the reports about their association were controversial. This study aims to reveal the relationship between preoperative vitamin D and postoperative parathyroid hormone (PTH).

METHODS

A total of 242 papillary thyroid cancer (PTC) patients who underwent total thyroidectomy (TT) during the period from June 2016 to December 2017 at our hospital were enrolled. Patients were divided into two groups, HypoP and Non-HypoP groups, based on postoperative PTH < 15.0 or ≥15.0 pg/mL, and ΔPTH₅₀+ and ΔPTH₅₀- groups, based on postoperative PTH reduction ratio ≥ 50% or <50%. Clinicopathological features and laboratory data were compared between two sets of groups.

RESULTS

Preoperative PTH level was lower in the HypoP group than in the Non-HypoP group (42.83 vs. 47.52 pg/mL, p=0.018). No significant difference of vitamin D insufficiency was found between the HypoP and Non-HypoP groups (80.8% vs. 74.1%, p=0.226). The rate of vitamin D insufficiency was higher in the ΔPTH₅₀+ group than in the ΔPTH₅₀- group (82.6% vs. 68.4%, p=0.010). By multivariate logistic regression analysis, vitamin D insufficiency was an independent predictor of postoperative PTH reduction ratio ≥ 50% (OR = 2.2, p=0.017).

CONCLUSION

Vitamin D insufficiency is not associated with postoperative PTH in PTC patients undergoing TT. However, vitamin D insufficiency is an independent predictor of postoperative PTH reduction ratio.

Risk Factors for Severe Hypocalcemia in Patients with Secondary Hyperparathyroidism after Total Parathyroidectomy

BACKGROUND

Hypocalcemia is the most common complication of total parathyroidectomy in secondary hyperparathyroidism (SHPT) and is associated with adverse consequences such as spasms, epilepsy, and arrhythmia and even death if the serum calcium level decreases rapidly. Previous studies have identified several risk factors for postoperative severe hypocalcemia (SH) in patients with SHPT, but the sample sizes were small and thus the results may not be reliable.

OBJECTIVES

This study was performed to investigate the risk factors for SH after total parathyroidectomy without autotransplantation (tPTX) in a large sample of patients with uremic hyperparathyroidism.

METHODS

We retrospectively investigated the records of 1,095 patients with SHPT treated with tPTX between January 2008 and December 2018. Based on the postoperative serum calcium concentration, the patients were grouped into SH and non-SH groups. The clinical characteristics and biochemical results were analyzed, and binary logistic regression analysis was used to identify the risk factors for SH.

RESULTS

After surgery, 25.9% of the patients developed SH. Age, diastolic blood pressure (DBP), heart rate, frequency of bone pain, weight of resected glands, preoperative serum calcium, intact parathyroid hormone (iPTH), alkaline phosphatase (ALP), and hemoglobin levels differed between the two groups. Binary logistic regression analyses identified preoperative serum calcium, iPTH, and ALP levels as independent predictors of SH after surgery.

CONCLUSIONS

The preoperative serum calcium, iPTH, and ALP levels can be used to assess the risk of postoperative SH in patients with SHPT. Such patients should thus be monitored closely in order to initiate prompt interventions to avoid SH.

Hypocalcemia After Completion Thyroidectomy for Papillary Thyroid Carcinoma

Surgical management of papillary thyroid carcinoma (PTC) includes total thyroidectomy and lobectomy. After lobectomy, a reoperation called completion thyroidectomy is occasionally required. Postoperative hypocalcemia is the most common complication associated with thyroid surgery. Our main goal was to determine if there is a significant difference between the incidence rate of postoperative hypocalcemia in patients who underwent total thyroidectomy for PTC compared with patients who underwent completion thyroidectomy for PTC. Apart from that, we analyzed the following potential predictive factors for the occurrence of hypocalcemia: sex, age, size of tumor, side of tumor, maximum diameter of individual lobe, occult metastasis, and operating surgeon. The study involved 340 patients who underwent surgery for PTC at the Department of ENT and Head and Neck Surgery, Zagreb University Hospital Centre, between February 25, 2013 and January 3, 2016. Postoperative hypocalcemia incidence rates were higher in the total thyroidectomy group than in the completion thyroidectomy group (37.8% and 29.0%, respectively). However, these differences were not statistically significant. Every analyzed potential predictive factor was proven not to have any correlation with postoperative hypocalcemia. This study demonstrated that there was no significant difference between postoperative hypocalcemia rates in patients who underwent completion thyroidectomy compared with patients who underwent total thyroidectomy for PTC.