Postoperative hypocalcemia after thyroidectomy for Graves' disease

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.

Complications related to thyroidectomy among patients with hyperthyroidism: Exploring the potential for ambulatory surgery

BACKGROUND

Total thyroidectomy for hyperthyroidism is typically followed by overnight admission to monitor for complications including thyrotoxicosis. Outpatient thyroid surgery is increasingly common, but its safety in patients with hyperthyroidism has not been well studied.

METHODS

This retrospective study reviewed 183 patients with hyperthyroidism who underwent total thyroidectomy from 2015 to 2022 at one urban, academic center. The main outcomes were rates of thyroid storm, surgical complications, and 30-day ED visits and readmissions.

RESULTS

Among 183 patients with hyperthyroidism (mean age, 45 ± 14.5 years; 82.5% female), there were no cases of thyroid storm and complications included recurrent laryngeal nerve (RLN) palsy (7.0%), symptomatic hypocalcemia (4.4%), and hematoma (1.6%). ED visits were present in 1.1% and no patients were readmitted.

CONCLUSION

Total thyroidectomy was not associated with thyroid storm and <6% of patients required inpatient management. Ambulatory total thyroidectomy for hyperthyroidism warrants further consideration through identification of predictive factors for postoperative complications.

Development of a tool to calculate the probability of hypocalcemia after total thyroidectomy: a prospective study

PURPOSE

This study aimed to evaluate the ability of the percentage of decrease in serum PTH level in the first 8 h after total thyroidectomy (TT) to predict hypocalcemia requiring Ca supplementation and develop a tool to predict it.

METHODS

97 patients who underwent TT with measurement of preoperative parathyroid hormone (PTH) levels were prospectively evaluated 1 and 8 h after TT; postoperative magnesium (Mg2PO) and phosphorus levels were evaluated on the 2nd day after surgery. The percentage of decrease in PTH level 1 h (%dPTH1h) and 8 h (%dPTH8h) postoperatively and predictors of hypocalcemia requiring Ca supplementation were evaluated and an equation was developed to predict this outcome.

RESULTS

%dPTH1h (p = 0.002), %dPTH8h (p = 0.001) and (Mg2PO) (p < 0.01) were isolated predictors of postoperative hypocalcemia requiring Ca supplementation. The data obtained led to the development of two tools to predict this complication.

CONCLUSIONS

The percentage of decrease in PTH level 1 h and 8 h postoperatively and the magnesium level on the 2nd day after surgery were predictors of more severe hypocalcemia, and an auxiliary tool for predicting this complication was developed.

Risk factors for postoperative hypocalcemia following total thyroidectomy: a retrospective study

BACKGROUND

and Objectives: Hypocalcemia is a commonly reported complication after thyroid surgery. Many possible risk factors have been identified. The purpose of this study is to analyze various risk factors possibly associated with development of postoperative hypocalcemia after thyroid surgery by dividing the sample population into postoperative hypocalcemia and normal calcium groups.

DESIGN

Retrospective.

SETTING

Multiple centers in the Makkah region of Saudi Arabia.

PATIENTS AND METHODS

Risk factors for postoperative hypocalcemia that were obtained for analysis include patient factors, perioperative blood parameters factors, disease-related factors, and surgical factors. Postoperative hypocalcemia was defined as a reduction of the total calcium level to <8.0 mg/dL. Hypocalcemic and normocalcemic patients were compared by multivariate logistic regression.

MAIN OUTCOME MEASURES

Distinguish independent risk factors for postoperative hypocalcemia after thyroidectomy.

SAMPLE SIZE

215 patients.

RESULTS

The incidence of hypocalcemia was 52.1% (112 of 215 patients). According to multivariate analysis, statistically significant risk factors for predicting postoperative hypocalcemia included postoperative parathyroid hormone level <10 pg/dL, inadvertent parathyroid gland resection, and neck dissection surgeries.

CONCLUSION

The causes of postoperative hypocalcemia are multi-factorial. Because many of these factors are modifiable, they should be identified postoperatively to distinguish high-risk groups and implement early preventive measures.

LIMITATIONS

Retrospective with a relatively small size. We encourage additional prospective studies with a larger sample size in multiple regions of the country, which might reveal further significant results.

Comparison of Perioperative Outcomes in Patients with Graves' Disease Undergoing Total Thyroidectomy With or Without Near Infrared Autofluorescence Imaging

Background: The impact of near-infrared autofluorescence (NIRAF) imaging on postthyroidectomy hypocalcemia is controversial. As patients with Graves' disease are at increased risk, our aim was to compare postoperative parathyroid function in these patients undergoing total thyroidectomy (TT) with or without NIRAF imaging. Methods: This was a retrospective "before and after" study, comparing outcomes of patients who underwent TT without or with NIRAF imaging at a single center. Primary outcome was the incidence of temporary hypocalcemia and secondary outcomes, rates of incidental parathyroidectomy on final specimens and permanent hypocalcemia. Analyses were performed using Mann-Whitney U and chi-Square tests. Continuous data are expressed as median (interquartile range). Results: There were 85 patients in NIRAF and 100 patients in non-NIRAF group. Groups were comparable regarding age, gender, body-mass index, and thyroid weight. Number of parathyroid glands identified intraoperatively was 3 in both groups (p = 0.47). Intraoperative parathyroid implantation rate was 16.5% in NIRAF and 6% in non-NIRAF group (p = 0.02). Incidental parathyroidectomy rate on final pathology was 12.9% in NIRAF and 32% in non-NIRAF group (p = 0.002). The rates of temporary (11.7% vs. 16%) and permanent hypocalcemia (2.4% vs. 2%) were similar between the two groups, respectively (p = 0.66). Conclusion: To our knowledge, this is the first comparative study investigating the impact of NIRAF on postoperative parathyroid function after thyroidectomy for Graves' disease. The rate of incidental parathyroidectomy on final pathology was lower with use of NIRAF, without an impact on temporary or permanent hypocalcemia rates compared to conventional technique.

Incidental Parathyroidectomy Among Pediatric Patients Undergoing Thyroid Surgery

OBJECTIVE

To evaluate rates of incidental parathyroidectomy(IP) and to determine risk factors among children undergoing thyroid surgery.

STUDY DESIGN

Retrospective case-control study.

METHODS

Pediatric patients undergoing thyroidectomy with or without neck dissection were included in this retrospective cohort study over a 20 year period. Demographics, clinical features, and surgical outcomes were evaluated. The primary outcome was the presence of parathyroid tissue in the surgical specimen.

RESULTS

Two hundred and eighty-six patients were included (100 cases with ≥1 parathyroid gland found in the pathology specimen and 186 controls). The most common surgical indication was cancer (49%), followed by benign nodule (25%). Hemithyroidectomy was performed in 119 (42%) patients, total thyroidectomy in 138 (48%), and completion in 29 (10%). Central neck dissection (CND) and lateral neck dissection were performed in 41% and 13%, respectively. 27 (9%) patients had parathyroid reimplantation. On univariable analysis, diagnosis, adenopathy on preoperative ultrasound, extent of thyroidectomy, neck dissection, and parathyroid reimplantation were significant predictors of IP. On multivariate analysis, CND > 5 nodes were the sole predictor of IP. Patients with IP were more likely to require postoperative calcium/vitamin D supplementation compared to those without (44% vs. 16%; P < .001).

CONCLUSIONS

Incidental parathyroidectomy during pediatric thyroidectomy is relatively common. CND was independently predictive of IP. There were increased rates of postoperative hypocalcemia when 1 or more parathyroid gland was identified in the specimen. Reimplantation of 1 parathyroid gland was predictive of another gland in the specimen. Anticipating outcomes may help optimize patient care by allowing for early supplementation, frequent monitoring, and consideration of ancillary monitoring modalities in high-risk procedures.

LEVEL OF EVIDENCE

Level 4 Laryngoscope, 132:2262-2269, 2022.

Revisiting the role of surgery in the treatment of Graves' disease

Graves' disease (GD) can be managed by antithyroid drugs (ATD), radioactive iodine (RAI) and surgery. Thyroidectomy offers the highest success rates for both primary and persistent disease, yet it is the least recommended or utilized option reaching <1% for primary disease and <25% for persistent disease. Several surveys have found surgery to be the least recommended by endocrinologists worldwide. With the development of remote access thyroidectomies and intraoperative nerve monitoring of the recurrent laryngeal nerve, combined with current knowledge of possible risks associated with RAI or failure of ATDs, revaluation of the benefit to harm ratio of surgery in the treatment of GD is warranted. The aim of this review is to discuss possible reasons for the low proportion of surgery in the treatment of GD, emphasizing an evidence-based approach to the clinicians' preferences for surgical referrals, surgical indications and confronting traditional reasons and concerns relating to the low referral rate with up-to-date data.

Transient Hypocalcemia After Total Thyroidectomy: The Obesity Paradox at Work?

INTRODUCTION

With increasing rates of obesity worldwide, a correlation between high body mass index (BMI) and postoperative morbidity after thyroid surgery remains unclear. Postoperative transient hypocalcemia is common after total thyroidectomy due to interruption of parathyroid function. This study examines the relationship between BMI and hypocalcemia after total thyroidectomy.

MATERIALS AND METHODS

A retrospective review of prospectively collected data for 1135 patients who underwent total thyroidectomy for cancer, multinodular goiter (MNG), or Graves' disease between June 2009 and November 2020 at a single institution was performed. BMI groups followed the World Health Organization classification. Hypocalcemia was defined as serum calcium ≤8 mg/dL. Calcium levels measured on postoperative day 0 and the following morning were compared between the BMI groups.

RESULTS

Of 1135 total thyroidectomy patients, 85% were women. The mean age and standard deviation of patients was 49 (± 13) y, with most of Hispanic origin (64%). Overall, 41.5% of patients had cancer, 45% nontoxic MNG, 5.8% toxic MNG, and 12% Graves' disease. Stratified by BMI, 27% of patients were normal, 34% overweight, and 39% obese. Overall, overweight and obese patients experienced less transient hypocalcemia at both time points compared to normal patients postoperatively (P = 0.01 and P = 0.009). Furthermore, overweight and obese patients with Graves' disease experienced less transient hypocalcemia at both time points (P = 0.04 and P = 0.05). There was no statistical difference in other groups.

CONCLUSIONS

A protective role of higher BMI or "obesity paradox" for postoperative hypocalcemia may exist in those obese patients after total thyroidectomy.

Seasonal variation in calcium treatment after thyroidectomy as surrogate for post-operative hypocalcemia: a retrospective register-based national cohort study

Background

Hypocalcemia is one of the most common complications of thyroidectomy, and vitamin D deficiency has been found to be an independent risk factor. Sweden is located north of the 55th latitude, resulting in a significant seasonal variation in sun exposure, thereby large variation in the naturally occurring levels of vitamin D. This study aimed to determine if there is a correlation between season of surgery and post-thyroidectomy hypocalcemia.

Methods

We conducted a retrospective register-based observation study on patients who had undergone total thyroidectomy during 2008–2015. In total, 7125 patients operated in Swedish facilities were identified via the Scandinavian Quality Register for Thyroid, Parathyroid, and Adrenal Surgery (SQRTPA). Patients operated during February–April were included in the dark group and patients operated during August–October were included in the bright group. Further stratification was made on the indication for surgery. The primary outcome was post-operative calcium treatment due to hypocalcemia, defined as having received calcium orally or intravenously before discharge.

Results

The risk of receiving post-operative calcium treatment was significantly lower in the bright group (29.7%) compared to the dark group (35.1%), with a relative risk of 0.846 (P < 0.001). This correlation held true if the indication for surgery was goiter or thyrotoxicosis. For malignancy, there was no significant difference between the groups.

Conclusion

In this cohort, total thyroidectomy performed during August–October was associated with a lower rate of calcium treatment given post-operatively when compared to total thyroidectomy performed during February–April. This would indicate a decreased risk of post-operative hypocalcemia if surgery was carried out after the brighter season.

The Influence of Prophylactic Calcium and Magnesium Supplementation on Postoperative Quality of Life and Hypocalcemia After Total Thyroidectomy: Study Protocol for a Randomized Controlled Trial

Background: We want to investigate if a routine preoperative dietary supplementation of calcium and magnesium prior to thyroidectomy for nodular goiter and graves' disease can influence patients' outcome with regards to hypocalcemia associated symptoms and quality of life in order to reduce the risk of post-thyroidectomy hypocalcemia and to improve patient's quality of life.

Methods: The study will be conducted as a two-armed randomized controlled trial including patients scheduled for total thyroidectomy. Patients assigned to the intervention group will receive calcium carbonate and magnesium oxide starting 2 weeks preoperatively. Primary outcome is the postoperative quality of life measured by the ThyPRO-39 and EQ-5D questionnaires. Secondary outcome is the assessment of postoperative biochemical (calcium and PTH levels) and clinical hypocalcemia (symptoms as reported by the patient).

Discussion: A prophylactic dietary supplementation with calcium and magnesium, which could easily be implemented in the preoperative setting, could potentially help to avoid or reduce hypocalcemia-associated symptoms and improve quality of life. In the event of a positive outcome, this preoperative procedure can be an inexpensive way to prepare patients scheduled for thyroidectomy and can possibly reduce disease-specific costs by reducing the postoperative complication rate.

Clinical Trial Registration: DRKS00017195 in the German clinical trials register (Deutsches Register Klinischer Studien, DRKS) on the 22.05.2019.

Outcomes and Predictors of 30-Day Readmissions for Hyperthyroidism: A Nationwide Study

Hyperthyroidism is associated with an elevated risk of cardiovascular events and worse hospital outcomes. The Nationwide Readmissions Database (NRD) 2018 was used to determine the characteristics of 30-day readmission in patients with hyperthyroidism. The 30-day all-cause readmission rate for hyperthyroidism was 10.3%. About 21.7% had hyperthyroidism as the principal diagnosis on readmission. Readmissions were associated with an increased odds of inpatient mortality (odds ratio, 7.04; 95% confidence interval [CI], 3.97 to 12.49), length of stay (5.2 days vs. 4.0 days; 95% CI, 0.7 to 1.8), total hospital charges, and cost of hospitalizations. Independent predictors of 30-day all-cause readmissions included Charlson Comorbidity Index ≥3 (adjusted hazard ratio [aHR], 1.76; 95% CI, 1.15 to 2.71), discharge against medical advice (aHR, 2.30; 95% CI, 1.50 to 3.53), protein-energy malnutrition (aHR, 1.54; 95% CI, 1.15 to 2.07), and atrial fibrillation (aHR, 1.41; 95% CI, 1.11 to 1.79). Aggressive but appropriate monitoring is warranted in patients with hyperthyroidism to prevent readmissions.

The utility of indocyanine green (ICG) for the identification and assessment of viability of the parathyroid glands during thyroidectomy

We conducted this study to evaluate the ability of indocyanine green (ICG) and near infra-red fluorescence (NIRF) camera to aid in the identification and assessment of viability of parathyroid glands during thyroid surgery. A prospective observational study was conducted between May and October 2020 among 50 consecutive patients who underwent total thyroidectomy at a single institution. Parathyroid glands were identified under white light during thyroidectomy following which reconstituted ICG was injected through a peripheral vein and the location of parathyroid glands was confirmed. The perfusion to the parathyroid gland was assessed by documenting the fluorescence intensity score (FIS) and the parathyroid angiogram score (PAS). There was no difference in the number of parathyroid glands seen on visual inspection 147 (73.5%) when compared to under NIRF camera, 146 (73%). Though the rate of postoperative hypoparathyroidism was lower in the cohort with FIS 3 (14.2%) compared to score 2 and 1 (28.5% and 100%, respectively), this was not significant (p = 0.35). A significant correlation was noted between a delayed flow on PAS and the development of post-thyroidectomy hypoparathyroidism (p = 0.01). PAS had a sensitivity of 100%, specificity of 88.6%, NPV of 100% and PPV of 55.6% to predict the development of post-thyroidectomy hypoparathyroidism. In this study, there was no additional benefit of ICG and NIRF camera in the identification of parathyroid glands. However, ICG angiogram seems to be a good adjunct for the intraoperative assessment of the viability of the parathyroid glands and accurately predicts the development of postoperative hypoparathyroidism.

Hypocalcemia following total and subtotal thyroidectomy and associated factors

BACKGROUND

Thyroidectomy is one of the common endocrinological surgeries for the treatment of thyroid disorders. Hypocalcemia is the potential complication after thyroidectomy, where is persistency can lead to serious systemic effects. The aim of this study is to evaluate the incidence of hypocalcemia in thyroidectomy patients.

METHODS

In this cross-sectional study, patients referred to (XXX) for thyroidectomy from 2019 to 2020 were enrolled. Preoperative serum calcium and postoperative 24- and 48-h calcium levels were evaluated in these patients. Demographic data (sex and gender), calcium levels, type of thyroidectomy and duration of surgery was recorded for all the patients. SPSS v22 was used for statistical analysis. P < 0.05 was considered as statistically significant.

RESULTS

Of 143 patients included in the study, the mean age was 49.7 ± 10.9 years and 61.5% were females and 38.5% were males. 49% patients had hypocalcemia in the first 24 hours after surgery and 63.6% following 48 hours of the surgery. The difference in calcium levels at three intervals were statistically significant, p = 0.001. The incidence of hypocalcemia was significantly more in women at 48 postoperative hours, p = 0.025. The age and duration of surgery was not significantly correlated with hypocalcemia, p > 0.05, whereas, patients who underwent total thyroidectomy had greater incidence of hypocalcemia 24 hours after the surgery, p = 0.021.

CONCLUSIONS

The incidence of hypocalcemia is greater in total thyroidectomy and female patients. Our study did not report significant correlation between duration of the surgery and age of the patients.

Hungry Bone Syndrome Secondary to Subtotal Thyroidectomy in A Patient With Thyrotoxicosis

Patients with thyrotoxicosis are prone to transient hypocalcemia after thyroidectomy, which may be due in part to surgical damage to the parathyroid glands. Hungry bone syndrome (HBS) can also cause hypocalcemia after thyroidectomy. HBS is due to increased osteoblast-mediated bone formation activity and normal or decreased bone resorption activity. As HBS is uncommon in patients after thyroidectomy, we herein present a case of hypocalcemia secondary to HBS after subtotal thyroidectomy for thyrotoxicosis in a 25-year-old woman with a two-month history of tingling extremities and carpopedal spasms after subtotal thyroidectomy for thyrotoxicosis. Diagnostic tests showed hypocalcemia and hyperphosphatemia with elevated parathyroid hormone levels and moderately decreased serum 25-hydroxyvitamin D levels. In addition to thyroid hormone replacement therapy, she was given calcitriol and Caltrate D (600 mg calcium plus 125 IU cholecalciferol). After two months of treatment, she no longer had spasms and her paresthesia improved. Meanwhile, serum electrolytes and parathyroid hormone levels had almost returned to the normal ranges. This is a rare case of HBS presented as a complication of subtotal thyroidectomy in a patient with thyrotoxicosis.

Outcomes After Urgent Thyroidectomy Following Rapid Control of Thyrotoxicosis in Graves' Disease are Similar to Those After Elective Surgery in Well-Controlled Disease

BACKGROUND

Surgery for Graves' disease (GD) is usually performed after adequate control with medical treatment. Occasionally, rapid pre-operative optimization is required. The primary objective was to compare the outcomes of patients undergoing elective surgery for well-controlled GD with those undergoing rapid pre-operative treatment. We also propose a formal treatment protocol for future use.

METHODS

A retrospective cohort study in a tertiary referral centre included 247 patients with well-controlled GD undergoing elective surgery and 19 patients with poorly controlled disease undergoing surgery after rapid optimization. The latter group did not respond well to thionamides (carbimazole and/or propylthiouracil) or had intolerance or side effects to thionamides and were treated with a range of non-thionamide drugs, including Lugol's iodine, cholestyramine, beta blockers and steroids (with or without thionamides), and closely monitored for 1-2 weeks before surgery. Outcome measures included thyroid storm, hypoparathyroidism and recurrent laryngeal nerve palsy.

RESULTS

In total, 266 patients with male-to-female ratio of 1:6 and median (interquartile range) age of 39 (31-51) were included. Overall, long-term recurrent laryngeal palsy and hypoparathyroidism occurred in 1 (0.38%) and 13 (4.9%) patients, respectively. No patient had thyroid storm. There was no significant difference in hypoparathyroidism (p = 1), vocal cord palsy (p = 0.803) and post-operative bleeding (p = 0.362), between elective surgery and rapid optimization groups.

CONCLUSION

Rapid pre-operative treatment is effective, safe and is associated with similar outcomes compared to usual treatment. A rapid pre-operative optimization protocol is proposed.

Volume, outcomes, and quality standards in thyroid surgery: an evidence-based analysis-European Society of Endocrine Surgeons (ESES) positional statement

INTRODUCTION

Continuous efforts in surgical speciality aim to improve outcome. Therefore, correlation of volume and outcome, developing subspecialization, and identification of reliable parameters to identify and measure quality in surgery gain increasing attention in the surgical community as well as in public health care systems, and by health care providers. The need to investigate these correlations in the area of endocrine surgery was identified by ESES, and thyroid surgery was chosen for this analysis of the prevalent literature with regard to outcome and volume.

MATERIALS AND METHODS

A literature search that is detailed below about correlation between volume and outcome in thyroid surgery was performed and assessed from an evidence-based perspective. Following presentation and live data discussion, a revised final positional statement was presented and consented by the ESES assembly.

RESULTS

There is a lack of prospective randomized controlled studies for all items representing quality parameters of thyroid surgery using uniform definitions. Therefore, evidence levels are low and recommendation grades are based mainly on expert and peer evaluation of the prevalent data.

CONCLUSION

In thyroid surgery a volume and outcome relationship exists with respect to the prevalence of complications. Besides volume, cumulative experience is expected to improve outcomes. In accordance with global data, a case load of < 25 thyroidectomies per surgeon per year appears to identify a low-volume surgeon, while > 50 thyroidectomies per surgeon per year identify a high-volume surgeon. A center with a case load of > 100 thyroidectomies per year is considered high-volume. Thyroid cancer and autoimmune thyroid disease predict an increased risk of surgical morbidity and should be operated by high-volume surgeons. Oncological results of thyroid cancer surgery are significantly better when performed by high-volume surgeons.

Influence of gender and women's age on the prevalence of parathyroid failure after total thyroidectomy for multinodular goiter

Background

Female gender, particularly of a young age, has been reported as a risk factor for hypocalcemia after total thyroidectomy. There are no studies, however, addressing specifically the influence of women's age and menstrual status on postoperative parathyroid function.

Methods

Cohort study of consecutive patients undergoing total thyroidectomy for benign goiter between 2000-2017, excluding those with associated hyperparathyroidism, reoperation or conservative procedures. Prevalence of postoperative hypocalcemia (s-Ca <8 mg/dL at 24 hours), protracted (1-month) and permanent hypoparathyroidism (>1 year) were the main variables studied. Complete >1-year follow-up was achieved for all patients developing post-thyroidectomy hypocalcemia. Demographic, disease-related, number of parathyroid glands remaining in situ (PGRIS), biochemical and surgical variables were recorded. The impact of menstrual status on parathyroid function was analyzed by comparing two groups of women using a cut-off age of 45 years.

Results

A total of 811 patients were included: 14 percent were males and 86 percent females with a mean age of 53.2 years. The prevalence of postoperative hypocalcemia was ten points higher in women than in men (23.7% vs. 36.4%; P=0.008). Permanent hypoparathyroidism was more common in women than in men (5% vs. 0.9%; P=0.048). Compared to females ≥45 years, young women presented higher rates of all three parathyroid failure syndromes despite similar PGRIS scores. Age <45 years and low PGRIS scores were the only independent variables predicting postoperative hypocalcemia in females.

Conclusions

Premenopausal patients presented a higher prevalence of parathyroid failure and permanent hypoparathyroidism with similar PGRIS scores suggesting the presence of a sex-hormone factor influencing post-thyroidectomy parathyroid function.

Total thyroidectomy: Safe and curative treatment option for hyperthyroidism

BACKGROUND

While use of total thyroidectomy has increased in management of hyperthyroidism, concerns exist about increased surgical complication rates; most notably, hematoma, recurrent laryngeal nerve (RLN) injury, and hypocalcemia.

METHODS

Retrospective cohort study of 454 patients undergoing total thyroidectomy between 2003 and 2015. All patients had surgery for hyperthyroidism, benign euthyroid disease, or thyroid malignancy.

RESULTS

Total thyroidectomy for hyperthyroidism was not associated with an increased risk for any postoperative complication. Transient hypocalcemia, temporary dysphonia, and postoperative hematoma rates were not significantly different for patients with hyperthyroid (n = 91), euthyroid benign (n = 237), and malignant (n = 126) disease. Permanent hypocalcemia and recurrent laryngeal nerve injury were not noted in any hyperthyroid patients. Complication rates were similar for hyperthyroid patients with Graves' disease vs toxic multinodular goiter.

CONCLUSION

This study affirms safety and efficacy of total thyroidectomy as standard treatment for hyperthyroidism.

Postoperative Hypoparathyroidism: Prognosis, Prevention, and Treatment (Review)

This review summarizes the results of studies concerning the problem of post-surgical hypoparathyroidism, a common complication of thyroid gland surgery, decreasing the quality of life in patients and, in some cases, leading to disability. A search for publications was carried out in electronic databases Web of Science, Scopus, Academic Search Complete (EBSCO), eLIBRARY, using keywords. The search depth was 7-10 years. Prevalence of post-surgical hypoparathyroidism was evaluated, the pathogenetic causes of the disease development, its clinical forms, methods of diagnosis and treatment were studied. It has been found that there is no single algorithm for analyzing the prognostic factors for the development of this pathological condition. It is emphasized that drug therapy of post-surgical hypoparathyroidism has a number of adverse effects. Therefore, the issues of prevention and surgical correction are of particular relevance. However, controversial opinions of contemporary authors about their clinical effectiveness determine the scientific and practical significance of further research on these issues.

Severe Hypocalcemia After Thyroidectomy: An Analysis of 7366 Patients

OBJECTIVE

The aim of the study was to determine severe hypocalcemia rate following thyroidectomy and factors associated with its occurrence.

BACKGROUND

Hypocalcemia is the most common complication after thyroidectomy. Severe post-thyroidectomy hypocalcemia can be life-threatening; data on this specific complication are scarce.

METHODS

Patients who underwent thyroidectomy in the American College of Surgeons-National Surgical Quality Improvement Program thyroidectomy-targeted database (2016-2017) were abstracted. A severe hypocalcemic event was defined as hypocalcemia requiring intravenous calcium, emergent clinic/hospital visit, or a readmission for hypocalcemia. Multivariable regression was used to identify factors independently associated with occurrence of severe hypocalcemia.

RESULTS

Severe hypocalcemia occurred in 5.8% (n = 428) of 7366 thyroidectomy patients, with 83.2% necessitating intravenous calcium treatment. Rate of severe hypocalcemia varied by diagnosis and procedure (0.5% for subtotal thyroidectomy to 12.5% for thyroidectomy involving neck dissections). Overall, 38.3% of severe hypocalcemic events occurred after discharge; in this subset, 59.1% experienced severe hypocalcemia despite being discharged with calcium and vitamin D. Severe hypocalcemia patients had higher rates of recurrent laryngeal nerve injury (13.4% vs 6.6%), unplanned reoperations (4.4% vs 1.3%), and longer hospital stay (30.4% vs 6.2% ≥3 days (all P < 0.01). After multivariate adjustment, severe hypocalcemia was associated with multiple factors including Graves disease [odds ratio (OR) = 2.06], lateral neck dissections (OR: 3.10), and unexpected reoperations (OR = 3.55); all P values less than 0.01.

CONCLUSIONS

Severe hypocalcemia and suboptimal hypocalcemia management after thyroidectomy are common. Patients who experienced severe hypocalcemia had higher rates of nerve injury and unexpected reoperations, indicating surgical complexity and provider inexperience. More biochemical surveillance particularly a parathyroid hormone-based protocol, fine-tuned supplementation, and selective referral could reduce occurrence of this morbid complication.

Correlation between iPTH Levels on the First Postoperative Day After Total Thyroidectomy and Permanent Hypoparathyroidism: Our Experience

Permanent hypoparathyroidism is the most common long-term complication after thyroidectomy. We evaluated whether iPTH concentrations on the first postoperative day may be a good predictor of this complication.

Patients undergoing thyroidectomy in our Unit between January 2017 and February 2018 who developed postsurgical hypoparathyroidism were analysed. According to iPTH values on the first postoperative day and on the basis of the detection threshold of the iPTH test used, patients were divided into 2 groups: Group A (iPTH < 6.3 pg/mL, undetectable), Group B (iPTH ≥ 6.3 pg/mL).

Seventy-five patients were included in this study: 64 in Group A and 11 in Group B. Permanent hypoparathyroidism occurred in 14 (21.88%) patients in Group A, while none developed this complication in Group B. When iPTH was < 6.3 pg/mL, the sensitivity for the prediction of permanent hypoparathyroidism was 100%, the specificity was 18.03%, the positive predictive value was 21.88% and the negative predictive value was 100%.

No patient with iPTH ≥ 6.3 pg/mL on the first postoperative day developed permanent hypoparathyroidism. On the other hand, iPTH concentrations < 6.3 pg/mL have not proved to be a strong predictor of this condition. However, this cut-off value can be useful to identify patients at risk of developing this complication.

Hypocalcemia after Total Thyroidectomy in Graves Disease

CONTEXT

Total thyroidectomy has been shown to provide a cost-effective and efficient method of permanently treating Graves disease; however, hypocalcemia can be a common complication.

OBJECTIVE

To evaluate the risk of hypocalcemia after total thyroidectomy in patients with vs without Graves disease.

DESIGN

The 2016 American College of Surgeons National Surgical Quality Improvement Program participant use data files for procedure-targeted thyroidectomy and from 5871 patients were merged. This study included any patient who underwent total thyroidectomy.

MAIN OUTCOME MEASURES

Whether symptomatic hypocalcemia developed anytime within 30 days after the thyroidectomy. A clinically severe hypocalcemic event was also evaluated as a secondary outcome measure.

RESULTS

Of the 2143 patients who underwent total thyroidectomy, 222 patients experienced hypocalcemia after surgery, 124 of whom had symptomatic hypocalcemia postoperatively. Among patients with hypocalcemia, 16.3% had Graves disease, whereas only 9.4% of patients without Graves disease experienced significant hypocalcemia. Multivariable logistic regression analysis revealed that women (odds ratio = 1.79; 95% confidence interval = 1.16-2.76; p = 0.009) and patients who underwent parathyroid autotransplantation (odds ratio = 1.91; 95% confidence interval = 1.30-2.81; p = 0.001) were at greater risk of development of hypocalcemia. Older patients were less likely to experience hypocalcemia postoperatively (odds ratio = 0.586; 95% confidence interval = 0.44-0.79; p = 0.0001).

CONCLUSION

Patients with Graves disease are about twice as likely to experience hypocalcemia or clinically severe hypocalcemia postoperatively than are patients without the disease.

Considerations for Thyroidectomy as Treatment for Graves Disease

Hyperthyroidism is a clinical state that results from abnormally elevated thyroid hormones. Thyroid gland affects many organ systems; therefore, patients usually present with multiple clinical manifestations that involve many organ systems such as the nervous, cardiovascular, muscular, and endocrine system as well as skin manifestations. Hyperthyroidism is most commonly caused by Graves disease, which is caused by autoantibodies to the thyrotropin receptor (TRAb). Other causes of hyperthyroidism include toxic multinodular goiter, toxic single adenoma, and thyroiditis. Diagnosis of hyperthyroidism can be established by measurement of thyroid-stimulating hormone (TSH), which will be suppressed with either elevated free T4 and/or T3 (overt hyperthyroidism) or normal free T3 and T4 (subclinical hyperthyroidism). Hyperthyroidism can be treated with antithyroid drugs (ATDs), radioactive iodine (RAI), or thyroidectomy. ATDs have a higher replacement rate when compared with RAI or thyroidectomy. Recent evidence has shown that thyroidectomy is a very effective, safe treatment modality for hyperthyroidism and can be performed as an outpatient procedure. This review article provides some of the most recent evidence on diagnosing and treating patients with hyperthyroidism.

Clinical Utility of Intraoperative Parathyroid Hormone Measurement in Children and Adolescents Undergoing Total Thyroidectomy

Background: Hypoparathyroidism is one of the most common complications for patients undergoing total thyroidectomy. Our study's primary objective was to assess if intraoperative PTH levels correlate with parathyroid gland function recovery time in pediatric patients following total thyroidectomy. Methods: Retrospective review of pediatric patients who underwent thyroid surgery at CHOP for demographics and laboratory test values (calcium, phosphorus, and parathyroid hormone). We defined Time of Recovery (TOR) as the time difference from first intra-operative parathyroid hormone level (ioPTH) timepoint until normalization of PTH (> 10 pg/mL) post-thyroidectomy. Calcium and vitamin D supplements were weaned following normalization of calcium and phosphorous levels postoperatively. Patients were excluded if they lacked three intraoperative PTH timepoints or were missing postoperative follow-up PTH data. Results: 65 patients (54 female), median age 15 (range 5-23 years), underwent thyroid surgery and met study inclusion criteria. The correlations of 2nd and 3rd ioPTHs with TOR were statistically significant (p < 0.05): the lower the ioPTH, the greater the recovery time. Stratifying patients into high-risk (2nd ioPTH ≤ 10 pg/mL), moderate-risk (2nd ioPTH between 10 and 20 pg/mL), and low-risk (2nd ioPTH ≥ 20 pg/mL) tertiles, the TOR decreased by orders of magnitudes from an average of 43.13 ± 76.00 to 6.10 ± 17.44 to 1.85 ± 6.20 days. These differences were statistically significant (p < 0.05). Conclusions: Our study results confirm the usefulness of intraoperative PTH levels to predict pediatric patient recovery post-surgery and provides useful anticipatory guidance to optimize timing and frequency of postoperative laboratory surveillance.

Increased risk of postoperative complications after total thyroidectomy with Graves' disease

BACKGROUND

The effect of Graves' disease on the risk of postoperative complications in patients undergoing total thyroidectomy is unclear.

METHODS

The incidence of recurrent laryngeal nerve (RLN) injury and hypoparathyroidism were analyzed between 165 patients with Graves' disease (GD group) and 1:1 matched patients with euthyroid states (control group).

RESULTS

The matched cohorts did not differ in age, sex, body mass index, pathologic diagnosis, and extent of operation. Excised thyroid weight was higher in the Graves' disease than in the control group (60.1 g vs 22.6 g; P < .001). Multivariate analysis showed that Graves' disease significantly increased risks of transient RLN injury (odds ratio [OR] = 4.7, 95% confidence interval [CI] = 1.5-15.5; P = .010) and transient hypoparathyroidism (OR = 2.8, 95% CI = 1.3-5.8; P = .007). Rates of permanent complications were comparable in the Graves' disease and control groups.

CONCLUSIONS

Graves' disease can be a predictive factor for postoperative RLN injury and hypoparathyroidism after total thyroidectomy.

Surgical Hypoparathyroidism

Surgical hypoparathyroidism is the most common cause of hypoparathyroidism and the result of intentional or inadvertent extirpation, trauma, or devascularization of the parathyroid glands. Surgical hypoparathyroidism may present as a medical emergency. Pediatric patients, those with Graves disease, and those undergoing extensive neck dissections or reoperative neck surgery are at particular risk for this complication. Extensive surgical expertise, immediate or delayed autotransplantation, and prophylactic and postoperative calcium/vitamin D supplementation in select patients are associated with a reduction in the risk of surgical hypoparathyroidism. Intraoperative parathyroid imaging is among novel strategies being investigated to mitigate surgical hypoparathyroidism in the intraoperative setting.

Risk factors and outcomes of incidental parathyroidectomy in thyroidectomy: A systematic review and meta-analysis

Introduction

Postoperative hypocalcemia is the most common complication of thyroidectomy. Incidental parathyroidectomy (IP) was thought to be associated with postoperative hypocalcemia. However, according to previous studies, the risk factors and clinical outcomes of IP remain controversial.

Methods

Eligible studies were searched in databases including PubMed, Web of Science, and EMBASE from January 1990 to September 2017. Articles focusing on the relationship between IP and postoperative hypocalcemia were included. The risk of publication bias was assessed using Begg’s test and Egger’s regression asymmetry test. Pooled analysis was performed to evaluate the effect of IP on postoperative hypocalcemia and related risk factors. Sensitivity analysis was also conducted to test the stability of our results. The effects of hypocalcemia type, permanent definition, IP incidence, total thyroidectomy, and malignancy operation were also examined using a further subgroup analysis.

Results

Thirty-five studies were finally included in the analysis after an exhaustive literature review. Pathology data demonstrate that incidental parathyroidectomy occurred in various locations: intrathyroidal (2.2–50.0%), intracapsular (16.7–40.0%) and extracapsular (15.7–81.1%) regions. Overall, the analysis found that malignancy (RR = 1.60, 95% CI: 1.27 to 2.02; p< 0.0001), central neck dissection (RR = 2.35, 95% CI: 1.47 to 3.75; p = 0.0004), total thyroidectomy (RR = 1.42, 95% CI: 1.20 to 1.67; p< 0.0001) and reoperation (RR = 1.81, 95% CI: 1.20 to 2.75; p = 0.005) were significant risk factors of IP in thyroid surgery. There was an obvious effect of IP on temporary/permanent (RR = 1.59, 95% CI: 1.37 to 1.84; p< 0.0001) and permanent (RD = 0.0220, 95% CI: 0.0069 to 0.0370; p = 0.0042) postoperative hypocalcemia. Sensitivity analysis showed that these results were robust. The subgroup analysis found that IP played a significant role in both biochemical and clinical hypocalcemia in thyroidectomy (p < 0.0001 and p = 0.0003, separately). The association of IP and permanent hypocalcemia using different definitions (6 months or more than 12 months) was also confirmed by the analysis. IP increased the incidence of temporary/permanent and permanent hypocalcemia for cases undergoing total thyroidectomy (40.4% vs 24.8% and 5.8% vs 1.4%, respectively). Thyroidectomy with IP was associated with more permanent hypocalcemia (RR = 3.10, 95% CI: 2.01 to 4.78; p< 0.0001) in malignant cases but was not associated with temporary/permanent hypocalcemia.

Conclusions

Malignancy, central neck dissection, total thyroidectomy and reoperation were found to be significant risk factors of IP. IP increases the risk of postoperative hypocalcemia after thyroidectomy. We recommend a more meticulous intraoperative identification of parathyroid gland in thyroidectomy to reduce IP, particularly for total thyroidectomy and malignancy cases.

To admit or not to admit? Experience with outpatient thyroidectomy for Graves' disease in a high-volume tertiary care center

BACKGROUND

Outpatient thyroidectomy is increasingly performed. Thyroidectomy for Graves' disease, however, has greater risk of periprocedural complications, limiting use of same-day procedures. We sought to demonstrate that these patients may be managed with ambulatory surgery.

METHODS

The experience of one endocrine surgeon with thyroidectomy for Graves' was examined from January 2016-November 2017. Forty-one patients met criteria. Patient demographics, perioperative parameters, and postoperative outcomes including emergency department utilization and readmission were recorded.

RESULTS

Mean age was 31.5 ± 17.0 years, with 80% females. Mode ASA score was 3, and median operative time was 77 minutes (43-132). Complications included transient hypocalcaemia in 12%, and temporary laryngeal nerve palsy in 9.7%, with no permanent complications. Two patients were admitted immediately postoperatively for non-medical reasons. Thirty-day emergency rdepartment visits were noted in 9.7%, with subsequent readmission of 7%.

CONCLUSIONS

Outpatient total thyroidectomy is safe and effective with acceptable morbidity in the Graves' patient.

The use of ICG enhanced fluorescence for the evaluation of parathyroid gland preservation

Indocyanine green (ICG) enhanced fluorescence imaging is recent innovation as the "real-time intraoperative imaging" technique. Many clinical studies have been reported in the literature which use different devices and techniques that employ various doses and usages of ICG as a non-specific contrast agent. Several groups have performed studies in endocrine surgery, especially with regards to parathyroid-related outcomes after thyroid and parathyroid surgery. However, there is no consensus on the technical details that should be applied. With this study, we aimed to review the current literature on potential use of intraoperative ICG angiography for evaluating parathyroid gland (PTG) preservation.

Is Outpatient Thyroid Surgery for Everyone?

Thyroidectomy is a common surgical procedure. Traditionally, surgeons have performed thyroidectomy on an inpatient basis. However, consistent with current trends in surgery, some practices are transitioning thyroidectomy to an outpatient setting. Although concerns for hypocalcemia and postoperative bleeding exist regardless of surgeon experience, multiple studies demonstrate that outpatient thyroidectomy is safe in the hands of high-volume surgeons. Indeed, experienced thyroid surgeons who perform thyroidectomy in an outpatient setting experience excellent patient outcomes and reduced costs. However, outpatient thyroidectomy may not be suitable for all surgeons, hospitals, or patients. When evaluating whether to implement an outpatient thyroid program, a practice should consider a number of important factors including the team performing the procedure, the hospital, and the patient. With the appropriate staff education and experience, hospital setting, and patient selection, practices in a multitude of settings can successfully develop a safe, cost-effective outpatient thyroid program.

Postoperative Outcomes in Graves' Disease Patients: Results from the Nationwide Inpatient Sample Database

BACKGROUND

Current surgical indications for Graves' disease include intractability to medical and/or radioablative therapy, compressive symptoms, and worsening ophthalmopathy. Total thyroidectomy for Graves' disease may be technically challenging and lead to untoward perioperative outcomes. This study examines outcomes in patients with Graves' disease who underwent total thyroidectomy and assesses its safety for this patient population.

METHODS

A retrospective cross-sectional analysis was performed using the Nationwide Inpatient Sample database from 2006 to 2011. Total thyroidectomy performed in patients with Graves' disease, benign multinodular goiter (MNG), and thyroid cancer was identified. Demographic factors, comorbidities, and postoperative complications were evaluated. Chi-square, one-way analysis of variance, and risk-adjusted multivariable logistic regression were performed.

RESULTS

Of 215,068 patients who underwent total thyroidectomy during the study period, 11,205 (5.2%) had Graves' disease, 110,124 (51.2%) MNG, and 93,739 (43.6%) thyroid malignancy. Patients with Graves' disease were younger than MNG and thyroid cancer patients (M_age = 42.8 years vs. 55.5 and 51.0 years; p < 0.01). The Graves' disease group included a higher proportion of women (p < 0.01) and nonwhites (p < 0.01). Postoperatively, Graves' patients had significantly higher rates of hypocalcemia (12.4% vs. 7.3% and 10.3%; p < 0.01), hematomas requiring reoperation (0.7% vs. 0.4% and 0.4%; p < 0.01), and longer mean hospital stay (2.7 days vs. 2.4 and 2.2 days; p < 0.01) compared to MNG and thyroid cancer patients, respectively. On risk-adjusted multivariate logistic regression, Graves' disease was independently associated with a higher risk of vocal-cord paralysis (odds ratio [OR] = 1.36 [confidence interval (CI) 1.08-1.69]), tracheostomy (OR = 1.35 [CI 1.1-1.67]), postoperative hypocalcemia (OR = 1.65 [CI 1.54-1.77]), and hematoma requiring reoperation (OR = 2.79 [CI 2.16-3.62]) compared to MNG patients. High-volume centers for total thyroidectomy were independently associated with lower risk of postoperative complications, including in patients with Graves' disease.

CONCLUSIONS

Despite low overall morbidity following total thyroidectomy, Graves' disease patients are at increased risk of postoperative complications, including bleeding, vocal-cord paralysis, tracheostomy, and hypocalcemia. These risks appear to be lower when performed at high-volume centers, and thus referral to these centers should be considered. Total thyroidectomy may therefore be a safe treatment option for appropriately selected patients with Graves' disease when performed by experienced surgeons.

Rescue pre-operative treatment with Lugol's solution in uncontrolled Graves' disease

BACKGROUND

Graves' disease is a common cause of hyperthyroidism. Three therapies have been used for decades: pharmacologic therapy, surgery and radioiodine. In case of adverse events, especially agranulocytosis or hepatotoxicity, pre-treatment with Lugol's solution containing iodine/potassium iodide to induce euthyroidism before surgery could be advocated, but this has rarely been reported.

METHODS

All patients hospitalised due to uncontrolled hyperthyroidism at the Karolinska University Hospital 2005-2015 and treated with Lugol's solution were included. All electronic files were carefully reviewed manually, with focus on the cause of treatment and admission, demographic data, and effects of iodine on thyroid hormone levels and pulse frequency.

RESULTS

Twenty-seven patients were included. Lugol's solution had been chosen due to agranulocytosis in 9 (33%), hepatotoxicity in 2 (7%), other side effects in 11 (41%) and poor adherence to medication in 5 (19%). Levels of free T4, free T3 and heart rate decreased significantly after 5-9 days of iodine therapy (free T4 53-20 pmol/L, P = 0.0002; free T3 20-6.5 pmol/L, P = 0.04; heart rate 87-76 beats/min P = 0.0007), whereas TSH remained unchanged. Side effects were noted in 4 (15%) (rash n = 2, rash and vomiting n = 1, swelling of fingers n = 1). Thyroidectomy was performed in 26 patients (96%) and one was treated with radioiodine; all treatments were without serious complications.

CONCLUSION

Treatment of uncontrolled hyperthyroidism with Lugol's solution before definitive treatment is safe and it decreases thyroid hormone levels and heart rate. Side effects were limited. Lugol's solution could be recommended pre-operatively in Graves' disease with failed medical treatment, especially if side effects to anti-thyroid drugs have occurred.

A prospective cohort study of novel functional types of parathyroid glands in thyroidectomy: In situ preservation or auto-transplantation?

The best method of preventing hypoparathyroidism after thyroidectomy is to keep parathyroid glands in situ. However, hypoparathyroidism still regularly occurs with the existing parathyroid classification system, and the incidence of permanent hypoparathyroidism has not been reduced. We created a novel system for classifying parathyroid glands that can guide parathyroid preservation in thyroidectomy.We prospectively observed parathyroid glands using the new system in 218 neck surgeries, compared with 132 under the traditional system from January 2014 to September 2015 at a single clinic center. Briefly, we classified parathyroid glands as follows: Type A, no dependency on the thyroid; B1, partial blood supply from the thyroid but retains adequate blood supply after removal of the thyroid; B2, partial blood supply from the thyroid and becomes devascularized after the removal of the thyroid; B3, blood supply mostly from the thyroid; and C, blood supply completely dependent on the thyroid. The classifications were used to decide between in situ preservation or auto-transplantation.The most common type of parathyroid gland was type B1 (53.77%), followed by type A (20.89%), which are the perfect categories for in situ preservation. Type B2 (17.52%) and type B3 (1.21%) have a chance to be kept in situ. For type C (6.61%), in situ preservation is impossible. When in-situ preservation is ruled out, parathyroid auto-transplantation is an alternative, with partial or total gland tissue, depending on the classification and the surgeon's discretion. Among the patients who were classified under the new system, 43.6% presented with transient hypoparathyroidism (symptoms lasting ≤6 months) after surgery, versus 42.4% in the old system, which was not a significant difference. However, permanent hypothyroidism (symptoms lasting >6 months) was not detected in the applied group, but in 3.0% of patients in the nonapplied group (P = 0.01).Our novel functional nomenclature system for parathyroid glands can provide a guide for preserving parathyroid function. For certain types, such as type B2 and C, instead of being kept in situ, auto-transplantation of partial or total parathyroid tissue is a prudent choice to ensure continued function.

Short-Term PTH(1-34) Therapy in Children to Correct Severe Hypocalcemia and Hyperphosphatemia due to Hypoparathyroidism: Two Case Studies

The standard treatment of hypoparathyroidism is to control hypocalcemia using calcitriol and calcium supplementation. However, in severe cases this approach is insufficient, and the risks of intravenous (i.v.) calcium administration and prolonged hospitalization must be considered. While the use of recombinant human parathyroid hormone 1-34 [rhPTH(1-34)] for long-term control of hypocalcemia has been established, the benefits of short-term rhPTH(1-34) treatment in children have not been explored. We report two patients with hypoparathyroidism treated with rhPTH(1-34). Patient 1 is a 10-year-old female with polyglandular autoimmune syndrome type 1. Patient 2 is a 12-year-old female with hypoparathyroidism after total thyroidectomy. Both patients showed poor response to i.v. and oral calcium and calcitriol, and patient 1 did not respond to phosphate binders. Patient 1 had rapid increase in serum calcium with a decrease in serum phosphate after a 3-day course of subcutaneous rhPTH(1-34). Patient 2 had normalization of calcium and phosphate levels after a 7-day course of rhPTH(1-34). These cases support a role for rhPTH(1-34) in the acute management of hypoparathyroidism in hospitalized patients to more rapidly correct hypocalcemia and hyperphosphatemia, shorten hospitalization, and reduce the need for frequent i.v. calcium boluses.

A Prospective Study Comparing the Efficacy and Surgical Outcomes of Harmonic Focus Scalpel Versus LigaSure Small Jaw in Thyroid and Parathyroid Surgery

Background The use of sealing devices has been established in thyroid surgeries. Recently, LigaSure Small Jaw (LS), a new device that utilizes bipolar energy, was approved by the Food and Drug Administration for use in different head and neck procedures. The purpose of this study is to assess the efficiency and safety of LS use in thyroid surgery compared to Harmonic Focus Scalpel (HS), a well-established device. Methods A prospective study was conducted to compare the efficacy of LS versus the HS. We evaluated 301 patients who underwent surgery at a North American academic institution. Patients were allocated into two groups according to LS or HS use. All patients underwent vocal cord assessment using direct laryngoscopy preoperatively and postoperatively. Analyses were performed to examine the difference in perioperative outcomes resulting from the utilization of either device. Results No difference was seen in operative time between both groups (124.20 ± 68.44 minutes in HS vs 125.20 ± 72.13 minutes in LS, P = .99). Overall complications were similar between both groups (22.86% in HS vs 13.84% in LS, P = .05). However, LS use was also associated with a lower incidence of postoperative transient hypocalcemia as compared to the HS (P = .025). No significant difference was found between both groups regarding the incidence of recurrent laryngeal nerve injury (P = .52). Conclusion The use of the LS is safe, feasible, and is associated with comparable outcomes to HS. Both intraoperative and postoperative variables were similar between both devices. Future larger studies are warranted to further investigate the effect on postoperative transient hypocalcemia.

Prediction of permanent hypoparathyroidism after total thyroidectomy

BACKGROUND

Hypoparathyroidism is a common complication with thyroid surgery. The ability to predict a high risk of permanent hypoparathyroidism is important for individual prognosis and follow-up.

METHODS

Permanent hypoparathyroidism, defined as continuing need for vitamin D medication at 1-year post-operatively, was investigated in patients after total thyroidectomy. Blood levels of calcium and parathyroid hormone (PTH) were measured intra-operatively, the day after surgery and at 1 month post-operatively. Logistic regression analysis was performed to investigate the risk of vitamin D treatment at last follow-up, calculated as odds ratios (ORs) with 95 % confidence intervals (CIs). Patients were followed until cessation of vitamin D and/or calcium medication, until death, loss to follow-up, or end of follow-up, whichever came first.

RESULTS

A total of 519 patients were included. The median (range) follow-up in patients unable to cease vitamin D was 2.7 (1.2-10.3) years. The rate of permanent hypoparathyroidism was 10/519, 1.9 %. Parathyroid auto-transplantation was performed in 90/519 (17.3 %) patients. None of these developed permanent hypoparathyroidism, nor did any patient with normal PTH day 1 (>1.6 pmol/l or 15 pg/ml). The adjusted risk (OR, 95 % CI) for permanent hypoparathyroidism for log PTH on day 1 was 0.25 (0.13-0.50). In patients not auto-transplanted and with unmeasurable PTH day 1 (<0.7 pmol/l or 6.6 pg/ml), 8/42 (19.2 %) developed permanent hypoparathyroidism.

CONCLUSIONS

Auto-transplantation protects against permanent hypoparathyroidism, whereas low PTH day 1 is associated with high risk.

Pediatric thyroidectomy in a high volume thyroid surgery center: Risk factors for postoperative hypocalcemia

INTRODUCTION

Hypocalcemia is a common complication following thyroid surgery. We seek to report on our experience in pediatric thyroidectomy in a high volume thyroid surgery center and accurately assess the incidence of postoperative hypocalcemia.

MATERIALS AND METHODS

A retrospective review of patients aged 18 and younger who underwent thyroid surgery between 1992 and 2013. The primary endpoints were the occurrence of postoperative hypocalcemia as by defined as a nadir calcium <8.0mg/dL and being discharged on oral calcium supplementation, need for intravenous calcium and the occurrence of permanent hypoparathyroidism.

RESULTS

171 patients who underwent 186 thyroid operations were analyzed. The average age was 15.4years with 82.3% female. The most common indications for surgery were nodular disease (74.7%) and hyperthyroidism (12.4%). 24 patients (12.9%) experienced postoperative hypocalcemia with 13 (7.0%) requiring intravenous calcium infusion. One patient (0.9%) experienced permanent hypoparathyroidism. Risk factors for postoperative hypocalcemia included total thyroidectomy (OR 7.39, p<0.01), central and bilateral lateral neck dissection (OR 22.26, p=0.01), Graves' disease (OR 3.99, p=0.02), and malignancy (OR 2.96, p=0.03).

CONCLUSIONS

Pediatric patients who undergo total thyroidectomy for underlying malignancy or Graves' disease and those who have more extensive nodal dissections are at increased risk of developing this postoperative hypocalcemia. These patients may benefit from more vigilant preoperative preparation and postoperative calcium and vitamin D supplementation.

Defining the syndromes of parathyroid failure after total thyroidectomy

Acute and chronic parathyroid insufficiency syndromes are the most common complication after total thyroidectomy. Permanent hypoparathyroidism imposes an important medical burden on patient lifestyle due to the need for lifetime medication, regular visits and significant long-term costs. Its true prevalence has been underestimated due to lack of clear definitions, inadequate follow-up and conflicts of interest when reporting individual patient series. The aim of this review is to propose precise definitions for the different syndromes associated to parathyroid failure based on the follow-up and management of patients developing hypocalcemia (<8 mg/dL at 24 hours) after first-time total thyroidectomy for cancer or goiter at our unit. Short and long-term post-thyroidectomy parathyroid failure presents as three different metabolic syndromes: (I) postoperative hypocalcemia is defined as a s-Ca <8 mg/dL (<2 mmol/L) within 24 hours after surgery requiring calcium/vit D replacement therapy at the time of hospital discharge; (II) protracted hypoparathyroidism as a subnormal iPTH concentration (<13 pg/mL) and/or need for calcium/vit D replacement at 4-6 weeks; and (III) permanent hypoparathyroidism as a subnormal iPTH concentration (<13 pg/mL) and/or need for calcium/vit D replacement 1 year after total thyroidectomy. Each of these syndromes has its own pattern of recovery and should be approached with different therapeutic strategies.

Importance of in situ preservation of parathyroid glands during total thyroidectomy

Background

Parathyroid failure is the most common complication after total thyroidectomy but factors involved are not completely understood. Accidental parathyroidectomy and parathyroid autotransplantation resulting in fewer than four parathyroid glands remaining in situ, and intensity of medical treatment of postoperative hypocalcaemia may have relevant roles. The aim of this study was to determine the relationship between the number of parathyroid glands remaining in situ and parathyroid failure after total thyroidectomy.

Methods

Consecutive patients undergoing first-time total thyroidectomy were studied prospectively, recording the number of Parathyroid Glands Remaining In Situ (PGRIS = 4 − (glands autografted + glands in the specimen)) and the occurrence of postoperative hypocalcaemia, and protracted and permanent hypoparathyroidism. Demographic, disease-related, laboratory and surgical variables were recorded. Patients were classified according to the PGRIS number into group 1–2 (one or two PGRIS), group 3 (three PGRIS) and group 4 (all four glands remaining in situ), and were followed for at least 1 year.

Results

A total of 657 patients were included, 43 in PGRIS group 1–2, 186 in group 3 and 428 in group 4. The prevalence of hypocalcaemia, and of protracted and permanent hypoparathyroidism was inversely related to the PGRIS score (group 1–2: 74, 44 and 16 per cent respectively; group 3: 51·1, 24·7 and 6·5 per cent; group 4: 35·3, 13·1 and 2·6 per cent; P &lt; 0·001). Intact parathyroid hormone concentrations at 24 h and 1 month were inversely correlated with PGRIS score (P &lt; 0·001). Logistic regression identified PGRIS score as the most powerful variable influencing acute and chronic parathyroid failure. In addition, a normal–high serum calcium concentration 1 month after thyroidectomy influenced positively the recovery rate from protracted hypoparathyroidism in all PGRIS categories.

Conclusion

In situ parathyroid preservation is critical in preventing permanent hypoparathyroidism after total thyroidectomy. Active medical treatment of postoperative hypocalcaemia has a positive synergistic effect.

Severe Vitamin D Deficiency

Objective

To assess the role of preoperative serum 25 hydroxyvitamin D as predictor of hypocalcemia after total thyroidectomy.

Study Design

Retrospective cohort study.

Setting

University teaching hospital.

Subjects and Methods

All consecutively performed total and completion thyroidectomies from February 2007 to December 2013 were reviewed through a hospital database and patient charts. The relationship between postthyroidectomy laboratory hypocalcemia (serum calcium ≤2 mmol/L), clinical hypocalcemia, and preoperative serum 25 hydroxyvitamin D level was evaluated.

Results

Two hundred thirteen patients were analyzed. The incidence of postoperative laboratory and clinical hypocalcemia was 19.7% and 17.8%, respectively. The incidence of laboratory and clinical hypocalcemia among severely deficient (<25 nmol/L), deficient (<50 nmol/L), insufficient (<75 nmol/L), and sufficient (≥75 nmol/L) serum 25 hydroxyvitamin D levels was 54% versus 33.9%, 10% versus 18%, 2.9% versus 11.6%, and 3.1% versus 0%, respectively. Multiple logistic regression analysis revealed preoperative severe vitamin D deficiency as a significant independent predictor of postoperative hypocalcemia (odds ratio [OR], 7.3; 95% confidence interval [CI], 2.3-22.9; P = .001). Parathyroid hormone level was also found to be an independent predictor of postoperative hypocalcemia (OR, 0.6; 95% CI, 0.5-0.8; P = .002).

Conclusion

Postoperative clinical and laboratory hypocalcemia is significantly associated with low levels of serum 25 hydroxyvitamin D. Our findings identify severe vitamin D deficiency (<25 nmol/L) as an independent predictor of postoperative laboratory hypocalcemia. Early identification and management of patients at risk may reduce morbidity and costs.

Preventing postoperative hypocalcemia in patients with Graves disease: a prospective study

BACKGROUND

Hypocalcemia occurs after total thyroidectomy (TT) for Graves disease via parathyroid injury and/or from increased bone turnover. Current management is to supplement calcium after surgery. This study evaluates the impact of preoperative calcium supplementation on hypocalcemia after Graves TT.

METHODS

A prospective study of patients with Graves disease undergoing TT was performed. Patients with Graves disease managed over a 9-month period took 1 g of calcium carbonate (CC) three times a day for 2 weeks before TT. Those managed the previous year without supplementation served as historic controls. Age-, gender-, and thyroid weight-matched, non-Graves TT patients were procedure controls. Patient demographics, postoperative laboratory values, complaints, and medications were reviewed. Parathyroid hormone (PTH)-based postoperative protocols dictated postoperative CC and calcitriol use.

RESULTS

Forty-five patients with Graves disease were treated with CC before TT, and 38 patients with Graves disease were not. Forty control subjects without Graves disease were identified. Age, gender, and thyroid weight were comparable. Preoperative calcium and PTH levels were equivalent. PTH values immediately after surgery, at postoperative day 1, and at 2-week follow-up were equivalent. Postoperative use of scheduled CC (p = 0.10) and calcitriol (p = 0.60) was similar. Postoperatively, patients with untreated Graves disease had lower serum calcium levels than pretreated patients with Graves disease or control subjects without Graves disease (8.3 mg/dL vs. 8.6 vs. 8.6, p = 0.05). Complaints of numbness and tingling were more common in nontreated Graves disease (26%) than in pretreated Graves disease (9%) or in control subjects without Graves disease (10%, p < 0.05).

CONCLUSIONS

Calcium supplementation before TT for Graves disease significantly reduced biochemical and symptomatic postoperative hypocalcemia. Preoperative calcium supplementation is a simple treatment that can reduce symptoms of hypocalcemia after Graves TT.

Left-shifted relation between calcium and parathyroid hormone in Graves' disease

BACKGROUND

Patients with Graves' disease (GD) have disturbances in calcium regulation with manifestations such as postoperative hypocalcemia. We have investigated the thyroid as well as the parathyroid function in detail.

MATERIALS AND METHOD

A series of patients undergoing total thyroidectomy for GD (n = 56) or multinodular goiter (MNG; n = 50) were scrutinized for postoperative hypocalcemia and a need for calcium and/or vitamin D substitution. A citrate-calcium (CiCa) clamp was used in 14 patients and 21 controls to quantify the secretion of PTH in relation to the ionized plasma calcium level. The set point, equal to the plasma-ionized calcium concentration at which 50% of the maximal secretion of PTH is inhibited, as well as other CiCa-related parameters were calculated.

RESULTS

Hypocalcemia was present in 48% of GD and 41.2% of patients with MNG postoperatively. Patients with GD had lower calcium levels, 18% had serum Ca less than 2.00 mmol/L compared with 4.0% in the MNG group (P = .02). A higher degree of GD patients were given parenteral calcium substitution during the hospital stay (3.6% vs 0 %) and oral calcium substitution at discharge (48% vs 10%), although they had normal vitamin D3 levels. The GD group showed a significantly left-shifted set point compared with the normal group on the CiCa clamp, 1.16 mmol/L vs 1.20 mmol/L (P < .001) as well as an increased PTH release to hypocalcemic stimulus. GD patients also show an association between degree of subclinical toxicosis at time of surgery and risk for developing postoperative hypocalcemia.

CONCLUSION

Patients with GD demonstrate dysregulation of the calcium homeostasis by several parameters. GD patients have lower postoperative serum calcium compared with patients with MNG, lower calcium/PTH set point, and a significantly increased release of PTH to hypocalcemic stimulus compared with controls. The CiCa clamp response in GD patients with normal 25-hydroxyvitamin D3 levels mimics that of obese patients in which vitamin D insufficiency has been proposed as an underlying cause.

Systematic review and meta-analysis of predictors of post-thyroidectomy hypocalcaemia

BACKGROUND

Hypocalcaemia is common after thyroidectomy. Accurate prediction and appropriate management may help reduce morbidity and hospital stay. The aim of this study was to perform a systematic literature review and meta-analysis of predictors of post-thyroidectomy hypocalcaemia.

METHODS

A systematic search of PubMed, EMBASE and the Cochrane Library databases was undertaken, and the quality of manuscripts assessed using a modified Newcastle-Ottawa Scale.

RESULTS

Some 115 observational studies were included. The median (i.q.r.) incidence of transient and permanent hypocalcaemia was 27 (19-38) and 1 (0-3) per cent respectively. Independent predictors of transient hypocalcaemia included levels of preoperative calcium, perioperative parathyroid hormone (PTH), preoperative 25-hydroxyvitamin D and postoperative magnesium. Clinical predictors included surgery for recurrent goitre and reoperation for bleeding. A calcium level lower than 1·88 mmol/l at 24 h after surgery, identification of fewer than two parathyroid glands (PTGs) at surgery, reoperation for bleeding, Graves' disease and heavier thyroid specimens were identified as independent predictors of permanent hypocalcaemia in multivariable analysis. Factors associated with transient hypocalcaemia in meta-analyses were inadvertent PTG excision (odds ratio (OR) 1·90, 95 per cent confidence interval 1·31 to 2·74), PTG autotransplantation (OR 2·03, 1·44 to 2·86), Graves' disease (OR 1·75, 1·34 to 2·28) and female sex (OR 2·28, 1·53 to 3·40).

CONCLUSION

Perioperative PTH, preoperative vitamin D and postoperative changes in calcium are biochemical predictors of post-thyroidectomy hypocalcaemia. Clinical predictors include female sex, Graves' disease, need for parathyroid autotransplantation and inadvertent excision of PTGs.

Perioperative indicators of hypocalcemia in total thyroidectomy: the role of vitamin D and parathyroid hormone

BACKGROUND

Hypocalcemia is a common complication of thyroidectomy. The aim of this study was to identify risk factors for this problem.

METHODS

This prospective analysis included 111 patients undergoing total or completion thyroidectomy. Preoperative vitamin D levels and postoperative day 1 parathyroid hormone levels were analyzed for their predictive effects on postoperative hypocalcemia.

RESULTS

Patients with ionized calcium <4.4 mg/dL had significantly lower mean parathyroid hormone levels than normocalcemic patients (13.0 vs 28.4 pg/mL, P < .001). Parathyroid hormone levels were also significantly lower in symptomatic patients (11.0 vs 28.4 pg/mL, P < .001). Preoperative vitamin D level, body mass index, gender, and pathologic findings were not associated with low calcium levels or symptoms of hypocalcemia.

CONCLUSIONS

Younger age and low postoperative parathyroid hormone levels are predictive of symptomatic hypocalcemia. A parathyroid hormone level outside of the reference range may indicate a need for more aggressive postoperative calcium supplementation and treatment with activated vitamin D. Older patients with normal postoperative parathyroid hormone levels may be safely discharged with appropriate calcium supplementation.

Total thyroidectomy for Graves' disease: compliance with American Thyroid Association guidelines may not always be necessary

BACKGROUND

Total thyroidectomy (TT) is the preferred operative approach to Graves' disease. Current guidelines of the American Thyroid Association call for the administration of potassium iodide (KI) and achievement of euthyroid state before operation. Small numbers and a mixture of operative approaches spanning several decades hinder previous operative series. We present the outcomes for TT at a single high-volume center.

METHODS

A retrospective cohort study was conducted on 165 patients undergoing TT for Graves' disease from July 2007 to May 2012.

RESULTS

Mean age was 43 years (range, 17-78), and 128 patients (78%) were female. A total of 95% of patients were on methimazole or propylthiouracil, and 42% remained hyperthyroid at time of TT. Only 3 (2%) patients received KI. Mean operative time was 132 minutes (range, 59-271). Mean gland size and blood loss were 41 g (range, 8-180) and 55 mL (range, 10-1050), respectively. No patient developed thyroid storm. Median follow-up was 7.5 months. Temporary and permanent hypocalcemia developed in 51 (31%) and 2 patients (1.2%), respectively. Temporary and permanent recurrent laryngeal nerve paresis occurred in 12 (7%) and one (0.6%) patient, respectively. Sixty-one (37%) patients experienced at least one complication. On multivariate analysis, patient age younger than 45 years (odds ratio 2.93, 95% confidence interval 1.39-6.19) and obesity (odds ratio 2.11, 95% confidence interval 1.00-4.43) were associated with the occurrence of complications.

CONCLUSION

This high-volume surgeon experience demonstrates no appreciable detriment to patient outcomes when recommendations of the American Thyroid Association for routine use of KI and euthyroid state before thyroidectomy are not met. Transient hypocalcemia and hoarseness are frequent complications of TT for Graves' disease, resolving within 6 months in most patients. Age younger than 45 years and obesity are risk factors for postoperative complications.

A Case of Hypocalcemia with Severe Vitamin D Deficiency following Treatment for Graves' Disease with Methimazole

We herein report the case of a 41-year-old Japanese female office worker who developed symptomatic hypocalcemia with severe vitamin D deficiency following treatment for Graves' disease with methimazole. The patient's hypocalcemia was mainly caused by vitamin D deficiency due to unbalanced diets and inadequate exposure to sunlight in addition to the resolution of hyperthyroidism. Vitamin D deficiency is increasing worldwide, and it has been more recently shown to relate to the pathogenesis of Graves' disease. However, vitamin D deficiency as a cause of hypocalcemia has received little attention. Taken together, this case suggests that we should take more care in calcium kinetics and vitamin D status during treatment for Graves' disease with antithyroid drugs.

Hypocalcaemia following total thyroidectomy: An analysis of 806 patients

BACKGROUND

Permanent hypocalcaemia following thyroidectomy causes considerable morbidity. This prospective observational study aims to define the factors likely to predict hypocalcaemia following total thyroidectomy.

MATERIALS AND METHODS

Patients who were subjected to total thyroidectomy during January 2005 to December 2009 were followed up for a minimum period of 1 year. Efficacy of an intraoperative parathyroid hormone assay to predict hypocalcaemia was validated.

RESULTS

Overall incidence of hypocalcaemia was 23.6% (n = 190) and that of permanent hypocalcaemia was 1.61% (n = 13). Onset was delayed up to 3(rd) postoperative day in 13 patients. Hypocalcaemia was significantly associated with thyroidectomy for Grave's Disease (P = 0.001), Hashimoto's thyroiditis (P = 0.003), and with incidental parathyroidectomy (P = 0.006). The intraoperative assay of parathyroid hormone showed low sensitivity (0.5) and satisfactory specificity (0.9) in predicting hypocalcemia.

CONCLUSION

Hypocalcemia could manifest late in the immediate postoperative period and this may explain latent hypocalcemia. High incidence of hypocalcaemia noted in Grave's Disease could be due to the autoimmunity since same feature was noted associated with Hashimoto's thyroiditis and the incidence of hypocalcaemia was not high in the subgroup with toxic nodular goiter. The incidence of hypocalcemia was not affected by age or sex.