A retrospective cohort study: do patients with graves' disease need to be euthyroid prior to surgery?

Does Graves' Disease Truly Increase the Risk of Complications After Total Thyroidectomy?

INTRODUCTION

Total thyroidectomy (TTx) has been reported to be more challenging in patients with Graves' disease, especially in those who are hyperthyroid at the time of surgery. Our aim was to compare outcomes in patients undergoing TTx for Graves' disease compared to other thyroid diseases at a large academic institution with high-volume fellowship-trained endocrine surgeons.

METHODS

In our retrospective analysis from December 2015 to May 2023, patients undergoing TTx for Graves' disease were compared to those undergoing TTx for all other indications excluding advanced malignancy (poorly differentiated thyroid cancer and concomitant neck dissections). Patient demographics, biochemical values, and postoperative outcomes were compared. A subgroup analysis was performed comparing hyperthyroid to euthyroid patients at the time of surgery.

RESULTS

There were 589 patients who underwent TTx, of which 227 (38.5%) had Graves' disease compared to 362 (61.5%) without. Intraoperatively in Graves' patients, nerve monitoring was used more frequently (65.6% versus 57.1%; P = 0.04) and there was a higher rate of parathyroid autotransplantation (32.0% versus 14.4%; P < 0.01). Postoperatively, transient voice hoarseness occurred less frequently (4.8% versus 13.6%; P < 0.01) and there was no difference in temporary hypocalcemia rates or hematoma rates. In our subgroup analysis, 83 (36%) of Graves' patients were hyperthyroid (thyroid-stimulating hormone < 0.45 and free T4 > 1.64) at the time of surgery and there were no differences in postoperative complications compared to those who were euthyroid.

CONCLUSIONS

At a high-volume endocrine surgery center, TTx for Graves' disease can be performed safely without significant differences in postoperative outcomes. Hyperthyroid patients demonstrated no differences in postoperative outcomes.

Preoperative preparation for Graves' disease

Thyroidectomy is always regarded as the crucial treatment for Graves' disease, especially in cases of poor efficacy or excessive side effects of antithyroid- drugs and 131I radioiodine therapy. To decrease the incidence of hemorrhage, thyroid storms and other severe complications during the perioperative period, surgeons explore different therapies to prepare for thyroidectomy. We performed a review of preoperative preparation with a focus on the Graves' disease population. Most of the previous schemes are effective, which contributes to the smooth operation of patients, but there is no unified standard for preoperative preparation. This review aims to summarize the preoperative preparation of Graves' disease and the latest developments. Prospective studies with longer follow up-up periods are required to select appropriate preoperative regimens based on personal thyroid statements and to identify target populations of benefit.

Postoperative Hypocalcemia in Hyperthyroid Patients: The Parathyroids Aren't Always to Blame

INTRODUCTION

Hypocalcemia is commonly reported after thyroidectomy and has multiple possible etiologies including: parathyroid devascularization, reactive hypoparathyroidism from relative hypercalcemia in thyrotoxicosis, and abrupt reversal of thyrotoxic osteodystrophy. In patients that are actively hyperthyroid and undergoing thyroidectomy, it is not known how many experience hypocalcemia from nonhypoparathyroidism etiologies. Therefore, our aim was to examine the relationship among thyrotoxicosis, hypocalcemia, and hypoparathyroidism.

METHODS

A retrospective review was performed of prospectively-collected data from all patients undergoing thyroidectomy for hyperthyroidism by 4 surgeons from 2016 to 2020. All patients carried a diagnosis of Graves' disease or toxic multinodular goiter. Patient demographics, preoperative medications, laboratory reports, and postoperative medications were reviewed. Hypocalcemia within the first month of surgery despite a normal parathyroid hormone (PTH) level was the primary outcome of interest and was compared between patients with and without thyrotoxicosis. Secondary outcomes were duration of postoperative calcium use and the relationship between preoperative calcium supplementation and postoperative calcium supplementation. Descriptive statistics, Wilcoxon rank-sum, and chi-square tests were used for bivariate analysis, as appropriate.

RESULTS

A total of 191 patients were identified, with mean age of 40.5 y (range 6-86). Most patients were female (80%) and had Graves' disease (80%). At the time of surgery, 116 (61%) had uncontrolled hyperthyroidism (thyrotoxic group, Free Thyroxine >1.64 ng/dL or Free Triiodothyronine > 4.4 ng/dL), with the remaining 75 (39%) considered euthyroid. Postoperative hypocalcemia (calcium < 8.4 mg/dL) developed in 27 (14%), while hypoparathyroidism (PTH < 12 pg/mL) was observed in 39 (26%). Thyrotoxic patients comprised a majority of those with hypocalcemia (n = 22, 81%, P = 0.01) and hypoparathyroidism immediately following surgery (n = 14, 77%, P = 0.04). However, a majority of initially hypocalcemic, thyrotoxic patients had normal PTH values within the first month after surgery (n = 17, 85%), pointing to a potential nonparathyroid etiology. On bivariate analysis, no significant relationship was found for thyrotoxic patients with initial postoperative hypocalcemia (18%) and hypoparathyroidism <1-month after surgery (29%, P = 0.29) or between 1 and 6 mo after surgery (2%, P = 0.24). Of the 19 patients in the nonhypoparathyroidism group, 17 (89%) were off all calcium supplements by 6 mo postop.

CONCLUSIONS

In patients with hyperthyroidism, those in active thyrotoxicosis at time of surgery have a higher rate of postoperative hypocalcemia compared to euthyroid patients. When hypocalcemia lasts >1 mo postoperatively, data from this study suggest that hypoparathyroidism may not be the primary etiology in many of these patients, who typically require calcium supplementation no more than 6 mo postoperatively.

Changes in TSH, T4, T3 and Thyroglobulin Levels throughout Total Thyroidectomy

Introduction: To assess the impact of total thyroidectomy on thyroid function. Methods: Monocentric observational prospective study. Patients who benefited from a total thyroidectomy in the Department of Otolaryngology-Head and Neck Surgery between September 2017 and July 2019 were included. Three blood samples were taken from each patient during the perioperative period: preoperatively (T₀), intraoperatively (T₁), and postoperatively (T₂). Changes in TSH, T4, T3, and thyroglobulin levels were evaluated from T₀ to T₂. Epidemiological data were retrieved from the medical charts. Statistical analyses were performed for the entire cohort and subgroups regarding preoperative treatment and type of disease. Results: Seventy-seven patients were included in the study. T4 and thyroglobulin levels increased significantly from T₀ to T₁. TSH, T4, T3, and thyroglobulin levels decreased significantly from T₁ to T₂. Conclusions: Our study confirmed the hypothesis of variable kinetics of thyroid hormone levels associated with the manipulation of the thyroid gland during surgery, but none of these changes resulted in clinical effects, including thyrotoxicosis.

Time to Euthyroidism and Its Determinants Among Thyrotoxicosis Patients on Anti-Thyroid Drug Who Attend to Medical and Ambulatory Clinics of South Tigrai General Hospitals

Purpose

To determine the time to euthyroidism and its determinants among thyrotoxicosis patients on anti-thyroid drug attending the medical and ambulatory clinics of South Tigrai General Hospitals, Ethiopia, 2015–2020.

Methods

A multi-center retrospective cohort study was conducted from March 30, 2020, to July 30, 2020, among adult thyrotoxicosis patients who received anti-thyroid medications in the medical and chronic ambulatory clinics of South Tigrai General Hospitals, Ethiopia. Epi-data manager version 3.1 software was used for data entry and then exported to STATA version 15 for windows for analysis. Cox proportional hazards regression model was used to determine the determinants of time to euthyroidism and the summary measures of the adjusted hazard ratio with a 95% CI were presented, and P-value < 0.05 used to declare the statistical significance.

Results

One hundred and seventy-five (51.9%) thyrotoxicosis patients become euthyroid with the median time to euthyroidism of 9 months, IQR (6–12) months, with a total of 5542 person-months of observation. Age greater than 40 years (AHR = 0.7; 95% CI 0.54–0.96), toxic multi-nodular goiter (AHR = 0.69; 95% CI 0.60–0.87), World Health Organization goiter size three (AHR = 0.78; 95% CI 0.54–0.82) and baseline free thyroxin (AHR = 0.96; 95% CI 0.80–0.99) were the independent determinants of delayed time to euthyroidism.

Conclusion

The time to euthyroidism was longer than the expected time. High baseline free thyroxin, toxic multinodular goiter, elderly patients, and patients with World Health Organization goiter size three were determinants of delayed time to euthyroidism.

The risk of perioperative thyroid storm in hyperthyroid patients: a systematic review

BACKGROUND

Thyroid storm is a feared complication in patients with hyperthyroidism undergoing surgery. We assessed the risk of thyroid storm for different preoperative treatment options for patients with primary hyperthyroidism undergoing surgery.

METHODS

Pubmed, EMBASE, and The Cochrane Library were searched systematically for all studies reporting on adult hyperthyroid patients undergoing elective surgery under general anaesthesia. Selected studies were categorised based on preoperative treatment: no treatment, antithyroid medication (thionamides), iodine, β-blocking medication, or a combination thereof. Treatment effect, that is restoring euthyroidism, was extracted from the publications if available. Risk of bias was assessed using the Risk of Bias in Non-randomised Studies of Interventions (ROBINS-I) or the Cochrane Risk of Bias tool for randomised studies.

RESULTS

The search yielded 7009 articles, of which 26 studies published between 1975 and 2020 were selected for critical appraisal. All studies had moderate to critical risk of bias, mainly attributable to risk of confounding, classification of intervention status, and definition of the outcome. All studies reported on thyroidectomy patients. We found no randomised studies comparing the risk of thyroid storm between treated and untreated patients. Cases of thyroid storm were reported in all treatment groups with incidences described ranging from 0% to 14%.

CONCLUSION

Evidence assessing the risk of perioperative thyroid storm is of insufficient quality. Given the seriousness of this complication and the impossibility of identifying patients at increased risk, preoperative treatment of these patients remains warranted.

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.

Perioperative Management and Outcomes of Hyperthyroid Patients Unable to Tolerate Antithyroid Drugs

BACKGROUND

Prior to thyroidectomy for hyperthyroidism, it is recommended that patients are managed with antithyroid drugs (ATDs) and rendered euthyroid to decrease the risk of thyroid storm. However, not all patients tolerate ATD and the risk of thyroid storm during thyroidectomy in these patients is unclear. Therefore, the aim of this study was to compare the management and outcomes of hyperthyroid patients that were on ATDs prior to surgery to those who were not.

STUDY DESIGN

A prospectively maintained, single-institution database was queried for all hyperthyroid patients who were initially treated with ATDs and underwent thyroidectomy from January 1, 2012, to June 18, 2018. Patients were divided into two groups: (1) those on ATDs at surgery (ATD group) and (2) those who could not tolerate and stopped ATDs prior to surgery (no-ATD group). Demographic and clinical data were collected. Primary outcomes were readmissions/emergency department visits and postoperative complications within 30 days of thyroidectomy.

RESULTS

Of the 248 patients, 231 were in the ATD group and 17 (7%) were in the no-ATD group. There were no mortalities or thyroid storm events in either group. There was no difference in Clavien-Dindo Grade 2 or 3 complications between the two groups. There were no ED visits or 30-day readmissions in the no-ATD group compared to 17 (7%) events in the ATD group (p = 1.0).

CONCLUSION

While it is preferable to render patients euthyroid prior to thyroidectomy for hyperthyroidism, results of this study suggest that when patients cannot tolerate ATDs, it is possible to perform thyroidectomy without increased risk of thyroid storm or intra- and postoperative complications.

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.

Comparison of Intra-Operative Vital Sign Changes during Total Thyroidectomy in Patients with Controlled and Uncontrolled Graves' Disease

Thyroid storm (TS) is a life-threatening emergency endocrine condition. Thyroid hormones should be normalized before thyroidectomy is performed in patients with Graves’ disease. However, thyroid hormone levels are inevitably high in patients undergoing surgery. This study analyzed differences in vital sign changes during thyroidectomy between patients with controlled and uncontrolled Graves’ disease and assessed thyroid hormone cutoffs for TS. Preoperative levels of the thyroid hormones free T4 (FT4), T3, and thyroid stimulating hormone (TSH) were retrospectively analyzed in patients who underwent total thyroidectomy for Graves’ disease. Patients were divided into those with uncontrolled Graves’ (UG) disease, defined as preoperative TSH <0.3 µIU/mL and FT4 >1.7 ng/dL, those with controlled Graves’ (CG) disease, those with extremely uncontrolled Graves’ (EUG) disease, defined as TSH <0.3 µIU/mL and FT4 >3.4 ng/dL, and finally, those without EUG (non-EUG). The 29 patients with Graves’ disease included 12 with CG group and 17 with UG. FT4 and T3 concentrations were significantly higher in the UG group. There were no differences in vital sign and anesthetic agent. These 29 patients could also be divided into those with (n = 4) and without EUG (n = 25). The mean age was lower (21.5 vs. 40.9 years, p < 0.001) and the mean operation time was shorter (121.4 vs. 208.8 min, p = 0.003) in the EUG group. Requirements for anesthetic agents were greater in the EUG group. Mean FT4 concentration in the EUG group was 3.8 ng/dL, and there were no changes in vital signs during surgery. Vital sign change during thyroid surgery was not observed in patients with uncontrolled Graves’ disease up to the twice upper normal limit of T4 level.