PARATHYROID HORMONE ASSAY PREDICTS HYPOCALCAEMIA AFTER TOTAL THYROIDECTOMY

Impact of oral administration of calcitriol to prevent symptomatic hypocalcemia after total thyroidectomy: Systematic review and meta-analysis

BACKGROUND

One of the most common complications of total thyroidectomy is post-operative transient or persistent hypoparathyroidism that can cause symptomatic hypocalcaemia. To prevent this complication, shorten the period of hospitalization and reduce morbidity, routine supplementation of oral vitamin D and calcium has been suggested. This systematic review and meta-analysis aims to critically assess the association between pre-operative calcitriol supplementation and post-operative hypocalcaemia.

METHODS

Randomized controlled trial studies were identified by searching PubMed, Scopus, and Google Scholar databases up to 30 March 2023. Screening of titles, abstracts, and full texts of articles were performed, and data were extracted for a meta-analysis.

RESULTS

This meta-analysis includes data from nine randomized controlled trials with a total of 1259 patients but with significant heterogeneity. The results demonstrate that calcium levels were higher in patients who had pre-operative calcitriol supplementation, with a weighted mean difference (WMD) 0.18 (95% confidence interval (CI) = 0.00, 0.37). Pre-operative calcitriol supplementation did not lead to significant changes in parathyroid hormone (PTH) levels, with WMD -0.49 (95% CI: -1.91, 0.94).

CONCLUSION

Pre-operative calcitriol supplementation leads to higher calcium levels, but the high heterogeneity of the included studies (79% to 98.7%) could affect the results.

Early parathyroid hormone (PTH) level as a predictor of post-surgical hypoparathyroidism

INTRODUCTION

Post-operative hypocalcemia and postoperative persistent hypoparathyroidism remain the most common complications after thyroidectomy. Many approaches have been developed to prevent them, but actually, a common protocol is not yet individuated.

MATERIALS AND METHODS

We retrospectively analyzed the results of a prospectively collected database. We dosed PTH preoperatively and 4 h after surgery (PTH_4); calcium was evaluated preoperatively, on the first (I_POD) and on the second postoperative day (II_POD). Hypocalcemia was defined when calcium <8 mg/dl. PTH_4 and I_POD calcium serum levels are identified to predict postoperative hypocalcemia.

RESULTS

Three hundred and forty-eight patients were enrolled, 37 patients resulted as hypocalcemic on I_POD and 41 on the II_POD. PTH_4 is related to I_POD (p < 0.001, r = 0.45) and II_POD (p < 0.001, r = 0.44) calcemia. PTH_4-cut-off predicting I_POD hypocalcemia was 10.50 pg/ml (sensitivity: 78.7%, specificity: 72.7%). A PTH_4 value of 11.5 pg/ml is able to predict hypocalcemia during II_POD (sensitivity: 76.5%, specificity: 69.2%). We set up a combined test to predict II_POD hypocalcemia, using PTH_4 and I_POD calcium (sensitivity: 77.8%, specificity: 89.9%).

CONCLUSION

This research shows the association between PTH_4 and postoperative hypocalcemia. The PTH_4 cut-off to predict I_POD-hypocalcemia was 10.5 pg/ml. We analyzed the calcemia trend during the postoperative period and we realized a combined test using PTH_4 and I_POD-calcemia. This test improves the accuracy of the previous test. Further studies, in particular multicentric, with a larger sample are necessary to validate the combined model.

Clinical outcomes of outpatient thyroidectomy: A systematic review and single-arm meta-analysis

BACKGROUND

The aim of this meta-analysis is to investigate the safety of outpatient thyroidectomy based on 24-h and same-day discharge criteria.

METHODS

CENTRAL, Embase, PubMed, and Scopus were searched. A meta-analysis of selected studies was performed. The review was registered prospectively with PROSPERO (CRD42022361134).

RESULTS

Thirty-one studies met the eligibility criteria, with a total of 74328 patients undergoing thyroidectomy in an outpatient setting based on 24-h discharge criteria. Overall postoperative complications after outpatient thyroidectomies were 5.7% (95%CI: 0.049-0.065; I2 ​= ​97.3%), consisting of hematoma (0.4%; 95%CI: 0.003-0.005; I2 ​= ​83.4%), recurrent laryngeal nerve injury (0.4%; 95%CI: 0.003-0.006; I2 ​= ​93.5%), and hypocalcemia (1.6%; 95%CI: 0.012-0.019; I2 ​= ​93.7%). The rate of readmission was 1.1% (95%CI: 0.007-0.015; I2 ​= ​95.4%). Results were similar for same-day criteria.

CONCLUSIONS

Our analysis demonstrated that outpatient thyroidectomy is a safe procedure in the management of thyroid disease for selected patients.

Serum PTH at 4 h after total thyroidectomy as a predictor of hypocalcemia: a prospective time frame analysis in search of evidence

INTRODUCTION

There has not been a universal agreement about the timings and the threshold level of PTH that can accurately predict the risk of hypocalcemia. Our study aimed to investigate the changes in the serum PTH levels at various time intervals and correlate it with the development of subsequent hypocalcemia.

MATERIALS AND METHODS

All patients had a pre-operative serum PTH done and were again assessed intra-operatively, at 4 h, 24 h, 72 h, and 1 month after the thyroid surgery. Absolute serum PTH value at various time points, absolute change in serum PTH values compared to pre-operative level, and relative change (percentage change) in serum PTH values compared with pre-operative levels were used to predict post-operative Hypocalcemia.

RESULTS

49 patients were included in the study. The sensitivity and negative predictive value was 100% for serum PTH at 4 h. There was a statistically significant difference between the groups that required calcium supplementation versus the group that did not require it. The maximum relative reduction in serum PTH value with respect to the pre-operative level occurred at 4 h in the calcium supplement required group which was 82.5%. Use of combination of 4 h serum PTH and relative change at 4 h yielded the best results.

CONCLUSION

A combination of absolute serum PTH level at 4 h and the relative decline in serum PTH at 4 h has the highest diagnostic accuracy. The use of this combined parameter helps to reliably predict patients who would require supplementation.

Evaluation of an early detection protocol, intensive treatment and control of post-surgical hypoparathyroidism in the first month after total thyroidectomy

BACKGROUND AND OBJECTIVE

Hypoparathyroidism is the most common complication of total thyroidectomy and usually requires monitoring of calcaemia, whereby it is one of the factors that most contributes to hospital stay. The objective of the study is to evaluate the clinical usefulness of the application of our protocol for early detection, intensive treatment and control of hypoparathyroidism in the first month after thyroidectomy.

PATIENTS AND METHOD

Retrospective observational cross-sectional study of 79 patients who underwent total thyroidectomy in whom parathormone (PTH) and calcemia determinations were performed at 6-8 h and 18-24 h post-surgery. When the PTH value was lower than inferior limit of the reference (15 pg/ml), oral treatment was started with 1000 mg of calcium and 0.25 μg of calcitriol every 8 h followed by calcemia controls.

RESULTS

Twenty-six cases (32.9%) of normocalcemic hypoparathyroidism were detected in whom treatment prevented their progression to hypocalcaemia, except for 3 cases that had an episode of mild asymptomatic hypocalcaemia. There were no cases of moderate/severe hypocalcaemia and only one case of asymptomatic mild hypercalcaemia. There were no readmissions due to calcium abnormalities. No case with PTH > 15 pg/ml had hypocalcaemia. The protocol allowed a hospital stay of 24 h. The prevalence of permanent hypoparathyroidism was 5.1%.

CONCLUSIONS

The application of our protocol during the first month after thyroidectomy is very useful because it avoids the appearance of moderate/severe hypocalcaemia and hypercalcaemia, allows a short hospital stay and is associated with a low prevalence of permanent hypoparathyroidism.

Parathyroid hormone-driven algorithms after thyroid surgery: Not one-size-fits-all

BACKGROUND

Underreported variation in parathyroid hormone (PTH) assays exists. Using quality improvement methods, we aimed to develop an institution-specific PTH-based protocol to predict hypocalcemia after thyroidectomy.

METHODS

We retrospectively reviewed patients who underwent total/completion thyroidectomy. A receiver operating curve (ROC) determined postoperative PTH cut-offs predictive of hypocalcemia. The stakeholders developed PTH-driven calcium management guidelines. Post-implementation outcomes were prospectively measured.

RESULTS

Pre-implementation, 95 patients were assessed. PTH ≤1.5 pmol/L (14.1 pg/ml) predicted hypocalcemia (96%sensitivity), and ≥2.8 pmol/L (26.4 pg/ml) predicted normocalcemia (99%specificity) (area under curve = 0.97, SEM = 0.018). PTH on the day of and morning after surgery were identically predictive. Post-implementation, 64 patients were assessed. Hypocalcemia occurred with PTH >2.8 pmol/L in 2 cases (3.1%). Calcium over-prescribing decreased from 13.7% to 3.1% (p = 0.06). Length of stay (LOS) > 2 nights decreased from 13% to 3.1% (p = 0.05).

CONCLUSION

A PTH-driven calcium management protocol post-thyroidectomy effectively reduces unnecessary calcium replacement and LOS. Given the variability in PTH assays, each institution may need to use individual cut-offs.

A Parathyroid Hormone-guided Calcium and Calcitriol Supplementation Protocol Reduces Hypocalcemia-related Readmissions Following Total Thyroidectomy

OBJECTIVE

To determine the effect of a 4 hour postoperative serum parathyroid hormone (PTH) guided calcium and calcitriol supplementation protocol on the incidence of hypocalcemia and hospital readmissions in patients undergoing total thyroidectomy.

METHODS

This was a single institution, retrospective chart review of patients who underwent total thyroidectomy, 148 had been operated on prior to the protocol implementation and 389 after. Hypocalcemia risk was stratified as low (PTH >30 pg/ml), medium (15-30 pg/ml), and high (<15 pg/ml), using serum PTH values obtained 4 hours postoperatively. Hypocalcemia was defined as a total serum calcium level <8 mg/dl. Baseline demographic and operative characteristics, and postoperative outcome were recorded for both groups. Fisher's exact test or Wilcoxon rank sum test were used to compare the characteristics of the two groups. A multivariable logistic regression model was applied to account for potentially confounding variables.

RESULTS

Postoperative hypocalcemia occurred significantly less frequently in the protocol group compared to the preprotocol group (10.3% vs. 20.9%, P=.002). The reduction in hypocalcemia in the protocol group was observed both in patients with (16.3% vs. 25.6%) and without (8.4% vs. 19.3%) cervical lymph node dissection. There was a significantly lower incidence of hospital readmission events in the protocol group compared to the preprotocol group (1.0% vs. 4.7%, P=.013).

CONCLUSIONS

Compared to a historical cohort, a PTH-guided protocol for calcium and calcitriol supplementation significantly reduces postoperative hypocalcemia and hospital readmission rates, in patients undergoing total thyroidectomy.

Definition and diagnosis of postsurgical hypoparathyroidism after thyroid surgery: meta-analysis

Background

Postsurgical hypoparathyroidism (PH) is the most frequent complication after thyroid surgery. The aim of this systematic review and meta-analysis is to summarize a unifying definition of PH and to elucidate the best possible approach for early detection of PH.

Methods

A systematic review of the literature according to the PICO framework using Embase, PUBMED and the Cochrane library was carried out on 1 December 2021 followed by analysis for risk of bias, data extraction and meta-analysis. All studies addressing the definition of postoperative hypoparathyroidism and/or diagnostic approaches for early detection and diagnosis were included. Case reports, commentaries, non-English articles, book chapters and pilot studies and reviews were excluded.

Results

From 13 704 articles, 188 articles were eligible for inclusion and further analysis. These articles provided heterogeneous definitions of PH. Meta-analysis revealed that postoperative measurements of parathormone (PTH) levels have a higher sensitivity and specificity than intraoperative PTH measurements to predict PH after thyroid surgery. None of the timeframes analysed after surgery within the first postoperative day (POD1) was superior to predict the onset of PH. PTH levels of less than 15 pg/ml and less than 10 pg/ml are both reliable threshold levels to predict the postoperative onset of PH. A relative reduction of mean(s.d.) PTH levels from pre- to postoperative values of 73 (standard deviation 11) per cent may also be predictive for the development of PH. The estimation of calcium levels on POD1 are recommended.

Conclusion

PH is best defined as an undetectable or inappropriately low postoperative PTH level in the context of hypocalcaemia with or without hypocalcaemic symptoms. PTH levels should be measured after surgery within 24 h. Both threshold levels below 10 and 15 pg/ml or relative loss of PTH before/after thyroid surgery are reliable to predict the onset of PH.

Change in parathyroid hormone levels from baseline predicts hypocalcemia following total or completion thyroidectomy

BACKGROUND

This study aims to identify the strongest predictor of postoperative hypocalcemia following thyroid surgery.

METHODS

Study of patients who underwent total/completion thyroidectomy. No patients received postoperative calcium supplementation. Demographic and perioperative data were collected including preoperative baseline parathyroid hormone (PTH) levels, PTH levels at 30 min and 6 h post-excision, and 18 h post-excision calcium levels.

RESULTS

Of 124 patients studied, 20.2% developed temporary hypocalcemia (Ca <8.5 mg/dL at 18 h post-excision). In multivariate analyses, absolute PTH levels at 30 min and 6 h post-excision as well as change in PTH from baseline at 30 min and 6 h post-excision were statistically significantly associated with postoperative hypocalcemia. Per 10 units decrease in PTH from baseline at 30 min post-excision, the risk of developing temporary hypocalcemia increases by 17%.

CONCLUSION

Absolute PTH levels and change in PTH from baseline at 30 min and 6 h post-excision predict hypocalcemia after total or completion thyroidectomy.

Predictive value of postoperative day 1 parathyroid hormone levels for early and late hypocalcaemia after thyroidectomy

PURPOSE

Early parathyroid hormone (PTH) levels after total thyroidectomy can predict patients at low risk of hypocalcaemia who can be discharged early without calcium supplementation. For centres without facility to perform early PTH levels, PTH levels sent on the first postoperative day (POD1) may be an alternative. However, there is less data regarding optimal cut-off PTH levels for POD1 discharge.

METHODS

Retrospective review of prospective database of thyroid operations between September 2009 and February 2020 at tertiary referral centre. Main outcome measure was symptomatic hypocalcaemia.

RESULTS

Five hundred seventy patients undergoing total (521) or completion thyroidectomy with POD1 PTH levels available were included. Among patients with POD1 PTH levels ≥ 20 pg/ml and POD1 calcium ≥ 2.0 mmol/l, the incidence of symptomatic hypocalcaemia was 1% (3/300), and need for intravenous calcium 0.3% (1/300). For POD1 PTH levels 15-19 pg/ml and POD1 calcium ≥ 2.0 mmol/l, the incidence of symptomatic hypocalcaemia and need for intravenous calcium was 5.4% (3/55). For PTH levels 10-14 pg/ml and calcium ≥ 2.0 mmol/l, the incidence of symptomatic hypocalcaemia and need for intravenous calcium was 11.7% (7/60). The risk of permanent hypoparathyroidism was < 1% for POD1 PTH levels ≥ 15 pg/ml; 5.4% for levels 10-14 pg/ml; and 19.8% for levels < 10 pg/ml.

CONCLUSIONS

POD1 PTH levels ≥ 15 pg/ml along with calcium ≥ 2.0 mmol/l are associated with low risk of symptomatic hypocalcaemia, and represent a safe criterion for discharge of most patients without calcium supplementation. For certain patient groups, a higher threshold of 20 pg/ml could be considered.

Risk of Hypocalcemia and the Need to Augment Calcium Supplementation After Total Thyroidectomy

Hypocalcemia is the most common complication after total thyroidectomy. The aim of this study was to determine the predictors of postoperative hypocalcemia requiring augmentation of routine calcium supplementation. Prospectively collected data of 61 patients who underwent total thyroidectomy from December 2018 to June 2019 was considered for the study. All patients received calcium and vitamin D supplementation after the surgery. In the postoperative period, serum calcium and parathormone (PTH) levels were monitored. The need of additional oral or intravenous (i.v.) calcium supplementation was evaluated as an outcome measure. This cohort comprised 61 patients with median age of 46 years (range 16-80 years) and 49 (80%) females. Central compartment clearance (CCC) was done in 32 patients. Escalation to increased oral and intravenous calcium was required in 15 patients (24.6%) and 2 patients (3.3%), respectively. Serum parathormone level of 11.5 pg/ml on postoperative day 1 predicted the requirement of additional calcium with a sensitivity of 82.4% and specificity of 77.3%. On univariate analysis, serum PTH (p < 0.001), CCC (p = 0.018), and intraoperative parathyroid gland congestion (p = 0.021) predicted the need for escalation of calcium supplementation. On multivariate analysis, only serum PTH showed a significant impact on the need for augmentation of calcium supplementation (p = 0.003). The need for calcium dose augmentation after total thyroidectomy was significantly associated with CCC, parathyroid gland congestion, and serum PTH levels. Intraoperative identification of parathyroid gland congestion and postoperative serum PTH levels is effective in predicting postoperative hypocalcemia with implications on time and cost.

Role of postoperative intact serum PTH as an early predictor of severe post-thyroidectomy hypocalcemia: a prospective study

BACKGROUND

Post thyroidectomy hypocalcemia is a major sequel of thyroidectomy and continues to trouble the endocrinologists and the endocrine surgeons as there is no ideal predictive marker of hypocalcemia which has the potential to develop into a life-threatening complication. The role of early serum intact parathormone (iPTH) to predict post thyroidectomy hypocalcemia is becoming useful but the literature is still unclear regarding the optimal time of testing and the optimal cut-off value of serum iPTH.

PATIENTS AND METHODS

This is a prospective cohort study of 111 patients who underwent total thyroidectomy in a tertiary care endocrine surgery referral unit. Serum iPTH was measured after 20 min and 4 h of surgery. Receiver-Operator characteristic Curve (ROC) was used to find out of the best cut-off value of S. iPTH 20 min and 4 h after surgery in predicting hypocalcemia.

RESULTS

Hypocalcemia was noted in 60 (54%) out of 111 subjects who underwent total thyroidectomy. The best cut-off values of Serum iPTH to predict hypocalcemia was found to be 4.28 pmol/l at 20 min post total thyroidectomy with a sensitivity and specificity of 81.7% and 51%, respectively. In addition, patients with malignancy or central lymph nodal dissection were significantly over-represented in the hypocalcemia group with serum iPTH above the threshold level of 4.28 pmol/l. Below the cut off level, parenteral calcium supplementation was required in 23% (17/74) subjects while the rate was only 5.4% (2/37) patients when serum iPTH was above the cut-off level.

CONCLUSIONS

The decline of serum iPTH below a specific level after surgery has predictive value together with other factors strictly related to patient, the thyroid disease itself and surgery. The risk of development of hypocalcemia and consequent need for calcium supplementation should be evaluated by clinical assessment along with serum PTH measurement.

Role of perioperative parathormone hormone level assay after total thyroidectomy as a predictor of transient and permanent hypocalcemia: Prospective study

Background

The researchers are trying to evaluate the measurement of: Intact parathyroid hormone (iPTH) and serum total calcium (sCa) levels for predicting hypocalcemia after total thyroidectomy (TT).

Methods

The sample of this single center prospective study consists of (100) patients, where (77) females and (23) males with an age range between (28) and (65) (the mean level is, 48.17 ± 6.54). These selected patients underwent total thyroidectomy (TT) in the general surgery department, Benha university hospital from the period of June 2019 to February 2020. Levels of sCa and iPTH were measured aat several times preoperatively, 10 min, 48 h, 3, 6, 9 months, and 1 year after being after gone TT.

Results

Among the entire study sample, 23 patients (23%) developed transient hypoparathyroidism and hypocalcemia (˂8.5 mg/dl), none of them developed permanent hypoparathyroidism and hypocalcemia. The cut-off point of PTH has been 10 min after TT was at 23 pg/mL as it was the best compromise between sensitivity and specificity for predicting hypocalcaemia. It has been found that Patients who have a PTH greater than 23 pg/mL can be discharged safely after 24 h. Patients who have PTH of less than 23 pg/mL were observed for an additional 24 h, and the study found that timely treatment initiation is recommended. A PTH ˂ 10 pg/mL measured at 48 h after surgery had a sensitivity, specificity as well as an accuracy of 100%, for predicting hypocalcemia after TT. The accuracy of a single PTH concentration at 48 h was useful for predicting hypocalcemia [Area under receiver–operator characteristic curve (AUC) 1; confidence interval (CI), 95%, 0.85–0.94].

Conclusion

Patients with iPTH ˂ 10 pg/mL, and sCa levels ˂ 7.4 mg/dL are at higher risk of developing hypoparathyroidism and hypocalcemia after TT.

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Incidence of Post-thyroidectomy transient hypoparathyroidism ranges between 0.3 and 49%, while permanent hypoparathyroidism is 13%.

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Incidence of hypocalcemia following total thyroidectomy ranging between 3% and 40% and is usually transient, while permanent hypocalcemia is ≤ 2%.

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Post-thyroidectomy PTH accurately predict hypocalcemia.

Measurement of serum intact parathyroid hormone concentration 1 day after total thyroidectomy to assess risk of permanent hypoparathyroidism

OBJECTIVE

This study was performed to assess the clinical value of measuring the intact parathyroid hormone (iPTH) concentration 1 day after total thyroidectomy to estimate the occurrence of permanent hypoparathyroidism (pHPP).

METHODS

Data of 546 patients who underwent total thyroidectomy from February 2008 to December 2018 were retrospectively analyzed. Calcium and iPTH concentrations were collected preoperatively and at 1 day and 6 months postoperatively. Logistic regression was used to analyze the correlation between clinical indexes and postoperative pHPP.

RESULTS

Of the 546 patients, 22 (4.03%) developed pHPP. Multivariate analysis showed that the iPTH and serum calcium concentrations measured 1 day after surgery were independent predictors of the risk of pHPP. An iPTH concentration of 5.51 pg/mL measured 1 day postoperatively was used as the cut-off value, and the area under the curve was 0.956. The risk of pHPP was identified with a sensitivity of 100%, specificity of 85.1%, positive predictive value of 22%, and negative predictive value of 100%.

CONCLUSIONS

The iPTH concentration measured 1 day after total thyroidectomy is closely related to the occurrence of pHPP postoperatively and is an independent predictive risk factor. The postoperative iPTH concentration can be helpful in identifying patients at risk for developing pHPP.

[Postoperative hypocalcemia - the most common complication of endocrine head and neck surgery: acute management]

BACKGROUND

In Germany, 8000 patients are affected by postoperative hypoparathyroidism per year following surgery of the thyroid gland, parathyroidal glands and the larynx. Patients do not only suffer from paresthesia in the acute phase of this complication, but are also adversely affected by the fear of loss of control following episodes of tetany even years after the first episode.

OBJECTIVES

Discussion of a diagnostic pathway and presentation of a management pathway for postoperative hypocalcemia.

METHODS

Narrative review, analysis and discussion of current literature and expert recommendations.

RESULTS

Early determination of calcium and parathyroid hormone allows timely diagnosis and treatment of postoperative hypoparathyroidism. Active vitamin D is pivotal for the resorption of calcium. Only the combined treatment with active vitamin D and calcium can mitigate or prevent the postoperative drop of calcium levels.

CONCLUSIONS

A standard operating procedure (SOP) for postoperative hypoparathyroidism should be implemented in every surgical department. An SOP for diagnosis and treatment of postoperative hypoparathyroidism is proposed for institutional individualization and implementation.

Therapeutic Plasma Exchange in Refractory Hyperthyroidism

INTRODUCTION

Hyperthyroid patients who are unresponsive to medical treatment remain a challenging clinical problem.

OBJECTIVE

The goal of our study was to evaluate the use of therapeutic plasma exchange (TPE) in hyperthyroid patients and their outcome after TPE.

METHOD

We retrospectively reviewed 22 patients who underwent TPE for refractory thyrotoxicosis in our institution: 13 with Graves' disease, 7 with amiodarone-induced thyrotoxicosis (AIT), 1 with toxic goiter, and 1 pregnant patient with familial nonautoimmune thyrotoxicosis.

RESULTS

Before TPE, all patients had severe hyperthyroidism, and antithyroid drugs were either contraindicated or not sufficiently effective to restore euthyroidism promptly. After all the TPEs, free T₄ (fT4) decreased significantly by 48% (p = 0.001) and fT3 by 52% (p = 0.0001). The median number of TPE sessions per patient was 4 (range: 1-10). There were no complications during the 91 TPE sessions. Total thyroidectomy with no severe side effects was performed on 16/22 patients and 1 other patient was treated with radioactive iodine. One patient died from severe thyrotoxicosis during medical care. The remaining 4 patients were followed up without any radical treatment. For all 7 patients with AIT, iterative TPE led to a significant clinical improvement, and amiodarone was continued for 1 patient. Available treatments were continued between TPE sessions (cholestyramine for 13 patients [60%] and glucocorticoids for 16 patients [73%]).

CONCLUSION

TPE allowed a safe decrease of 50% in thyroid hormone levels, and it should be considered for refractory hyperthyroid patients when medical treatments are contraindicated or have failed to restore euthyroidism, irrespective of the etiology of the thyrotoxicosis.

A Meta-Analysis of Risk Factors for Transient and Permanent Hypocalcemia After Total Thyroidectomy

Background

As hypocalcemia is the most common complication of total thyroidectomy, identifying its risk factors should guide prevention and management. The purpose of this study was to determine the risk factors for postthyroidectomy hypocalcemia.

Methods

We searched PubMed, Web of Science and EMBASE through January 31, 2019, and assessed study quality using the Newcastle–Ottawa Scale.

Results

Fifty studies with 22,940 patients met the inclusion criteria, of which 24.92% (5716/22,940) had transient hypocalcemia and 1.96% (232/11,808) had permanent hypocalcemia. Significant (P < 0.05) predictors of transient hypocalcemia were: younger age, female, parathyroid autotransplantation (PA), inadvertent parathyroid excision (IPE), Graves’ disease (GD), thyroid cancer, central lymph node dissection, preoperative severe Vitamin D deficiency, preoperative Vitamin D deficiency and a lower postoperative 24 h parathyroid hormone (PTH) level. Preoperative magnesium, preoperative PTH and Hashimoto’s thyroiditis were not significant predictors of transient hypocalcemia. IPE, GD, and thyroid cancer were associated with an increased rate of permanent hypocalcemia, but gender and PA did not predict permanent hypocalcemia.

Conclusion

Important risk factors for transient and permanent hypocalcemia were identified. However, given the limited sample size and heterogeneity of this meta-analysis, further studies are required to confirm our preliminary findings.

Tiempo óptimo para medición de paratohormona como predictor de hipocalcemia en pacientes posterior a tiroidectomía total

Introducción. La hipocalcemia posterior a tiroidectomía total es una complicación frecuente en la cirugía de tiroides. La hormona paratiroidea ha demostrado ser un predictor confiable para detectar los pacientes con alto riesgo de hipocalcemia significativa y la consecuente necesidad de administrar suplemento de calcio. El objetivo de este estudio fue determinar el tiempo óptimo de medición de la paratohormona para dicho fin. Métodos. Estudio prospectivo realizado en dos instituciones de nivel III en Popayán, Colombia, entre abril de 2016 y febrero de 2018, en el cual se midieron niveles de paratohormona prequirúrgico, a las 0, 2, 4 y 12 horas del postoperatorio, y se compararon con los valores obtenidos a los 3 meses de seguimiento en pacientes sometidos a tiroidectomía total. Se consideró como grupos de riesgo y con necesidad de suplemento de calcio un valor de paratohormona menor de 10 pg/ml o una disminución mayor del 80 % con respecto al valor prequirúrgico. Resultados. Se incluyeron 34 pacientes intervenidos. Tomando como umbral un valor menor de 10 pg/ml, la medición de paratohormona a las 4 horas fue sensible y específica (60 y 93,1 % respectivamente). Para una disminución mayor del 80 % con respecto al valor prequirúrgico, la sensibilidad fue del 60 % y la especificidad del 96,5 %, presentando un valor predictivo positivo de 75 % y negativo del 93,3 %, con una p < 0,001. Discusión. Una disminución mayor del 80 % del valor de paratohormona prequirúrgico medida a las 4 horas después de la tiroidectomía total permite identificar aquellos pacientes con alto riesgo de hipocalcemia significativa, que requieren administración temprana de suplementos de calcio, comparado con la determinación de la disminución a las 0, 2 y 12 horas postoperatorias.

EARLIER PREDICTION OF HYPOCALCEMIA BY POSTOPERATIVE SECOND HOUR PARATHYROID HORMONE LEVEL AFTER TOTAL THYROIDECTOMY

Context

Thyroidectomy is becoming an ambulatory surgical procedure. By predicting hypocalcemia,duration of hospital stay might decline. We tried to determine whether measuring parathormone two hours after total thyroidectomy predicts hypocalcemia.

Objective

We aimed to design a protocol for early prediction of hypocalcemia by defining PTH measurement time and cut-off value of our center.

Design

One hundred and six patients undergoing total thyroidectomy between November 2017 and October 2018 were prospectively studied.

Methods

Pregnant women, patients with renal failure, parathyroid disease, previous neck operation and thyroid malignancy requiring neck dissection were excluded from the study. Parathormone (PTH) and calcium measurement was done preoperatively and in the postoperative second hour.

Results

Group 1 consisted of 75 normocalcemic patients while group 2 had 31 hypocalcemic patients. Mean age was 45±13.1 (age range: 18-76). Female/male ratio was 82/24. While with a 8.36 pg/mL postoperative second hour PTH, hypocalcemia can be predicted with a 51.5% sensitivity and 90.7% specificity while with a PTH decline of 40.8% hypocalcemia can be diagnosed with a 83.9% sensitivity and 52% specificity.

Conclusion

Postoperative second hour PTH and PTH percentage decline can predict postoperative hypocalcemia in total thyroidectomies. Preoperative Dual-energy X-ray absorptiometry (DXA) was not found useful in hypocalcemia prediction.

Parathormone decline levels are better markers of symptomatic hypocalcemia following total thyroidectomy than parathormone alone

Background: We aimed to assess the predictive value of the absolute and relative intact parathormone (iPTH) decline levels as reliable markers of postoperative hypocalcemia. Materials & methods: iPTH levels were measured 4 h after surgery and the following morning after surgery (postoperative day 1). iPTH, absolute iPTH decline (ΔPTH) and relative iPTH decline (ΔPTH%) were calculated and correlated with symptomatic hypocalcemia. Results: Of the 95 patients, 20% of patients (n = 19) developed symptomatic hypocalcemia. The ΔPTH (U = 206; p < 0.001) and ΔPTH% (U = 127; p < 0.001) were significantly higher in patients with symptomatic hypocalcemia. A ΔPTH% of 20% (sensitivity of 84%; specificity of 91%); and an absolute iPTH decline of 3.75 pg/ml (sensitivity of 74%; specificity of 87%) were highly predictive of symptomatic hypocalcemia. Conclusion: Postoperative ΔPTH and ΔPTH% have the potential to be predictors of symptomatic hypocalcemia following thyroidectomy and could facilitate a safe early discharge.

Predicting Postthyroidectomy Hypocalcemia: Improving Predictive Ability of Parathyroid Hormone Level

We performed a retrospective study of our large patient cohort aiming to examine the ability to predict postthyroidectomy hypocalcemia. A retrospective review of patients who underwent total or near-total thyroidectomy at our institution between 2008 and 2018 was performed. Postoperative hypocalcemia was defined as Ca level <8.0 mg/dL (reference range: 8.9–10.1 mg/dL) within 30 days of operation. Logistic regression was used to develop models for prediction of the occurrence of postoperative hypocalcemia. Inclusion criteria were met by 1463 patients. Hypocalcemia was documented in 223 patients (15%). Models based on parathyroid hormone (PTH) levels alone had an associated receiver operator characteristic with an areas under the curve (AUC) of 0.79. There was an inverse relationship between time of measurement and PTH levels within the first two hours after thyroidectomy ( P < 0.01). When measured two to six hours after closure, the predictive ability of PTH compared favorably (AUC = 0.82) with either earlier (within the first two hours after closure, AUC = 0.79) or later measurement (6–24 hours after closure, AUC = 0.77). When measured between two and six hours postoperatively, PTH < 19 pg/mL had a sensitivity of 90 per cent and negative predictive value of 96 per cent for postoperative hypocalcemia. The model that included the PTH level, concurrently measured total blood calcium level, and time of measurement had an improved predictive ability with an AUC of 0.87. PTH level of 19 pg/mL measured two to six hours after thyroidectomy had a sensitivity of 90 per cent and a negative predictive value of 96 per cent in our cohort. The model including postoperative PTH level, calcium level, and time of measurement may further improve the ability to predict postthyroidectomy hypocalcemia.

Combined ionized calcium and PTH evaluation in the management of post-thyroidectomy hypocalcemia

BACKGROUND

The aim of our study was to investigate the postoperative course of calcium and parathyroid hormone (PTH) levels after total thyroidectomy to define a proper and low cost protocol.

METHODS

We studied 144 patients who underwent total thyroidectomy between 2007 and 2010. Ionized calcium was determined preoperatively and on day 1 (POD1), day 2 (POD2) and day 7 (POD7) postoperatively; PTH preoperatively and on POD7. Patients with ionized calcium ≤1.11 mmol/L were considered hypocalcemic and treated only if symptoms, ≤1 mmol/L were treated in all cases.

RESULTS

Ionized calcium and PTH declined postoperative in all patients compared to preoperative levels (P=0.000). Ionized calcium increased on POD7 compared to POD1 and POD2 (P=0.000). All hypocalcemic untreated 30 patients returned normocalcemic on POD7. Thirty-eight hypocalcemic patients were treated but 23 (61%) safely suspended therapy on POD7. We tested PTH and ionized calcium as independent factors of prolonged hypocalcemia (that required therapy beyond 7 days) with the following results (sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy): PTH ≤11 pg/mL (80%, 100%, 100%, 96% and 97%, respectively), ionized calcium ≤1.11 mmol/L (80%, 88%, 59%, 95%, and 87%, respectively) and ionized calcium ≤1 mmol/L (28%, 100%, 100%, 87% and 88%, respectively).

CONCLUSIONS

Our data show that our protocol, including serum ionized calcium on 1^st, 2^nd, 7^th days and PTH on 7^th day after surgery, is safe and low cost and therefore may be useful in the post-surgical management of total thyroidectomy.

Critical Care and Postoperative Management of the Head and Neck Patient

Head and neck surgical patients, at times, can represent a challenging population to manage in the intensive care unit postoperatively. Close interaction between the critical care and surgical teams, awareness of potential surgery-specific complications, and utilization of protocol-driven care can reduce risk of morbidity significantly in this population and enhance outcomes. Given the relative complexity of otolaryngologic surgery and the unique risk that head and neck pathologies can pose to patient airway, breathing, and circulation, these collective circumstances warrant detailed discussion in the interest of minimizing patient morbidity and mortality.

A Single Parathyroid Hormone Measurement Two Hours after a Thyroidectomy Reliably Predicts Permanent Hypoparathyroidism

INTRODUCTION

Hypoparathyroidism is the most common complication following thyroidectomy, and various algorithms for early detection have been suggested. The aim of this study was to evaluate the predictive value of measuring the parathyroid hormone level 2 h after thyroidectomy and whether determination of the perioperative decline in parathyroid hormone added diagnostic value.

METHODS

Patients subjected to thyroidectomy for benign thyroid disorders were analyzed in (1) a retrospective register-based study (366 consecutive patients treated during 2015-2016) and (2) a prospective observational study (39 patients treated during 2018). Optimal cut-off values for postoperative parathyroid hormone and perioperative decline (%) in parathyroid hormone were determined by receiver operating characteristics and area under the curve. Sensitivity, specificity, positive and negative predictive values were calculated using cross tabulation.

RESULTS

The prevalence of hypoparathyroidism the first day after thyroidectomy was higher among patients treated for hyperthyroidism (30% vs 20%; P = 0.03). The optimal cut-off level for postoperative parathyroid hormone was 1.1 pmol/L (area under the curve = 0.887, 95% confidence interval: 0.839-0.934; positive predictive value: 88%, negative predictive value: 93%) for the entire cohort. When the groups were analyzed separately, the optimal cut-off was 1.05 for the non-hyperfunctioning group and 1.55 pmol/L for the group with hyperthyroidism. Twelve months after thyroidectomy, 3% were defined as having permanent hypoparathyroidism. Measurement of parathyroid hormone decline added diagnostic value for one patient with preoperative parathyroid-hormone-elevation associated with vitamin D deficiency.

CONCLUSION

For patients with vitamin D sufficiency, the diagnostic accuracy of a single measurement of parathyroid hormone 2 h after thyroidectomy is an excellent indicator for predicting transient hypoparathyroidism.

Cost-effectiveness in transient hypocalcemia post-thyroidectomy

BACKGROUND

Three different strategies to manage transient hypocalcemia after total thyroidectomy were compared to evaluate cost-effectiveness. The reliability of total serum calcium (TSCa), ionized calcium (ICa), and intact parathyroid hormone (iPTH) were investigated to achieve this goal.

METHODS

A multicenter, prospective randomized study was carried out with 169 patients. The strategies were "preventive" (oral calcium + vitamin D supplementation), "reactive" (therapy in hypocalcemia), and "predictive" (therapy if iPTH <10 pg/mL).

RESULTS

TSCa had higher accuracy in identifying patients who developed hypocalcemia-related symptoms than ICa (84.6% vs 50.0%). TSCa 24 h after surgery showed 24.8% of patients with hypocalcemia, whereas TSCa 48 h after surgery identified a further 10.6% with hypocalcemia (only in the "reactive" and "predictive" groups). iPTH showed low sensitivity as a predictor of hypocalcemia. Between the 3 groups, there was no significant difference in hospitalization time or number of symptomatic hypocalcemic patients. Interestingly, the cost-per-patient was significantly different among the groups.

CONCLUSIONS

None of the discussed strategies allowed for early discharge of patients without any risk of transient hypocalcemia. The "preventive" strategy was the most cost-effective, despite overtreatment.

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.

One-Hour Postoperative Parathyroid Hormone Levels Do Not Reliably Predict Hypocalcemia After Thyroidectomy

INTRODUCTION

Hypocalcemia is a well-known complication after total thyroidectomy. Studies have indicated that the presence of low postoperative parathyroid hormone (PTH) levels can predict hypocalcemia. However, definitive study designs are lacking. The aim of this study was to determine whether postoperative PTH alone can accurately predict postoperative biochemical hypocalcemia.

METHODS

Under IRB approval, a prospective study of 218 consecutive patients who underwent total or completion thyroidectomy by two surgeons between June 2014 and June 2016 was performed. Biochemical hypocalcemia was defined as ionized calcium <1.13 mmol/L or serum calcium <8.4 mg/dL at any time postoperatively. Three PTH thresholds, <10, <20 pg/mL, and >50% drop in PTH 1 h postoperatively from baseline were examined.

RESULTS

Postoperative PTH < 10 pg/mL had a sensitivity of 36.5% (95% CI 27.4-46.3%) and a specificity of 89.2% (95% CI 81.9-94.3%). Postoperative PTH < 20 pg/mL had a sensitivity of 66.4% (95% CI 56.6-75.2%) and a specificity of 67.6% (95% CI 58.0-76.2%). Postoperative PTH decrease >50% had a sensitivity of 63.4% (95% CI 53.2-72.7%) and a specificity of 72.5% (95% CI 62.5-81.0%). Across all PTH thresholds, the false-negative rate was 33.6-63.5% indicating that up to 64% of patients with a normal PTH level could have been discharged without appropriate calcium supplementation. The false-positive rate was 10.8-32.4% indicating that up to 32.4% of patients with low PTH could have been treated with calcium supplementation unnecessarily.

CONCLUSION

Following total thyroidectomy, PTH levels are unreliable in predicting hypocalcemia. Additional prospective studies are needed to understand the true utility of PTH levels post-thyroidectomy.

American Thyroid Association Statement on Postoperative Hypoparathyroidism: Diagnosis, Prevention, and Management in Adults

BACKGROUND

Hypoparathyroidism (hypoPT) is the most common complication following bilateral thyroid operations. Thyroid surgeons must employ strategies for minimizing and preventing post-thyroidectomy hypoPT. The objective of this American Thyroid Association Surgical Affairs Committee Statement is to provide an overview of its diagnosis, prevention, and treatment.

SUMMARY

HypoPT occurs when a low intact parathyroid hormone (PTH) level is accompanied by hypocalcemia. Risk factors for post-thyroidectomy hypoPT include bilateral thyroid operations, autoimmune thyroid disease, central neck dissection, substernal goiter, surgeon inexperience, and malabsorptive conditions. Medical and surgical strategies to minimize perioperative hypoPT include optimizing vitamin D levels, preserving parathyroid blood supply, and autotransplanting ischemic parathyroid glands. Measurement of intraoperative or early postoperative intact PTH levels following thyroidectomy can help guide patient management. In general, a postoperative PTH level <15 pg/mL indicates increased risk for acute hypoPT. Effective management of mild to moderate potential or actual postoperative hypoPT can be achieved by administering either empiric/prophylactic oral calcium and vitamin D, selective oral calcium, and vitamin D based on rapid postoperative PTH level(s), or serial serum calcium levels as a guide. Monitoring for rebound hypercalcemia is necessary to avoid metabolic and renal complications. For more severe hypocalcemia, inpatient management may be necessary. Permanent hypoPT has long-term consequences for both objective and subjective well-being, and should be prevented whenever possible.

Hypocalcemia after thyroidectomy: iPTH levels and iPTH decline are predictive? Retrospective cohort study

Background

Hypocalcemia is the most common complication of thyroid surgery. The aim of this study was to determine the early predictive factors of postoperative hypocalcemia and to analyze their efficiency.

Methods

We performed a retrospective study of 345 consecutive patients who underwent total thyroidectomy at the Endocrine Surgery Department (Policlinico G. Rodolico Hospital of Catania) between January 2011 and November 2013. We measured serum intact parathormone (iPTH) levels preoperatively and 4 h after surgery. The threshold values of hypocalcemia for iPTH levels and iPTH relative decline were obtained by receiver operating curves (ROC) analysis.

Results

The incidence of hypocalcemia was 32.2% (111 of 345 patients). Our statistical analysis revealed that hypocalcemia rate was strongly correlated with the lower iPTH values and greater iPTH decline (P < 0.001). The threshold enabling prediction of hypocalcemia were 12,5 pg/mL for iPTH and 55,7% for relative iPTH decline. Patients with iPTH <12,5 pg/mL developed hypocalcemia in 58.6% of cases while those with iPTH ≥12,5 pg/dl in 18.8%. Among 175 patients with iPTH relative decline greater than 55,7% hypocalcemia was diagnosed in 91 cases (52%), while other 170 patients with iPTH relative decline less than 55,7% developed hypocalcemia only in 20 cases (11,7%).

Conclusions

The decreased iPTH levels and increased iPTH relative decline resulted to be an accurate predictive factors of postoperative hypocalcemia. The early administration of Calcium and vitamin D in the high-risk patients should be put on in order to prevent the symptoms of hypocalcemia and to reduce the costs and duration of hospitalization.

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Predictive factors of postoperative hypocalcemia.

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Retrospective study of 345 patients.

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The threshold were iPTH 12,5 ng/L and iPTH decline 55,7%.

The role and timing of parathyroid hormone determination after total thyroidectomy

Postoperative hypocalcemia is a common complication of total thyroidectomy resulting from manipulation, resection, or devascularization of the parathyroid glands. Parathyroid hormone (PTH) levels assessed in the perioperative period have been used to predict development of hypocalcemia. Articles examining the role of PTH measurement in the perioperative period following total or completion thyroidectomy are reviewed. Focus is placed on the timing of PTH measurement and the ability to predict which patients will develop hypocalcemia requiring supplementation. Postoperative PTH determination is highly accurate in predicting the development of hypocalcemia. Studies have examined PTH levels drawn at differing time points, ranging from intraoperatively until postoperative day 1 (POD1) with similar accuracy. This data is used to guide postoperative selective calcium and calcitriol supplementation in patients at highest risk for hypocalcemia. When evaluated within the first 4 hours postoperatively, predictive accuracy is maintained but can allow for earlier discharge for those patients at lower risk. Alternatively, some authors argue for routine supplementation, which can reduce the rate of postoperative hypocalcemia but increases the rate of unnecessary supplementation and potential risks associated with hypercalcemia. PTH determination at four hours after total thyroidectomy is an accurate predictor of hypocalcemia and can guide selective calcium supplementation for those at high risk, as well as facilitate a safe earlier hospital discharge for those at low risk of developing postoperative hypocalcemia.

The Impact of Postoperative Percent Change of Parathormone Level From Baseline Value on the Rate of Hypocalcemia After Total Thyroidectomy

Background

The purpose of this study was to investigate the impact of the percent change of postoperative parathormone (PoPTH) level from baseline value (ΔPTH) on the rate of hypocalcemia after total thyroidectomy.

Methods

Assays of serum PTH and calcium (Ca) were performed preoperatively and at 24 hours postoperatively in 222 consecutive patients who underwent total thyroidectomy. Postoperative hypocalcemia was defined as serum calcium level corrected for albumin concentration (cCa) &lt;8.5 mg/dL. Patients with postoperative hypocalcemia were classified as group 1 (n = 100) and those with normal Ca levels as group 2 (n = 122). The PoPTH levels and ΔPTH were compared between the 2 groups. Receiver operating characteristic analysis was performed to determine the cutoff values for PoPTH and ΔPTH.

Results

The mean PoPTH level was significantly lower in group 1 compared with group 2 (18.6 ± 15.3 versus 32.3 ± 15.6 pg/mL, respectively; P &lt; 0.0001). PoPTH values were within the normal range in 54% of the patients with hypocalcemia and 35% of those with symptomatic hypocalcemia. PoPTH &lt;28 pg/mL or ΔPTH &gt;45 were significantly associated with increased risk of post-thyroidectomy hypocalcemia (P = 0.0001). A ΔPTH &gt;70%, PoPTH ≤15.5 pg/mL, and postoperative serum cCa concentrations&lt;8.0 mg/dL significantly predicted symptomatic hypocalcemia (P = 0.009, P = 0.006, and P = 0.0001, respectively). The sensitivities of ΔPTH, PoPTH level, and postoperative serum cCa concentration to predict symptomatic hypocalcemia were 67%, 64%, and 100%, respectively.

Conclusion

Although PTH decline significantly correlates with symptomatic hypocalcemia, a considerable number of patients may experience hypocalcemic symptoms despite normal PoPTH levels. Analysis of serum Ca concentrations at 24 hours postoperatively help to achieve a more precise prediction of patients who bear a high risk for developing hypocalcemic symptoms.

Current predictive models do not accurately differentiate between single and multi gland disease in primary hyperparathyroidism: a retrospective cohort study of two endocrine surgery units

Background Minimally invasive parathyroidectomy (MIP) for primary hyperparathyroidism is dependent upon accurate prediction of single-gland disease on the basis of preoperative imaging and biochemistry. The aims of this study were to validate currently available predictive models of single-gland disease in two UK cohorts and to determine if these models can facilitate MIP. Methods This is a retrospectively cohort study of 624 patients who underwent parathyroidectomy for primary hyperparathyroidism in two centres between July 2008 and December 2013. Two recognised models: CaPTHUS (preoperative calcium, parathyroid hormone, ultrasound, sestamibi, concordance imaging) and Wisconsin Index (preoperative calcium, parathyroid hormone) were validated for their ability to predict single-gland disease. Results The rates of single- and multi-gland disease were 491 (79.6%) and 126 (20.2%), respectively. Cure rates in centres 1 and 2 were 93.2% and 93.8%, respectively (P = 0.789). The positive predictive value (PPV) of CaPTHUS score . 3 in predicting single-gland disease was 84.6%, compared with 100% in the original report. CaPTHUS . 4 and 5 had a PPV of 85.1 and 87.1, respectively. There were no differences in Wisconsin Index (WIN) between patients with single- and multi-gland (P = 0.573). A WIN greater than 1600 and weight of excised gland greater than 1 g had a positive predictive value of 86.7% for single-gland disease. Conclusions The use of CaPTHUS and WIN indices without intraoperative adjuncts (such as IOPTH) had the potential to result in failure to cure in up to 15% (CaPTHUS) and 13% (WIN) of patients treated by MIP targeting a single enlarged gland.

A Prospective Study on Role of Supplemental Oral Calcium and Vitamin D in Prevention of Postthyroidectomy Hypocalcemia

BACKGROUND

Postoperative transient hypocalcemia is sequelae of total thyroidectomy (TT), which is observed in up to 50% of patients. Routine oral calcium and Vitamin D supplementation have been proposed to prevent symptomatic hypocalcemia preventing morbidity and facilitating early discharge.

PATIENTS AND METHODS

A total of 208 patients with nontoxic benign thyroid disorders, undergoing TT, were serially randomized into four groups: Group A (no supplements were given), Group B (oral calcium - 2 g/day given), Group C (calcium and calcitriol - 1 mcg/day are given), and Group D (calcium, calcitriol, and cholecalciferol - 60,000 IU/day are given). Patients were monitored for clinical and biochemical hypocalcemia (serum calcium, [Sr. Ca] <8 mg/dl), along with serum intact parathormone (Sr. PTH) and magnesium 6 h after surgery and Sr. Ca every 24 h. Intravenous (IV) calcium infusion was started, if any of the above four groups exhibit frank hypocalcemia. Patients are followed up with Sr. Ca and Sr. PTH at 3 and 6 months.

RESULTS

All groups were age and sex matched. Hypocalcemia was observed in 72/208 (34.61%) cases. Incidence of hypocalcemia was higher in Group A (57.69%) and Group B (50%) compared to Group C (15.38%) and Group D (15.38%). Hypocalcemia necessitating IV calcium occurred in 31/208 (14.90%) patients. IV calcium requirement exceeded in Group A (26.92%) and Group B (23.07%) compared to Group C (5.76%) and Group D (3.84%). There was no statistical difference in basal levels of serum Vitamin D, calcium, magnesium, intact PTH, and 6 h after surgery. Permanent hypoparathyroidism developed in five patients on follow-up.

CONCLUSION

Routine postoperative supplementation of oral calcium and Vitamin D will help in the prevention of postthyroidectomy transient hypocalcemia significantly. Preoperative Vitamin D levels do not predict postoperative hypocalcemia.

Early prediction of hypocalcemia following thyroid surgery. A prospective randomized clinical trial

PURPOSE

The aim of this randomized-controlled trial was to validate the results of a previous prospective single-cohort observational study conducted in the same surgical unit regarding the use of concomitant intact parathyroid hormone (iPTH) and serum calcium measurement in predicting hypocalcemia after total thyroidectomy.

METHODS

From January 2014 to January 2015, 150 patients underwent total thyroidectomy in our department and were randomized into two groups. The experimental group was submitted to iPTH assay 6 h after surgery while the control group was submitted to a daily assay of serum calcium and phosphorus. Sensitivity and specificity of different serum measurements have been calculated using the receiver-operator characteristics (ROC) curve.

RESULTS

The prevalence of hypocalcemia was 14.25% in both groups. The assay of iPTH 6 h after surgery combined with the serum calcium assay 24 h after surgery yielded the highest diagnostic accuracy in predicting hypocalcemia using ROC curves, with 100% sensitivity and 100% specificity.

CONCLUSIONS

According to our previous study, the combined measurement of iPTH 6 h after surgery and of serum calcium 24 h after surgery are highly predictive of early postoperative hypocalcemia. These results are important in selecting the patients eligible for early discharge and those who need calcium and vitamin D supplementation.

Protocol for management after thyroidectomy: a retrospective study based on one-center experience

BACKGROUND AND AIM

The optimal approach to detect and treat symptomatic hypocalcemia (SxH) after thyroidectomy is still uncertain. In our retrospective study, we sought to set a standardized postoperative management protocol on the basis of relative change of parathyroid hormone (PTH) and absolute value of postoperative day 1 (POD1) PTH.

METHODS

Patients who underwent thyroidectomy were identified retrospectively in our prospective database. Blood was collected 1 day before surgery and on POD1. Extra calcium and calcitriol supplement was prescribed when necessary. Meanwhile, postoperative signs of SxH were treated and recorded in detail. Patients were followed up for 1 month after surgery and then 3 months thereafter.

RESULTS

A total of 744 patients were included in the final analysis. Transient SxH occurred in 86 (11.6%) patients, and persistent SxH occurred in 4 (0.54%) patients in more than half year after surgery. Relative decrease of PTH reached its maximal discriminative effect at 70% (area under the curve [AUC] =0.754), with a sensitivity of 72.1% and a specificity of 75%. In Group 1 (≤70%), 24 (4.67%) patients were interpreted as having SxH, whereas in Group 2, 62 (27.0%) patients had SxH (>70%), P<0.001. Days of symptom relief in Group 1-1 (1, 2) were significantly shorter than those in Group 2-2 (1, 10), P=0.023. In Group 2, 112 (80%) patients with POD1 PTH <1 pmol/L were treated with calcitriol, whereas only 8 (8.89%) patients with POD1 PTH ≥1 pmol/L were treated with calcitriol (P<0.001). According to relief of SxH and recovery of parathyroid function, treating with and without calcitriol showed no difference in patients with POD1 PTH <1 and ≥1 pmol/L.

CONCLUSION

Relative decrease of PTH >70% is a significant risk factor for SxH in post-thyroidectomy. The decreasing percent of PTH ≤70% ensures discharge on POD1, but longer hospitalization was advocated for patients with decreasing percent of PTH >70%, who needed extra calcitriol supplement when POD1 PTH <1 pmol/L.

Early discharge after total thyroidectomy: a retrospective feasibility study

AIM

The continued hospitalization after total thyroidectomy is often due to the onset of hypocalcemic complications more than 24 hours after surgery. So it would be important to predict which patients will not develop the hypocalcemic complication to discharge them early. This was the aim of our study.

PATIENTS AND METHODS

Our retrospective study was conducted on 327 consecutive thyroidectomized patients, operated on for benign and malignant diseases. We evaluated the values of preoperative serum calcium levels (Cal0) and of the first postoperative day (Cal1) and two new variables were calculated (dCal and dCaln). The same thing was made on a subgroup of 111 patients in whom also parathiroyd hormone (PTH) values were detected. Statistical analysis was performed with the goal of determining if we could establish a safe criterion for discharge at 24 hours after surgery and if there is a correlation between suitability for discharge and diagnosis.

RESULTS

As to discharge, the predictive power of the discriminant function applied was significant both on the total of patients and in the subgroup of 111 patients, but it was clinically unacceptable because it would expose us to a 21% to 27% error rate. It is not possible to identify a threshold, below which to consider patients surely dischargeable. The diagnosis does not appear correlated with the suitability for discharge.

CONCLUSION

On the basis of serum calcium and PTH levels in the first postoperative day, it is impossible to predict which patients can be discharged 24 hours after surgery without incurring in hypocalcemic complications.

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

BACKGROUND

Postoperative hypoparathyroidism is the most common complication after total thyroidectomy, owing to unintentional injury or decreased blood flow to the parathyroid glands. Prediction of postoperative hypoparathyroidism would be helpful for surgeons to manage postoperative hypocalcemia. In this study, we scored the discoloration of the parathyroid glands using a new parathyroid scoring system and evaluated the correlation between the parathyroid score and duration of required calcium supplementation after total thyroidectomy.

METHODS

A total of 316 patients undergoing total thyroidectomy between November 2009 and April 2010 were enrolled in this retrospective study. Parathyroid scoring was performed by one experienced surgeon. The status of each of the 4 parathyroid glands was classified as normal color (3 points), slightly discolored (2 points), dark discoloration (1 point), or loss of the gland (0 points), resulting in possible total scores of 0-12. Serum parathyroid hormone (PTH), serum calcium, and ionized calcium concentrations were measured at 2 hours, 2 weeks, 3 months, 6 months, and 1 year after surgery. Patients were also divided into three groups based on the duration of required calcium supplementation: no required supplementation (n = 260, 82.3%), required supplementation for <6 months (n = 38, 12%), and required supplementation for ≥6 months (n = 18, 5.75%).

RESULTS

Parathyroid scores were positively correlated with ionized PTH concentrations at 2 hours (r = 0.053, p < 0.001), 2 weeks (r = 0.056, p < 0.001), 3 months (r = 0.032, p<0.001), 6 months (r = 0.072, p < 0.001), and 1 year (r = 0.071, p < 0.001) after thyroidectomy. Parathyroid scores were significantly and inversely associated with the duration of required calcium supplementation (p = 0.001).

CONCLUSIONS

Parathyroid scores at the end of surgery might be helpful for predicting the degree of postoperative hypocalcemia after total thyroidetomy.

A rare case of malignant fibrous histiocytoma (pleomorphic undifferentiated sarcoma NOS) of the vocal fold

Malignant fibrous histiocytoma, also known as pleomorphic undifferentiated sarcoma not otherwise specified, arises in numerous organs. The first-line treatment is complete excision of the mass, but in some cases postoperative chemo- and/or radiotherapy is recommended. Only a few cases of malignant fibrous histiocytoma of the vocal fold have been previously reported in the literature. We report a new case, which originated in the true vocal fold of a 65-year-old man. The mass was removed via CO2 laser excision with preservation of the vocal fold and without the need for further treatment. At 3 years of follow-up, the patient remained recurrence-free.

Post-thyroidectomy hypocalcemia: Impact on length of stay

Hypocalcemia is a recognized complication following thyroid surgery. Variability in the definition of hypocalcemia and different opinions on its management can lead to unnecessary patient morbidity and longer hospital stays as a result of inappropriate or untimely treatment. Therefore, we developed a management guideline for the recognition and treatment of post-thyroidectomy hypocalcemia, and we conducted a retrospective study to assess its impact on length of stay (LOS). Between April 1, 2007, and March 31, 2009, 29 adults had undergone a total or completion thyroidectomy at our large district general hospital. Of this group, postoperative hypocalcemia (defined as a serum calcium level of <2.00 mmol/L) developed in 13 patients (44.8%) during the first 3 postoperative days. Our guideline went into effect on July 1, 2009, and from that date through June 30, 2010, 18 more adults had undergone a total or completion thyroidectomy. Of that group, hypocalcemia developed in 7 patients (38.9%); the guideline was actually followed in 5 of these 7 cases (71.4%). In the preguideline group, the development of hypocalcemia increased the mean LOS from 2.0 days to 7.0 days (p < 0.001). The management of postoperative hypocalcemia in these cases was highly variable and was dictated by variations in practice rather than patient needs. In the postguideline group, postoperative hypocalcemia increased the mean LOS from 2.7 days to only 3.7 days (p = 0.07). While the difference between LOS in the two hypocalcemic groups did not reach statistical significance, we believe it merely reflects the relatively small number of patients rather than any lack of guideline efficacy. The implementation of a simple flowchart guideline for the management of postoperative hypocalcemia in our hospital has resulted in more uniform management and a reduced LOS.

2016 American Thyroid Association Guidelines for Diagnosis and Management of Hyperthyroidism and Other Causes of Thyrotoxicosis

BACKGROUND

Thyrotoxicosis has multiple etiologies, manifestations, and potential therapies. Appropriate treatment requires an accurate diagnosis and is influenced by coexisting medical conditions and patient preference. This document describes evidence-based clinical guidelines for the management of thyrotoxicosis that would be useful to generalist and subspecialty physicians and others providing care for patients with this condition.

METHODS

The American Thyroid Association (ATA) previously cosponsored guidelines for the management of thyrotoxicosis that were published in 2011. Considerable new literature has been published since then, and the ATA felt updated evidence-based guidelines were needed. The association assembled a task force of expert clinicians who authored this report. They examined relevant literature using a systematic PubMed search supplemented with additional published materials. An evidence-based medicine approach that incorporated the knowledge and experience of the panel was used to update the 2011 text and recommendations. The strength of the recommendations and the quality of evidence supporting them were rated according to the approach recommended by the Grading of Recommendations, Assessment, Development, and Evaluation Group.

RESULTS

Clinical topics addressed include the initial evaluation and management of thyrotoxicosis; management of Graves' hyperthyroidism using radioactive iodine, antithyroid drugs, or surgery; management of toxic multinodular goiter or toxic adenoma using radioactive iodine or surgery; Graves' disease in children, adolescents, or pregnant patients; subclinical hyperthyroidism; hyperthyroidism in patients with Graves' orbitopathy; and management of other miscellaneous causes of thyrotoxicosis. New paradigms since publication of the 2011 guidelines are presented for the evaluation of the etiology of thyrotoxicosis, the management of Graves' hyperthyroidism with antithyroid drugs, the management of pregnant hyperthyroid patients, and the preparation of patients for thyroid surgery. The sections on less common causes of thyrotoxicosis have been expanded.

CONCLUSIONS

One hundred twenty-four evidence-based recommendations were developed to aid in the care of patients with thyrotoxicosis and to share what the task force believes is current, rational, and optimal medical practice.

One-hour PTH after thyroidectomy predicts symptomatic hypocalcemia

BACKGROUND

A major morbidity after total thyroidectomy is hypocalcemia. Although many clinical factors and laboratory studies have been correlated with both biochemical and symptomatic hypocalcemia, the ideal use and timing of these tests remain unclear. We hypothesize 1-h (PACU) parathyroid hormone (PTH) will identify patients at risk for symptomatic hypocalcemia.

METHODS

This prospective study evaluated 196 patients undergoing total thyroidectomy. Serum calcium and PTH levels were measured 1 h after surgery and on postoperative day 1 (POD1). Performance of a central compartment lymph node dissection, parathyroid autotransplantation, indication for procedure, pathology, and presence of parathyroid tissue in the pathology specimen were recorded.

RESULTS

Of 196 patients, nine (4.6%) developed symptomatic hypocalcemia. Thirty four (17.3%) had a 1-h PACU PTH ≤10 pg/dL, whereas 31 (15.8%) had a POD1 PTH of ≤10. Five (56%) of the nine symptomatic patients underwent central compartment lymph node dissection, four (44%) had parathyroid autotransplantation, and four (44%) had a PACU PTH ≤10. PACU and POD1 PTH levels were correlated (R(2) = 0.682). Multivariate regression identified central compartment dissection, autotransplantation, and PACU or POD1 PTH correlated with symptomatic hypocalcemia. PACU PTH, POD1 PTH, PACU Ca, malignant final pathology, and age ≤45 y correlated with biochemical hypocalcemia.

CONCLUSIONS

A 1-h postoperative PACU PTH is equivalent to POD1 PTH in predicting the development of symptomatic hypocalcemia. Biochemical hypocalcemia was not predictive of symptoms in the immediate postoperative period. Lymph node dissection and parathyroid autotransplantation correlated with symptomatic hypocalcemia and improve the sensitivity of biochemical screening alone.

The role of vitamin D in post-thyroidectomy hypocalcemia: Still an enigma

BACKGROUND

There is conflicting evidence regarding the role of vitamin D deficiency in the development of post-thyroidectomy hypocalcemia. Recent reports show postoperative parathormone (PTH) is unreliable in predicting post-thyroidectomy hypocalcemia in vitamin D deficient patients. We conducted this study to analyze the role of vitamin D status in the development of post-thyroidectomy hypocalcemia and to evaluate its effect on the predictability of PTH as a marker for post-thyroidectomy hypocalcemia.

METHOD

A retrospective review of prospectively collected data of patients undergoing thyroidectomy between August 2007 to September 2013 (n = 150) was performed. Results of preoperative calcium, albumin, vitamin D, PTH and postoperative calcium, albumin, and PTH were collated. Patients were divided into 2 groups based on their vitamin D status: group A, vitamin D ≥ 20 ng/mL and group B, vitamin D < 20 ng/mL.

RESULTS

Vitamin D deficiency was present in 80 (53.3%) patients and post-thyroidectomy hypocalcemia developed in 67 (44.7%). The incidence of postoperative hypocalcemia was similar in both the groups (48.6% and 41.3%, respectively). Vitamin D status was not associated with the development of post-thyroidectomy hypocalcemia (P = .23). Postoperative PTH of <8 pg/mL was strongly associated with the development of hypocalcemia in both the groups (P = .0002 and .0045, respectively). The area under the receiver operator characteristic curve in group B (0.68) was less than in group A (0.76; P = .41).

CONCLUSION

The majority of patients were vitamin D deficient in this cohort, but this did not increase the risk of post-thyroidectomy hypocalcemia, nor did it interfere with the predictability of PTH as a marker of post-thyroidectomy hypocalcemia.

Recovery from Permanent Hypoparathyroidism After Total Thyroidectomy

BACKGROUND

Permanent hypoparathyroidism after total thyroidectomy is a rare but potentially serious iatrogenic complication. The aim of this study was to investigate the rate of recovery from postoperative, permanent hypoparathyroidism in patients undergoing thyroidectomy without parathyroid autotransplantation.

METHODS

This study was a prospective case series with a postoperative follow-up of up to 3 years. We enrolled patients with thyroid cancer who underwent total thyroidectomy with central compartment dissection, with or without lateral neck dissection, and who had postoperative permanent hypoparathyroidism, defined as serum levels of intact parathyroid hormone (PTH) <15 pg/mL for at least 1 year. In the postoperative follow-up period, the serum levels of PTH and calcium were measured regularly. Recovery from permanent hypoparathyroidism was defined as return to normal serum levels of PTH (15-65 pg/mL) and calcium (8.5-10.1 mg/dL) without calcium and/or vitamin D supplementation.

RESULTS

In the 1467 patients who underwent total thyroidectomy, 22 presented with permanent postoperative hypoparathyroidism. In 5 of these 22 patients, the PTH levels increased steadily and returned to normal in 27.6±2.9 months, after which supplementation of calcium and vitamin D could be discontinued.

CONCLUSIONS

Although recovery from permanent hypoparathyroidism is rare, patients should be monitored for serum PTH levels so that unnecessary treatments such as calcium and vitamin D supplementation can be avoided.