Same-day discharge after total thyroidectomy: the value of 6-hour serum parathyroid hormone and calcium levels

BACKGROUND: The purpose of this study was to determine whether patients who undergo total thyroidectomy will have postoperative hypocalcemia develop when they reach the critical 6-hour serum levels defined as parathyroid hormone (PTH) > or =28 ng/L and simultaneous corrected calcium > or =2.14 mmol/L. METHODS: This was a prospective study involving 70 consecutive total thyroidectomy patients. There were 51 women and 19 men involved in the study. The mean age was 49.3 years (range, 21-76 years). Patients who had completion thyroidectomy or neck dissections were excluded. Patients undergoing parathyroidectomy at the time of thyroidectomy were also excluded. PTH and corrected calcium levels were measured postoperatively at 6, 12, and 20 hours. RESULTS: Hypocalcemia developed in 24% (17 of 70) of the patients. Of the 53 patients who remained normocalcemic, 68% (36 of 53) reached the 6-hour critical level. None of the hypocalcemic patients (0 of 17) attained the 6-hour critical level (chi-square test p < .0001). This translates into a specificity of 100% (95% confidence interval [CI], 80.5% to 100%) and a positive predictive value of 100% (95% CI, 90.1% to 100%). CONCLUSIONS: The simultaneous evaluation of PTH and corrected calcium levels 6 hours after thyroidectomy allows for an accurate prediction of the trend of serum calcium. This study enables us to confidently consider same-day discharge for most of our thyroidectomy patients.     

Recovery of parathyroid function after total thyroidectomy: long-term follow-up study

BACKGROUND: To prevent postoperative hypoparathyroidism following total thyroidectomy, the parathyroid glands are preserved in situ and/or resected or devascularized parathyroid glands are autotransplanted. A retrospective investigation was conducted utilizing biochemical and specific endocrine assessments to evaluate the difference in recovery of parathyroid function in the long term. METHODS: A total of 103 patients underwent total thyroidectomy at Second Department of Surgery, School of Medicine, Kagawa University between 1990 and 1998. These patients were divided into a preservation group (n = 17), with only preserved glands in situ; a combination group (n = 72), consisting of patients with one or more parathyroid glands preserved in situ and one or more autotransplanted parathyroid glands; and an autotransplantation group (n = 14), with only transplanted glands. RESULTS: The overall incidence of permanent hypoparathyroidism in the preservation group, the combination group, and the autotransplantation group was 0%, 1.4%, and 21.4%, respectively. The mean levels of intact parathyroid hormone in the preservation group, the combination group, and the autotransplantation group recovered to 102%, 107%, and 50% of the preoperative levels at 5-year follow up. CONCLUSION: The results of the present study suggest that parathyroid glands should be preserved in situ whenever possible, to promote better recovery of postoperative function, and that only autotransplantation produces inadequate recovery of long-term function.     

Intraoperative parathyroid hormone assay for management of patients undergoing total thyroidectomy

BACKGROUND: Rapid parathyroid hormone (PTH) assay has been applied to predict hypocalcemia after thyroidectomy compared with conventional close monitoring of serum calcium levels. We evaluated the reliability of intraoperative intact PTH (ioPTH) assay to predict hypocalcemia after total thyroidectomy and sought to develop an algorithm for the management of postthyroidectomy patients. METHODS: Rapid PTH assays were performed before and after thyroidectomy for 92 new patients receiving total thyroidectomy. Preoperative and postoperative serum calcium and standard PTH levels were serially obtained to 6 months after surgery RESULTS: Postoperative hypocalcemia developed in 34 of 92 patients (37%), who showed significantly lower ioPTH values compared with those of normocalcemic patients (mean 9.2 pg/mL vs 31.3 pg/mL). The ioPTH levels were significantly correlated with standard PTH levels (p < .001, r > 0.62), but not with early serum calcium levels within 8 hours after the operation. Sensitivity and specificity of ioPTH levels of <15.0 pg/mL for the prediction of postoperative hypocalcemia were 85% and 84%, respectively. A value of >15.0 pg/mL and <70% decline in ioPTH after thyroidectomy can reliably identify normocalcemic patients during thyroidectomy or patients requiring close monitoring and early calcium supplement CONCLUSIONS: Rapid ioPTH assay can reliably monitor parathyroid function after thyroidectomy and predict postoperative hypocalcemia. The proposed algorithm based on rapid PTH levels will lead to improved prediction of normocalcemic patients.     

Serum intact parathyroid hormone as a predictor of hypocalcaemia after total thyroidectomy

BACKGROUND: Hypocalcaemia from hypoparathyroidism is a complication of total thyroidectomy. The aim of the present study was to determine whether an early postoperative level of serum parathyroid hormone (PTH) after total thyroidectomy predicts the development of significant hypocalcaemia and the need for treatment. METHODS: Patients undergoing total thyroidectomy had their serum level of intact PTH checked 1 h after removal of the thyroid gland. Serum calcium level was checked on the following morning. Oral calcium and/or calcitriol was commenced if the patient developed hypocalcaemic symptoms, or if the corrected serum calcium level was <2.0 mmol/L. RESULTS: Seventy-nine patients were included in the present study. Thirteen patients had symptoms of hypocalcaemia on postoperative days 1 or 2 and 66 patients remained asymptomatic. The postoperative intact PTH, day 1 calcium and day 2 calcium was 0.32 +/- 0.60 pmol/L, 2.01 +/- 0.11 mmol/L, and 2.02 +/- 0.16 mmol/L, respectively, for the symptomatic group and 1.98 +/- 1.25, 2.21 +/- 0.13, and 2.19 +/- 0.14, respectively, for the asymptomatic group. Calcium support was given to 25 patients, of whom 14 also required calcitriol. CONCLUSION: Serum PTH 1-h after total thyroidectomy is a reliable predictor of hypocalcaemia and can allow safe early discharge of patients from hospital.     

Intact parathyroid hormone measurement at 24 hours after thyroid surgery as predictor of parathyroid function at long term

Background

There is no consensus about the usefulness of postoperative intact parathyroid hormone (iPTH) determination to predict permanent hypoparathyroidism (pHPP). We evaluated the value of calcium (Ca²⁺) and iPTH concentration at 24 hours after total thyroidectomy (TT) for predicting pHPP.

Methods

Ca²⁺ and iPTH levels from 70 consecutive patients who underwent TT were measured at 24 hours and 6 months after TT.

Results

Five patients (7.1%) developed pHPP. An iPTH concentration ≤5.8 pg/mL at 24 hours after TT identified patients at risk for pHPP (sensitivity, 100%; specificity, 81.5%), but it was not accurate enough to predict its development (positive predictive value, 30%). Conversely, an iPTH level >5.8 pg/mL predicted normal parathyroid function at 6 months (negative predictive value, 100%). Compared with iPTH, a postoperative Ca²⁺ level ≤1.95 mmol/L was 60% sensitive and 78.5% specific to predict pHPP.

Conclusions

An iPTH concentration >5.8 pg/mL on the first postoperative day rules out pHPP with much better diagnostic accuracy than Ca²⁺. Postoperative iPTH could be helpful in identifying patients at risk for developing pHPP.     

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.     

原位保留甲状旁腺血供及甲状旁腺自体移植术

目的 介绍甲状腺肿瘤手术中保护甲状旁腺血供及甲状旁腺自体移植的方法及疗效.方法 46例全甲状腺切除或近全切除手术中,血管化甲状旁腺保留24例,单纯自体甲状旁腺移植5例,1～2枚甲状旁腺血管化保留同时其余甲状旁腺Ⅰ期自体移植17例.结果 应用此法行全甲状腺切除或近全切除患者中,有2例原位血管化保留甲状旁腺及3例血管化保留+自体甲状旁腺移植患者术后48～72 h内出现一过性低血钙,予以补钙后3 d左右恢复正常.2例单纯甲状旁腺自体移植患者术后出现低血钙,服用钙尔奇D/罗盖全4周～8周后复查血钙维持在正常水平.术后出现永久性甲状旁腺功能低下的仅1例(2.2%).结论 血管化甲状旁腺保留及自体甲状旁腺移植可大大降低全甲状腺切除或近全切除手术导致甲状旁腺功能低下的发生率.     

Parathyroid autotransplantation during thyroidectomy

Permanent hypoparathyroidism is a debilitating morbidity following thyroidectomy, with a reported incidence of up to 43%. Apart from meticulous dissection to preserve parathyroid glands and their blood supply, parathyroid autotransplantation (PA) has been increasingly employed to preserve parathyroid function. The adoption of PA during thyroidectomy has been reported to be associated with a low incidence of permanent hypoparathyroidism. Biochemical function of parathyroid autografts can be demonstrated objectively by forearm reimplantation or during long-term follow up. The clearest indication for PA is for inadvertently removed or devascularized parathyroid glands during thyroid surgery. Other strategies, including routine autotransplantation of at least one parathyroid gland, can be considered, but is associated with a high incidence of transient hypocalcaemia. Apart from refinement in technique to facilitate graft success, a reliable way to assess overall parathyroid function or viability of individual parathyroid gland may assist in monitoring parathyroid function and selecting patients requiring this procedure to prevent permanent hypoparathyroidism.     

Selective parathyroid auto‐transplantation during thyroidectomy

Aim: Permanent hypoparathyroidism is a debilitating morbidity following thyroidectomy and parathyroid auto‐transplantation has been shown to be effective in preventing permanent hypoparathyroidism. Controversy exists regarding the benefit of routine versus selective auto‐transplantation. We evaluate the outcome of selective parathyroid auto‐transplantation in our hospital. Methods: A retrospective study was conducted to assess the incidence of postoperative hypocalcaemia. Indication for parathyroid auto‐transplant was doubtful viability of parathyroid gland during thyroidectomy. From 1 July 2000 to 30 June 2005, all patients who underwent total, subtotal and completion thyroidectomy were included. Other outcome measures including recurrent laryngeal nerve injury and operative time were also analyzed. Results: A total of 170 bilateral or completion thyroidectomies were performed within this period. Total, subtotal, and completion total thyroidectomies were performed in 103 (60.6%), 62 (36.5%), and five (2.9%) patients, respectively. Median age was 45 years (range 19–82). One hundred and twenty‐four patients (73%) had benign thyroid disease, and 46 patients (27%) had thyroid carcinoma. Parathyroid auto‐transplant was performed in 35 patients (20.6%). Mean operation time was 204 min (range 95–510 min). There was no difference in the operation time between the patients with parathyroid auto‐transplant and those without auto‐transplant (217 vs 200 min, P = 0.229). Transient hypocalcaemia occurred in 31 patients (18.2%) whereas two patients had permanent hypocalcaemia (1.2%). Permanent recurrent laryngeal nerve injury occurred in one patient (0.6%). Conclusions: The adoption of selective parathyroid auto‐transplant during thyroidectomy achieves an extremely low incidence of permanent hypoparathyroidism without excessive transient hypoparathyroidism.     

Parathyroid hormone assay predicts hypocalcaemia after total thyroidectomy

BACKGROUND: Postoperative parathyroid gland function after total thyroidectomy (TT) has traditionally been monitored by the measurement of serum calcium concentrations. The purpose of this study is to determine whether measurement of parathyroid hormone (PTH) concentrations in the early postoperative period accurately predicts patients at risk of developing hypocalcaemia. METHODS: A prospective cohort study of patients undergoing TT was carried out. PTH concentrations were measured preoperatively and at 4 and 23 h postoperatively. Serum calcium concentration was measured preoperatively and twice daily for 48 h after surgery. RESULTS: One hundred patients undergoing TT were recruited into the study in the period June 2004 to July 2005. Benign multinodular goitre was the most common indication for surgery (77%). The incidence of temporary hypocalcaemia (Ca < 2.0 mmol/L) was 18%. The mean PTH concentration at 4 h after surgery was 22.3 ng/L and was not significantly different from the 23-h concentration of 23.2 ng/L (P = 0.18). A PTH concentration of < or = 3 ng/L measured at 4 h after surgery had a sensitivity, specificity and likelihood ratio of 0.71, 0.94 and 11.3, respectively, for predicting postoperative hypocalcaemia. The accuracy of a single PTH concentration at 4 h was good for predicting hypocalcaemia (area under receiver-operator characteristic curve 0.90; confidence interval 0.81-0.96). There was no significant difference in accuracy between the 4- and 24-h PTH concentrations (P = 0.14). CONCLUSIONS: A single measurement of PTH concentration in the early postoperative period after TT reliably predicts patients who are likely to develop hypocalcaemia. This approach facilitates early discharge and may decrease the need for multiple postoperative blood tests.     

Percutaneous autotransplantation of parathyroid tissue into the forearm muscles

We developed a simple and easy nonsurgical percutaneous method for autografting parathyroid tissue into the forearm muscles. This method was applied to 30 patients suffering from secondary hyperparathyroidism who were then refractory to medical treatment. The operative results were then compared with 16 patients who underwent treatment using Wells' method. The graft “take”, judged by a significant intact parathyroid hormone (PTH) ratio (>1.5) between grafted and nongrafted arm vein blood, was 82% for the percutaneous method group and 75% for the Wells' method group, respectively. The percentage of recurrent hyperparathyroidism necessitating a subtotal removal of the autograft was equal in the two groups. No complications were noted for either method. Wells' method can thus be replaced by this simple and easy nonoperative method.     

Australian Endocrine Surgeons Guidelines AES06/01. Postoperative parathyroid hormone measurement and early discharge after total thyroidectomy: analysis of Australian data and management recommendations

Background: The risk of hypocalcaemia after thyroidectomy has traditionally mandated inpatient monitoring for signs and symptoms as well as frequent measurement of serum calcium levels. In recent years there has been much interest in the published work about the use of intact parathyroid hormone (PTH) to better predict hypocalcaemia after thyroidectomy. Although generally accurate, the use of intact parathyroid hormone in Australia has not become widespread. On behalf of the Australian Endocrine Surgeons an analysis of Australian data on the use of PTH levels to predict hypocalcaemia after thyroidectomy was carried out. The data were analysed with a view to making recommendations about the use of this test in clinical practice and the feasibility of achieving safe early discharge for patients. Methods: Four recently published or presented Australian studies on the use of early postoperative PTH levels after total or completion thyroidectomy to predict post‐thyroidectomy hypocalcaemia were analysed. Patients were stratified into either normal or low PTH groups as defined by the normal ranges set by each laboratory and rates of hypocalcaemia were analysed. Results: A total of 458 patients were examined. Seventy‐six per cent of the patients had PTH in the normal range and hypocalcaemia (serum‐corrected calcium cCa²⁺ < 2.00 mmol/L) occurred in 17.9% of patients. Sensitivity, specificity and positive predictive values of a normal postoperative PTH level as a predictor of normocalcaemia are 92.6, 70.7 and 92.3%, respectively. Low PTH as a predictor of hypocalcaemia is poor. The overall sensitivity, specificity and positive predictive values are 70.7, 92.6 and 71.6%, respectively. Conclusion: Normal postoperative PTH levels accurately predict normocalcaemia after total or completion thyroidectomy. PTH levels should ideally be drawn 4 h postoperatively and patients with PTH in the normal range can be safely discharged on the first postoperative day. Use of oral calcium supplements, either as needed or routinely, will avoid mild symptoms that may develop in 7% without treatment.     

ROUTINE AUTOTRANSPLANTATION OF AT LEAST ONE PARATHYROID GLAND DURING TOTAL THYROIDECTOMY MAY REDUCE PERMANENT HYPOPARATHYROIDISM TO ZERO

Background : Permanent hypoparathyroidism, although a recognized complication of total thyroidectomy, is an outcome that all endocrine surgeons try to avoid. Methods : To minimize the risk of postoperative hypoparathyroidism a strategy was developed of routine autotransplantation of at least one parathyroid gland into the ipsilateral sternomastoid muscle during every total thyroidectomy. One hundred consecutive patients undergoing total thyroidectomy were included in the study. Serum calcium and albumin levels were measured pre-operatively, on the first 2 postoperative days, and after 2 weeks, or until return to normal serum calcium levels without calcium supplementation. If patients developed biochemical evidence or symptoms of hypocalcaemia postoperatively, a calcium replacement was administered according to defined protocol. Results : In 74 cases one parathyroid gland was autotransplanted: 44 for inadvertent removal or anatomical reasons, 19 because of devascularization (assessed by a cut through the gland’s capsule and evaluation of the capillary bleeding pattern), and 11 by protocol. In 25 cases, two or more glands were autotransplanted. Fourteen patients developed symptoms of hypocalcaemia and received calcium supplementation, as did another 13 asymptomatic patients with only biochemical evidence of hypocalcaemia. At follow-up 3 months postoperatively the incidence of permanent hypoparathyroidism was zero, with all patients being normocalcaemic without calcium supplementation. Conclusions : This strategy, easily adopted by any experienced surgeon, has the potential to eliminate permanent hypoparathyroidism following total thyroidectomy.