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.     

Assessment of parathyroid autotransplantation for preservation of parathyroid function after total thyroidectomy

BACKGROUND: Hypoparathyroidism with permanent hypocalcemia is a well-recognized complication after thyroid surgery. AIM: This study was conducted to assess the role of immediate parathyroid autotransplantation in the preservation of parathyroid function after total thyroidectomy. PATIENTS AND METHODS: Twenty-eight patients had autotransplantation of parathyroid glands resected or devascularized during total thyroidectomy. Data were collected prospectively regarding demographics, indication for surgery, operative procedure, pathologic diagnosis, number of glands transplanted, and subsequent course. Thyroid nodules were evaluated by ultrasonography, radionuclide scanning, and/or fine-needle aspiration cytology. All patients had serum ionized calcium, phosphorus, and intact parathyroid hormone (PTH) levels measured preoperatively and monitored regularly postoperatively for a period of 14 weeks and again at 6 months after operation. Patients were categorized into three groups according to the number of glands transplanted: one (group 1, n = 6), two (group 2, n = 14), or three glands (group 3, n = 8). In three other volunteers, one parathyroid gland was transplanted in the brachioradialis and subjected to electron microscopy 1, 2, and 4 weeks after transplantation. RESULTS: Total thyroidectomy was performed for malignant disease in 16 patients (57.1%) and for benign disease in 12 (42.9%) patients. All patients reverted to asymptomatic normocalcemia without the need for any medications within 4 to 14 weeks. Normal levels of serum markers were regained slower when one gland was transplanted compared with two or three glands (P <.01). Electron microscopic examination showed evidence of ischemic degeneration in the transplanted tissues 1 week postoperatively. Regeneration started by the second week and coincided with normalization of PTH levels. Optimum resting and nearly normal status of parathyroid tissue was achieved by the fourth week. CONCLUSIONS: This study showed that active PTH production coincides with regeneration of parathyroid cells and that autotransplantation of at least two resected or devascularized glands during total thyroidectomy nearly eliminates permanent postoperative hypoparathyroidism, thus improving the safety of total thyroidectomy performed for malignant or benign disease.     

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.     

Parathyroid autotransplantation during thyroidectomy. Results of long-term follow-up.

SUMMARY BACKGROUND DATA: Permanent hypoparathyroidism is a recognized complication of thyroidectomy. Operative strategies to prevent this complication include preservation of parathyroid glands in situ and autotransplantation of parathyroid glands resected or devascularized during thyroidectomy. METHODS: An analysis of 194 patients having thyroidectomy and simultaneous parathyroid autotransplantation at Barnes Hospital from 1990 to 1994 was performed. Data were collected regarding patient demographics, indication for thyroidectomy, operative procedure, pathologic diagnoses, and postoperative course, including biochemical assessment of parathyroid autograft function. RESULTS: Of 194 patients having either total, subtotal, or completion thyroidectomy, 104 (54%) experienced a [Ca(+2)]nadir less than or equal to 8.0 mg/dL and had symptoms and signs of hypocalcemia. Parathyroid autotransplantation was successful in 103 (99%) of these 104 cases and resulted in a 1.0% incidence of hypoparathyroidism in this series. CONCLUSIONS: Although preservation of parathyroid glands in situ is desirable, routine parathyroid autotransplantation during thyroidectomy virtually eliminates postoperative hypoparathyroidism. Normal parathyroid glands resected or devascularized during thyroidectomy for well-differentiated thyroid carcinoma or benign disease should be transplanted in the sternocleidomastoid muscle. Patients with Multiple Endocrine Neoplasia type 2A should have parathyroid glands resected at the time of thyroidectomy for medullary thyroid carcinoma and transplanted in the nondominant forearm. Postoperative management in most patients after thyroidectomy and parathyroid autotransplantation involves temporary calcium and vitamin D replacement and close biochemical evaluation. This precautionary measure of parathyroid autotransplantation markedly reduces the incidence of permanent postoperative hypoparathyroidism.     

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.     

Autotransplantation of at least one parathyroid gland during thyroidectomy in benign thyroid disease minimizes the risk of permanent hypoparathyroidism

OBJECTIVE:Permanent hypoparathyroidism is a distressing complication of thyroid surgery. The reported incidence varies between 0.4 and 13.8 % and is directly correlated to the extent of thyroidectomy. The aim of this retrospective study was to analyze whether simultaneous autotransplantation of at least one parathyroid gland during total thyroidectomy for benign thyroid disease could reduce the risk of permanent hypoparathyroidism. METHODS: Since 01/1999 all thyroid operations are prospectively recorded. Beside daily postoperative measurement of serum calcium level, iPTH is routinely determined on the third post op day. Patients with complications are followed closely. Postoperative hypoparathyroidism persisting for more than 6 months is defined permanent. RESULTS: Between 01/1999 and 02/2001 146 total thyroidectomies for benign thyroid disease have been performed (81 pat. with Graves disease, 62 with nodular goiter, 3 with thyroiditis de Quervain/Hashimoto). In 37 pat. (25 %) at least one parathyroid gland was simultaneously autotransplanted into the ipsilateral sternocleidomastoid muscle. Group I (no parathyroid autotransplantation, n = 109) and group II (parathyroid autotransplantation, n = 37) were comparable concerning patient age, thyroid disease and lowest post op calcium level (2.07 versus 2.05 mmol/l). The incidence of postoperative symptomatic hypocalcemia (14.7 % versus 21.6 %) and temporary hypoparathyroidism (15.6 % versus 18.9 %) was higher in group II patients (n. s.). Conversely, permanent hypoparathyroidism occurred exclusively in group I patients (2.75 %), patients with parathyroid autotransplantation (group II) did not develop this complication. CONCLUSIONS: Simultaneous autotransplantation of at least one parathyroid gland during total thyroidectomy for benign thyroid disease seems to minimize the risk of permanent hypoparathyroidism. The potential of routine autotransplantation in this setting has to be evaluated. The incidence of postoperative temporary hypocalcemia may be elevated with this policy.     

Does the number of autotransplanted parathyroid glands affect postoperative hypoparathyroidism and serum parathyroid hormone levels?

BackgroundTo investigate how number of autotransplanted parathyroid glands (PGs) affects the incidence of postoperative hypoparathyroidism and the recovery of parathyroid function.MethodsA systematic search was performed in the MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases. The evaluated indices included the incidence of postoperative transient and permanent hypoparathyroidism and parathyroid hormone (PTH) levels during follow-up.ResultsTwenty articles with 7291 patients were included. A higher incidence of transient hypoparathyroidism was found in the PG autotransplantation group than in the preservation group (odds ratio [OR]: 2.37; 95% confidence interval [CI]: 1.90, 2.96). However, there was no significant difference between the two groups regarding permanent hypoparathyroidism (OR: 1.17; 95% CI: 0.71, 1.91). Parathyroid hormone (PTH) levels in the PG autotransplantation group changed significantly more than the preservation group at postoperative 1-day and 1-month, but became similar at the 6-month, 1-year and 2-year follow-up. Autotransplantation of 2 and 3 PGs demonstrated a higher incidence of transient hypoparathyroidism than 1 PG (OR: 2.09; 95% CI: 1.41, 3.11 and OR: 9.70; 95% CI: 2.11, 44.39, respectively), but no significant difference was observed between the autotransplantation of 3 and 2 PGs (OR: 0.99; 95% CI: 0.03, 29.06). Additionally, the incidence of permanent hypoparathyroidism was not significantly different when different number of PGs was autotransplanted.ConclusionsPG autotransplantation is an effective mid- and long-term strategy for the preservation of parathyroid function. Although transient hypoparathyroidism was positively correlated with the number of autotransplanted PGs, no remarkable correlation was observed for permanent hypoparathyroidism.     

Routine parathyroid autotransplantation during thyroidectomy

BACKGROUND: Parathyroid autotransplantation (PTHAT) during thyroidectomy has been shown to reduce the incidence of permanent hypoparathyroidism. Although selective PTHAT is most commonly adopted, the value of routine PTHAT has not been well documented. METHODS: From January, 1998 to March, 1999, an operative strategy incorporating routine autotransplantation of at least 1 parathyroid gland was used during thyroidectomy. The postoperative outcome of patients (n = 118) was evaluated and compared with patients (n = 271) operated during a policy of selective PTHAT (January, 1995 to October, 1997). RESULTS: Two or more parathyroid glands were autotransplanted in 26 patients (22%) while 92 patients (78%) received autotransplantation of 1 parathyroid gland. Postoperative hypocalcemia occurred in 29 patients (25%) and 2 patients (1.7%) had permanent hypocalcemia develop. When a policy of selective PTHAT was adopted, 98 patients (36%) underwent PTHAT, and 5 patients developed permanent hypocalcemia (1.8%). The incidence of postoperative hypocalcemia was higher in patients who underwent routine PTHAT (25%) compared with that in patients who underwent selective PTHAT (15%) (P =.014). In addition, the operating time was significantly longer when routine PTHAT was adopted (153 minutes vs 130 minutes; P <.001). CONCLUSIONS: A low incidence of permanent hypoparathyroidism can be achieved by either routine or selective PTHAT during thyroidectomy but routine PTHAT is associated with a high incidence of postoperative hypocalcemia.     

Does autoimmune thyroid disease affect parathyroid autotransplantation and survival?

Background: While the increased risk to parathyroid gland preservation has long been recognized during surgery for thyroid cancer, the effect of different benign pathological conditions on parathyroid preservation has not previously been reported. The aim of this study was to examine parathyroid viability in relation to autoimmune thyroid disease. Methods: This is a retrospective cohort study including all patients having an initial total thyroidectomy (TT) performed by this unit during the period 2004–2005. Results: A total of 628 patients underwent TT in the study period. For the Graves' disease cases, 45 (62.5%) required the autotransplantation of one or less parathyroid gland, whereas 27 (37.5%) required two or more glands to be autotransplanted. This was significantly higher than for the benign thyroid disease group in which the respective figures were 242 (77.6%) and 70 (22.4%) (P= 0.01). Of the lymphocytic thyroiditis cases, 61 (65.5%) required the autotransplantation of one or less gland, whereas 32 (34.4%) required the autotransplantation of two or more glands. This was also significantly higher (P= 0.03). Temporary hypocalcaemia was significantly higher when two or more glands were autotransplanted (23 out of 177, 13.2%) than one or less gland autotransplanted (18 out of 451, 4.0%, P < 0.01). However, the overall incidence of permanent hypoparathyroidism was 1.0%, and there was no significant difference between the groups. Conclusion: TT performed for Graves' disease and lymphocytic thyroiditis results in the autotransplantation of more parathyroid glands, leading to a higher incidence of temporary hypocalcaemia post‐operatively. Despite this, the incidence of permanent hypoparathyroidism remains low at 1%.     

Dysfunction of calcium metabolism following resection of the thyroid gland. An analysis of important risk factors

PURPOSE: Dysfunction of the parathyroid glands is a typical complication following thyroid surgery. Risk factors for the development of postoperative symptomatic hypocalcemia were retrospectively analyzed. METHODS: 308 consecutive thyroid resections (women n = 236, men n = 72, mean age 53 years) performed in 1996 and 1997 were evaluated. Main diagnosis was non-toxic nodular goiter (n = 234, 76 %), 28 patients (9 %) had thyroid carcinoma. The most common operation performed was bilateral functional thyroid resection (n = 116, 38 %), the proportion of thyroidectomies was 14 % (n = 44). The patients with postoperative symptomatic hypocalcemia were followed for a median of 32 months. RESULTS: Clinical symptoms of hypocalcemia were observed in 18 patients (6 %) postoperatively. Three patients developed transient (n = 1) or permanent hypothyroidism (n = 2). In univariate analysis, the underlying thyroid disease, the method of operative therapy, removal, identification and autotransplantation of parathyroid glands, in multivariate analysis, thyroidectomy (relative risk 6.9) and removal of parathyroid glands (relative risk 23.9) were proved to be significant risk factors for the development of postoperative symptomatic hypocalcemia (p < 0.05). CONCLUSIONS: Patients with thyroidectomy, operation for thyroid carcinoma and intraoperative removal of parathyroid glands should be closely followed for postoperative hypocalcemia. Exact surgical technique provided, permanent hypoparathyroidism is rare, particularly if several parathyroid glands were identified intraoperatively and autotransplanted, if necessary.     

Latent hypoparathyroidism in patients with autotransplanted parathyroid glands

Eighteen patients had undergone radical surgery for thyroid carcinoma. In all of them four parathyroid glands had been verified by frozen-section biopsy and removed. Thereafter two, three or four glands were autotransplanted into muscle tissue. At least 1 year after the operation the patients underwent a calcium deprivation test. Before the test they all had normal serum calcium values without treatment. During the test seven patients remained normocalcemic, seven became hypocalcemic, and four had occasional low serum calcium values. After the test all were normocalcemic again. Patients with only autotransplanted parathyroid glands left after surgery should be tested for latent hypoparathyroidism.     

Applicability of intraoperative parathyroid hormone assay during thyroidectomy

OBJECTIVE: To evaluate the applicability of intraoperative parathyroid hormone (quick PTH) assay to monitor parathyroid function and to identify clinically significant hypocalcemia compared with postoperative serum calcium monitoring. SUMMARY BACKGROUND DATA: Close monitoring of serum calcium levels is a standard of care to identify post-thyroidectomy hypocalcemia due to parathyroid insufficiency. METHODS: Quick PTH assay was performed before and after thyroidectomy for 100 patients at risk of postoperative hypocalcemia and 20 control patients who underwent unilateral lobectomy. Postoperative serum calcium levels were closely monitored. RESULTS: Control patients had a normal but 38.9 +/- 5.9% (mean +/- SEM) decline in quick PTH after thyroidectomy. Eleven of 100 at-risk patients (11%) developed postoperative hypocalcemia. Hypocalcemic patients had significantly lower quick PTH values after thyroidectomy compared with that of normocalcemic patients. Serum calcium was significantly lower in hypocalcemic patients the morning after operation but not early after the operation (within 6 hours). A normal or less than 75% decline in quick PTH after thyroidectomy can accurately identify normocalcemic patients during surgery as compared to more than 24 hours by serum calcium monitoring. CONCLUSIONS: The quick PTH assay can monitor parathyroid function during thyroidectomy and identify patients at risk of clinically significant hypocalcemia much earlier than serum calcium monitoring. It may facilitate early discharge and the use of parathyroid autotransplantation during thyroidectomy.     

达芬奇机器人甲状腺手术中甲状旁腺的损伤因素及保护

目的分析达芬奇机器人甲状腺手术中甲状旁腺损伤的相关因素,探讨甲状旁腺保护的方法,避免永久性甲状旁腺功能减退的发生。 方法回顾性分析2014年1月至2016年5月在济南军区总医院甲状腺乳腺外科行达芬奇机器人甲状腺手术的190例患者的临床资料,统计术后患者出现低甲状旁腺激素(PTH)及低血钙的发生率,分析术后发生甲状旁腺功能减退的相关因素,探讨术中如何保护甲状旁腺及其功能。 结果患者术后暂时性低PTH的发生率为20.53%(39/190),暂时性低血钙的发生率为23.68%(45/190),术后随访无永久性甲状旁腺功能减退发生。甲状腺全切术后低PTH、低血钙的发生率高于腺叶 ＋ 峡部切除术者(χ²＝14.789,11.604;P＝0.000,0.001)。行中央区淋巴结清扫的患者术后低PTH、低血钙的发生率高于未清扫者(χ²＝11.200,17.771;P＝0.001,0.000)。甲状旁腺原位保留者术后低PTH、低血钙的发生率低于切除后自体移植者(χ²＝5.536,4.851,6.140,5.453;P＝0.019,0.028,0.013,0.020)。 结论在达芬奇机器人甲状腺手术中,甲状腺全切除、中央区淋巴结清扫、甲状旁腺切除后自体移植是造成患者术后暂时性甲状旁腺功能减退的重要影响因素。在达芬奇机器人手术系统下,准确识别甲状旁腺,精细化手术操作,原位保护甲状旁腺及血供,是预防永久性甲状旁腺功能减退的有效方法。     

Parathyroid autotransplantation during thyroidectomy: is frozen section necessary?

OBJECTIVE: To evaluate the accuracy of parathyroid gland identification and the need for routine frozen section examination before parathyroid autotransplantation during thyroidectomy. DESIGN: A prospective case series. SETTING: An endocrine surgical unit. PATIENTS: From January 1, 1995, to December 31, 1997, parathyroid autotransplantation was attempted for devascularized or inadvertently removed glands in 152 (33.7%) of 450 patients during thyroidectomy. Before autotransplantation, a biopsy specimen of the transplanted tissue was sent for histological examination without frozen section confirmation. MAIN OUTCOME MEASURES: Positive identification of parathyroid tissue in microscopic examination. RESULTS: Of 179 attempted autotransplantations of parathyroid glands, parathyroid tissue was confirmed in 167 biopsy specimens (93.3%). Incorrect identification of parathyroid gland occurred in 12 instances. The tissue mistaken as parathyroid gland included fat in 6 cases, thyroid tissue in 4 cases, lymph node in 1 case, and thymus in 1 case. Transplantation of at least 1 parathyroid gland (range, 1-3) was confirmed in 144 patients. For patients with confirmed parathyroid autotransplantation at risk of hypoparathyroidism (n = 112), postoperative transient hypocalcemia occurred in 22 (19.6%), while no patient developed any permanent hypocalcemia during a median follow-up of 6 months. CONCLUSIONS: Devascularized or inadvertently removed parathyroid glands can be identified expeditiously without routine frozen section during thyroid surgery. Immediate autotransplantation should be performed and permanent hypoparathyroidism can be avoided with this measure.     

Parathyroid Autotransplantation during Total Thyroidectomy—Does the Number of Glands Transplanted Affect Outcome?

Parathyroid autotransplantation is a technique for ensuring the continued function of parathyroid tissue at the time of total thyroidectomy (TT). The aim of this study was to ascertain whether the number of parathyroids transplanted affects the incidence of temporary and permanent hypoparathyroidism. A retrospective cohort study included all patients undergoing a TT in a single unit between July 1998 and June 2003. The number of parathyroids transplanted, the final pathology, and the incidence of temporary and permanent hypoparathyroidism were documented. Fisher’s exact test was used for statistical analysis. A total of 1196 patients underwent a TT during the 5 years studied. Of these, 306 (25.6%) had no parathyroids transplanted, 650 (54.3%), 206 (17.2%), 34 (2.8%) had 1,2, or 3 glands autotransplanted, respectively. The incidence of temporary hypoparathyroidism was 9.8% for no gland transplants, 11.9%, 15.1%, and 31.4% for 1,2,and 3 gland transplants, respectively (p < 0.05). The incidence of permanent hypoparathyroidism was 0.98%, 0.77%, 0.97%, and 0%, respectively (p = NS). The incidence of temporary hypoparathyroidism was higher when surgery was performed for Graves’ disease. Temporary hypocalcemia is closely related to the number of autotransplanted parathyroids during TT. The long-term outcome is not affected by the number of parathyroids autotransplanted. A “ready selective” approach to parathyroid autotransplantation is an effective strategy for minimizing the rate of permanent hypoparathyroidism.     

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.     

Hypoparathyroidism following total thyroidectomy: prognostic value of intraoperative parathyroid hormone assay

Transient and definitive hypoparathyroidism represent a frequent complication after thyroid surgery. Recently some authors proposed the use of intraoperative parathyroid hormone assay for the rapid detection of this complication. In this paper the authors describe the data obtained from 42 total thyroidectomies with intraoperative measurements of parathyroid hormone. When parathormone decrement was over 75% during thyroidectomy, the hypocalcemic symptomatology was found in all cases during postoperative observation. The authors emphasize intraoperative PTH dosage for immediate identification of patients at risk for postoperative hypoparathyroidism. In this cases parathyroid autotransplantation is suggested to prevent postoperative hypoparathyroidism.     

Parathyroid autotransplantation in total thyroidectomy

Although parathyroid autotransplantation during the course of thyroidectomy was first described by Halsted in 1907, it is only during the past 20 years that this simple and effective method of preserving parathyroid function is being used by an increasing number of surgeons. Our group has autotransplanted normal parathyroids since 1965, whenever these glands could not be preserved in situ with adequate blood supply. With increasing experience, we find it much simpler to autotransplant parathyroid glands attached to the thyroid, than to dissect their precarious blood supply, hoping they will survive postoperative edema and fibrosis. Furthermore, it is our impression that in operations for thyroid carcinoma, attempts to preserve the blood supply to the parathyroids may compromise the completeness of the thyroidectomy or of the dissection of cervical nodes in the tracheoesophageal groove. In a review of our experience during the past four years (January 1, 1984 to December 31, 1988), 87 patients underwent total thyroidectomy. Parathyroid glands that could not be saved in situ were biopsied to confirm their identity by frozen section and autotransplanted in the ipsilateral sternocleidomastoid muscle. Among the 87 patients undergoing total thyroidectomy, 34 required no autotransplantation, whereas 52 had one to three glands autotransplanted, and one had four glands autotransplanted. Postoperatively, 23 patients (26 percent) developed hypocalcemia, whereas 18 required CaCO3 and five required vitamin D in addition. All patients (98%) except two had normal parathyroid function at four-month follow-up and thereafter, as judged by serum calcium, phosphorus and parathormone, when indicated.     

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.     

Identification of Patients at Low Risk for Thyroidectomy-Related Hypocalcemia by Intraoperative Quick PTH

Background Transient hypoparathyroidism is a frequent and challenging complication following total thyroidectomy. The aim of the study was to identify patients at risk of developing thyroidectomy-related hypocalcemia and symptoms by means of the intraoperative quick parathyroid hormone (PTH) assay. Methods Eighty-one patients undergoing total thyroidectomy were included in the study. Quick PTH levels were measured at induction of anaesthesia and 10 minutes after total thyroidectomy. A sample of 10 patients who underwent unilateral thyroid lobectomy was considered as a control group. The accuracy of intraoperative PTH decline in predicting postoperative hypoparathyroidism was analysed. Results After total thyroidectomy, 27 patients (33.3%) developed postoperative hypocalcemia. Symptoms were reported by 21 patients (25.9%). The mean percentage decline of intraoperative quick PTH was 81% in hypocalcemic compared with 39% in normocalcemic patients (P < 0.001), and it was 83% in symptomatic compared with 42% in asymptomatic patients (P < 0.001). Mean proportion decline of quick PTH after unilateral lobectomy was 20%, significantly lower than the 53% registered after total thyroidectomy (P = 0.005). Analysis of variation of intraoperative quick PTH with the receiver operator characteristics (ROC) curve showed a 75.7% decline as the cut-off value predicting postoperative hypocalcemia with the highest accuracy (91.4%) (sensitivity: 81.5% specificity: 96.3% positive likelihood ratio: 22; negative likelihood ratio: 0.2). Regarding the prediction of postoperative symptoms, a 79.5% decline was the most accurate (92.6%) cut-off point (sensitivity: 76.2% specificity: 98.3% positive likelihood ratio: 46; negative likelihood ratio: 0.2). Conclusions Quick PTH monitoring during total thyroidectomy is a useful means for identifying low-risk patients for postoperative hypoparathyroidism and candidates for early, safe discharge. Furthermore, it is an objective method complementary to the surgeon’s judgement of the intraoperative function of parathyroid glands, which should be implanted in the event of a 75%–80% decline.