Superiority of continuous over intermittent intraoperative nerve monitoring in preventing vocal cord palsy.

BACKGROUND: Continuous intraoperative nerve stimulation (IONM) with uninterrupted monitoring is likely better than intermittent IONM in preventing vocal cord palsy after thyroid surgery. METHODS: This was a comparative study of intermittent versus continuous IONM in patients with benign and malignant thyroid disease treated at a tertiary centre over 10 years. Early postoperative and permanent vocal cord palsy rates were estimated. Multivariable logistic regression analysis was used to quantify the contributions of clinical and histopathological variables to early postoperative and permanent vocal cord palsy. RESULTS: A total of 6029 patients were included, of whom 3139 underwent continuous and 2890 intermittent IONM. Based on nerves at risk (5208 versus 5024 nerves), continuous IONM had a 1·7-fold lower early postoperative vocal cord palsy rate than intermittent monitoring (1·5 versus 2·5 per cent). This translated into a 30-fold lower permanent vocal cord palsy rate (0·02 versus 0·6 per cent). In multivariable logistic regression analysis, continuous IONM independently reduced early postoperative vocal cord palsy 1·8-fold (odds ratio (OR) 0·56) and permanent vocal cord palsy 29·4-fold (OR 0·034) compared with intermittent IONM. One permanent vocal cord palsy per 75·0 early vocal cord palsies was observed with continuous IONM, compared with one per 4·2 after intermittent IONM. Early postoperative vocal cord palsies were 17·9-fold less likely to become permanent with continuous than intermittent IONM. CONCLUSION: Continuous IONM is superior to intermittent IONM in preventing vocal cord palsy.

Targeted use of intraoperative frozen-section analysis lowers the frequency of completion thyroidectomy.

BACKGROUND: The impact of intraoperative frozen section (iFS) analysis on the frequency of completion thyroidectomy for the management of thyroid carcinoma is controversial. Although specialized endocrine centres have published their respective results, there are insufficient data from primary and secondary healthcare levels. The aim of this study was to analyse the utility of iFS analysis. METHODS: In the Prospective Evaluation Study Thyroid Surgery (PETS) 2 study, 22 011 operations for benign and malignant thyroid disease were registered prospectively in 68 European hospitals from 1 July 2010 to 31 December 2012. Group 1 consisted of 569 patients from University Medical Centre (UMC) Mainz, and group 2 comprised 21 442 patients from other PETS 2 participating hospitals. UMC Mainz exercised targeted but liberal use of iFS analysis for suspected malignant nodules. iFS analysis was compared with standard histological examination regarding the correct distinction between benign and malignant disease. The percentage of completion thyroidectomies was assessed for the participating hospitals. RESULTS: iFS analysis was performed in 35.70 per cent of patients in group 1 versus 21.80 per cent of those in group 2 (risk ratio (RR) 1.6, 95 per cent c.i. 1.5 to 1.8; P < 0.001). Sensitivity of iFS analysis was 75.0 per cent in group 1 versus 63.50 per cent in group 2 (RR 1.2, 1.2 to 1.3; P = 0.040). Completion surgery was necessary in 8.10 per cent of patients in group 1 versus 20.8 per cent of those in group 2 (RR 0.4, 0.2 to 0.7; P = 0.001). CONCLUSION: iFS analysis is a useful tool in determining the appropriate surgical management of thyroid disease. Targeted use of iFS was associated with a significantly higher sensitivity for the detection of malignancy, and with a significantly reduced necessity for completion surgery.

Twenty-year experience of paediatric thyroid surgery using intraoperative nerve monitoring.

BACKGROUND: There are few data on intermittent and continuous intraoperative nerve monitoring (IONM) during thyroidectomy in children. METHODS: All children aged 18 years or younger who had standard thyroid operations using intermittent or continuous IONM between January 1998 and December 2016 were included in the study. The impact of age and type of IONM on basal amplitude, latency and complications after thyroidectomy were assessed. RESULTS: A total of 504 children were included in the study. With continuous IONM, median basal amplitude and latency increased significantly with age, more on the left side (from 199 to 870 µV, and from 3·88 to 5·75 ms) than on the right (from 340 to 778 µV, and from 2·63 to 3·50 ms). Compared with intermittent IONM with needle electrode, continuous IONM with tube electrode resulted in an increase in median basal amplitude in children aged 13-18 years on both sides (from 675 to 778 µV on the right and from 450 to 870 µV on the left), and a decrease in median latency in all children older than 3 years: in children aged 4-6 years, from 4·20 to 3·00 ms on the right and from 6·10 to 4·63 ms on the left; in children aged 7-12 years, from 4·60 to 3·50 ms and from 6·00 to 5·25 ms respectively; and in children aged 13-18 years, from 4·60 to 3·50 ms and from 6·40 to 5·75 ms. Overall, wound infection, but not bleeding/haematoma or vocal fold palsy, affected younger children more: 3 per cent of children aged 3 years or less; 2 per cent of children aged 4-6 years; and 0 per cent of children aged over 6 years (P = 0·031). With continuous IONM, no wound infection, bleeding/haematoma or permanent vocal fold palsy was noted in any age group. CONCLUSION: Continuous IONM measures nerve electrophysiology more accurately than intermittent IONM during thyroidectomy in children.

Risk profile analysis and complications after surgery for autoimmune thyroid disease.

BACKGROUND: Surgical approaches to autoimmune thyroid disease are currently hampered by concerns over postoperative complications. Risk profiles and incidences of postoperative complications have not been investigated systematically, and studies with sufficient power to show valid data have not been performed. METHODS: A prospective multicentre European study was conducted between July 2010 and December 2012. Questionnaires were used to collect data prospectively on patients who had surgery for autoimmune thyroid disease and the findings were compared with those of patients undergoing surgery for multinodular goitre. Logistic regression analysis was used to evaluate risk factors for thyroid surgery-specific complications, transient and permanent recurrent laryngeal nerve (RLN) palsy and hypoparathyroidism. RESULTS: Data were available for 22 011 patients, of whom 18 955 were eligible for analysis (2488 who had surgery for autoimmune thyroid disease and 16 467 for multinodular goitre). Surgery for multinodular goitre and that for autoimmune thyroid disease did not differ significantly with regard to general complications. With regard to thyroid surgery-specific complications, the rate of temporary and permanent vocal cord palsy ranged from 2·7 to 6·7 per cent (P = 0·623) and from 0·0 to 1·4 per cent (P = 0·600) respectively, whereas the range for temporary and permanent hypoparathyroidism was 12·9 to 20·0 per cent (P < 0·001) and 0·0 to 7·0 per cent (P < 0·001) respectively. In logistic regression analysis of transient and permanent vocal cord palsy, autoimmune thyroid disease was not an independent risk factor. Autoimmune thyroid disease, extent of thyroid resection, number of identified parathyroid glands and no autotransplantation were identified as independent risk factors for both transient and permanent hypoparathyroidism. CONCLUSION: Surgery for autoimmune thyroid disease is safe in comparison with surgery for multinodular goitre in terms of general complications and RLN palsy. To avoid the increased risk of postoperative hypoparathyroidism, special attention needs to be paid to the parathyroid glands.

Expression of ARE-binding proteins AUF1 and HuR in follicular adenoma and carcinoma of thyroid gland.

Both adenylate-uridylate rich elements binding proteins AUF1 and HuR may participate in thyroid carcinoma progression. In this study we investigated the expression of both factors on a protein level with a special focus on follicular adenoma and follicular thyroid carcinoma. By employment of immunofluorescence and western blot on 68 thyroid tissues including 7 goiter, 16 follicular adenoma (4 adenomatous hyperplasia), 19 follicular thyroid carcinomas, 13 papillary thyroid carcinomas and 14 undifferentiated thyroid carcinomas we investigated protein expression of AUF1 and HuR. In addition to previous results we demonstrated that AUF1 and HuR are significantly up-regulated in carcinoma tissues as compared with follicular adenoma or goiter tissues. Furthermore, by evaluation of AUF1 or HuR expression, or combination of both proteins on total tissue lysates, we were able to demonstrate a significant difference between follicular adenoma and follicular thyroid carcinoma. Overexpression of AUF1 and HuR is a common finding observed in thyroid malignancy. Analysis of the tissues obtained by surgical resection as demonstrated in this study is comparable to a fine needle aspiration and in combination with AUF1/HuR immuno-analysis may support the conventional immunohistological investigations. The promising results of this study were performed on relatively small collective, but justify future development of a quick thyroid diagnostic test on larger cohort of the patients, especially for thyroid samples which are inadequate for histological examinations.

Postoperative vocal fold palsy in patients undergoing thyroid surgery with continuous or intermittent nerve monitoring.

BACKGROUND: Continuous monitoring of electromyographic (EMG) amplitudes of the vocal muscles detects impending injury of the recurrent laryngeal nerve (RLN) during thyroid operations earlier than intermittent EMG monitoring. This may alert the surgeon to stop a manoeuvre causing stretching or pressure on the RLN, with better recovery of nerve function. METHODS: Patients with intact preoperative RLN function who underwent thyroid surgery for benign disease between January 2011 and September 2014 under continuous intraoperative nerve monitoring (CIONM) or intermittent intraoperative nerve monitoring (IIONM) were included in this observational study conducted at a tertiary surgical centre. For CIONM, combined EMG events indicative of imminent nerve injury were defined as an EMG amplitude decrease of 50 per cent or more and a latency increase of 10 per cent relative to baseline values. The rates of early and permanent palsy for the two groups of patients were compared. RESULTS: There were 1526 patients, 788 of whom (1314 nerves at risk) underwent thyroid surgery using CIONM and 738 (965 nerves at risk) had IIONM. With the use of CIONM, 63 (82 per cent) of 77 combined events were reversible during the operation. No permanent vocal fold palsy occurred with CIONM, whereas four unilateral permanent vocal fold palsies (0·4 per cent) were diagnosed after IIONM (P = 0·019). CONCLUSION: Operation with CIONM resulted in fewer permanent vocal fold palsies compared with IIONM after thyroid surgery in patients with benign disease.

[Vocal cord paralysis after thyroid surgery : Current medicolegal aspects of intraoperative neuromonitoring]. / Stimmlippenparesen nach Schilddrüsenoperationen : Aktuelle medikolegale Aspekte des intraoperativen Neuromonitorings.

Intraoperative neuromonitoring (IONM) has been commercially available for approximately 15 years and is highly predictive in thyroid gland surgery concerning either postoperative vocal fold mobility in the case of an intact signal for muscle action electromyogram (EMG, > 99 % right negative) or vocal fold dysfunction in the case of loss of signal (> 70 % right positive). The use of IONM improves the intraoperative identification of recurrent laryngeal nerve function and due to the high predictive value with respect to the expected vocal cord function the result of IONM has to be integrated into the surgical concept of thyroidectomy. Unilateral loss of function of the recurrent laryngeal nerve cannot be completely avoided despite correct application of IONM; however, bilateral vocal fold palsy can be safely avoided when contralateral surgery is cancelled after a loss of signal occurs during resection of the first side in planned bilateral surgery (alternative strategy). Patients have to be informed preoperatively about the limitations of IONM and potential strategy changes during planned bilateral surgery. Surgeons should apply IONM according to the published current recommendations and by selecting a risk-oriented intraoperative strategy in the case of loss of signal from the recurrent laryngeal nerve.

[Management of postoperative hemorrhage following thyroid surgery]. / Management von Nachblutungen nach Schilddrüsenoperationen.

The incidence of postoperative hemorrhage following thyroid surgery stands at 1%-2 %. This low incidence contrasts with the significant potential complications of postoperative hemorrhage. Influencing factors and measures mentioned in the literature and own studies are discussed. Although an improvement in the postoperative hemorrhage rate was to be expected indirectly due to the increasing use of coagulation-relevant medication, there has been neither an increase in incidence nor a reduction in resultant complications, including primarily recurrent vocal cord paresis, tracheotomy and mortality. Factors that influence surgical success include a meticulous technique and caution, as well as ensuring intensive and qualified postoperative monitoring for a minimum of 4-6 h, thereby permitting immediate revision surgery at any time.

[Surgical strategy during intended total thyroidectomy after loss of EMG signal on the first side of resection]. / Operative Strategie bei geplanter totaler Thyreoidektomie und Verlust des Neuromonitoring-Signals auf der erstoperierten Seite.

BACKGROUND: Unambiguous identification of the recurrent laryngeal nerve with detection of nerve dysfunction giving rise to postoperative vocal cord palsy (VCP) is the principal objective of intraoperative neuromonitoring (IONM) in thyroid surgery. Because intraoperative loss of the electromyographic (EMG) signal (LOS) does not result in VCP in one third of patients, controversy surrounds the issue of whether a change in strategy is needed in planned total thyroidectomy after LOS on the first side of resection. PATIENTS AND METHODS: This was a retrospective institutional study of 1,049 consecutive patients (2,086 nerves at risk) with intended bilateral thyroid surgery who were operated on between April 2010 and July 2012 with the use of IONM. The rates of temporary and permanent VCP were analyzed on the basis of the IONM results of the first side of resection and the extent of contralateral resection for completion: resection without LOS (group 1); resection with LOS and contralateral thyroidectomy (group 2); resection with LOS and contralateral subtotal resection (group 3); resection with LOS without any contralateral resection (group 4). RESULTS: LOS on the first side of resection was noted in 27 patients (2.6 %). All VCPs were unilateral. The rates of temporary and permanent VCP were 2.5 and 0.4 %, respectively, overall; specifically: group 1: 0.5 and 0 %; group 2: 64 and 9.1 %; group 3: 100 and 50 %; group 4: 83 and 8.3 %, respectively. CONCLUSION: Because an abnormal intraoperative electromyogram carries an 80 % risk for early postoperative VCP, the initial plan of bilateral surgery needs to be critically reviewed after LOS has occurred on the first side of resection, taking into account the underlying thyroid disease of the patient and surgeon expertise. Since more than 80 % of affected nerves will fully recover after the operation, staged completion thyroidectomy is recommended.

[Surgery for benign goiter in Germany: fewer operations, changed resectional strategy, fewer complications]. / Strumachirurgie in Deutschland: Weniger Operationen, geänderte Resektionsstrategien, weniger Komplikationen.

BACKGROUND: The increase of certain operations in the wake of the introduction of the German Diagnosis-Related Groups (G-DRG) system rekindled debate on the risk-benefit profile of what is widely being perceived as a too high number of thyroidectomies for benign goiter in Germany. MATERIAL AND METHODS: The numbers of thyroidectomy for benign goiter from 2005-2011 were obtained from the Federal Bureau of Statistics ("Statistisches Bundesamt"). For the purpose of the study, the following operation and procedure key (OPS) codes were selected: hemithyroidectomy (OPS code 5-061); partial thyroid resection (OPS code 5-062); total thyroidectomy (OPS code 5-063); and thyroid surgeries via sternotomy (OPS code 5-064). The rates of permanent hypoparathyroidism and vocal cord palsy were calculated based on two prospective multicenter evaluation studies conducted in 1998-2001 (PETS 1) and 2010-2013 (PETS 2) in Germany. RESULTS: Between 2005 and 2011, the number of thyroidectomies for benign thyroid goiter decreased by 8 %, and the age-standardized surgery rate decreased by 6 % in men (2005: 599 per 1 million; 2011: 565 per 1 million) and 11 % in women (2005: 1641 per 1 million; 2011: 1463 per 1 million). At the same time, the rates of partial and subtotal thyroidectomy decreased by 59 % in men and 64 % in women, whereas the rates of hemithyroidectomy and total thyroidectomy increased by 65 % (113 %) in men and 42 % (97 %) in women. Despite a greater proportion of thyroidectomies over time, the approximated rates for postoperative hypoparathyroidism were reduced from 2.98 to 0.83 % and for postoperative vocal cord palsy from 1.06 to 0.86 %. Irrespective of that decline, either complication was more frequent after total than after subtotal thyroidectomy. CONCLUSION: The total number of thyroid surgeries due to benign goiter has decreased substantially in Germany from 2005 through 2011. Despite changes in the resectional strategy with an increase in the total number thyroidectomies and a decrease of subtotal resections, the rates for postoperative hypoparathyroidism and vocal cord palsy have decreased. The complication rates for total thyroidectomy, however, are still higher compared to subtotal resection. An individualized risk-oriented surgical approach is warranted.

[Surgical management of renal hyperparathyroidism]. / Chirurgisches Management des renalen Hyperparathyreoidismus.

Conservative management of renal hyperparathyroidism has changed recently. Innovative substances, especially the advent of calcimimetics, have influenced the therapeutic concept. Consequently, a decline in surgical frequency for renal hyperparathyroidism has been reported. In this context it is now mandatory to evaluate the role of surgery, the surgical strategy and procedures for renal hyperparathyroidism anew. Based on a review of the literature the current position of surgical indications and care for renal hyperparathyroidism as well as possible influences of innovative medical treatment are highlighted. In summary, the timing and indications for surgery have been influenced, however, surgery still remains the only permanently effective treatment option for renal hyperparathyroidism.

[Endocrine surgery for neck paraganglioma: operation, radiation therapy or wait and scan?]. / Endokrine Chirurgie zervikaler Paragangliome: Operation, Strahlentherapie oder "wait and scan"?

BACKGROUND: Head and neck paraganglioma (HNP) represent rare endocrine tumors. Therapy is decided on genetic findings, tumor characteristics (e.g. tumor size, localization and dignity), age of patient and symptoms. In terms of local control radiation therapy is as equally effective as surgery but surgical morbidity rates secondary to cranial nerve injuries remain high. PATIENTS: Based on 6 patients with 11 solitary (4 patients) and multiple (2 patients) HNP (8 carotid body tumors, 1 vagal, 1 jugular and 1 jugulotympanic paraganglioma) the specific characteristics of the need for surgery as well as correct choice of treatment in cases of sporadic succinate dehydrogenase (SDH) negative and hereditary SDH positive HNP will be exemplarily demonstrated. RESULTS: A total of 6 carotid body tumors (four sporadic, two hereditary) were resected in 4 patients, five as primary surgery and one as a revision procedure. In one case a preoperative embolization was performed 24 h before surgery. Malignancy could not be proven in any patient. The 30-day mortality was zero. In the patient with bilateral hereditary carotid body tumors, unilateral local recurrent disease occurred. After resection of the recurrent tumor permanent unilateral paralysis of the laryngeal nerve, glossopharyngeal nerve and hypoglossal nerve occurred. All patients were followed-up postoperatively for a mean of 64 months (range 23-78 months) with a local tumor control rate of 100%. The overall survival rate after 5 years was 100%. CONCLUSIONS: Given a very strict indication with awareness of surgical risks selective surgery has a key position with low postoperative morbidity in the treatment of HNPs. We prefer surgery for small unilateral paraganglioma, malignant or functioning tumors.

Loss of the nerve monitoring signal during bilateral thyroid surgery.

BACKGROUND: This study aimed to assess current use of recurrent laryngeal nerve monitoring (RLNM) for bilateral thyroid surgery in Germany. It explored the willingness of surgeons to change strategy after loss of signal (LOS) on the first side of resection. METHODS: Surgical departments in Germany equipped with nerve monitors were asked to complete a structured questionnaire, specifying the number of thyroidectomies done in 2010, and the frequencies of RLNM, vagal stimulation, and electromyographic (EMG) recording before and after thyroidectomy. They were also asked about the surgical plan for bilateral goitre after LOS on the first side of resection. RESULTS: Based on manufacturers' sales data, 1119 (89·1 per cent) of 1256 surgical departments in Germany were equipped with nerve monitors in 2010. A total of 595 departments (53·2 per cent), accounting for approximately 75 per cent of all thyroidectomies in Germany during that year, returned a completed questionnaire. RLNM was used in 91·7-93·5 per cent of thyroidectomies, with the addition of routine vagal stimulation in 49·3 per cent before, and 73·8 per cent after resection. EMG responses to vagal stimulation were recorded in 54·8 per cent before, and 72·5 per cent after resection. Some 93·5 per cent of surgeons changed the resection plan for the other side in bilateral thyroid surgery after LOS had occurred on the first side. CONCLUSION: RLNM is now the standard of care during thyroidectomy in Germany. After LOS on the first side of resection in bilateral goitre, more than 90 per cent of respondents declared their willingness to change the resection plan for the contralateral side to avoid the risk of bilateral recurrent laryngeal nerve palsy.

[Current TNM system of the UICC/AJCC : the prognostic significance for differentiated thyroid carcinoma]. / Aktuelles TNM-System der UICC/AJCC : Prognostische Bedeutung beim differenzierten Schilddrüsenkarzinom.

BACKGROUND: The aim of study was an evaluation of prognostic factors of the current TNM version (UICC/AJCC 2009, 7th revision) for differentiated thyroid carcinoma (DTC). PATIENTS AND METHODS: A total of 368 patients with DTC (papillary thyroid carcinoma [PTC] n = 269, follicular thyroid carcinoma [FTC] n = 99) were included. Disease-specific survival (DSS) was calculated based on the different TNM stages (mean follow-up 60 ± 37.5 months). RESULTS: When compared to patients with FTC, PTC patients had smaller tumors (diameter 19 mm versus 33 mm), more often lymph node metastases (40.9% versus 9.1%) but less frequent distant metastases (2.6 versus 13.1%) and poorly differentiated variants (PDTC 3.0% versus 8.1%). The 5-year and 10-year DSS for PTC versus FTC were 97.3% versus 91.5% and 96.2% versus 91.5% (p = 0.086), respectively. When comparing different TNM categories between well-differentiated PTC and FTC, no statistically significant differences were found but PDTCs, had a significantly worse DSS. CONCLUSIONS: The current TNM system is a sufficient tool for predicting DSS in well-differentiated PTC. In FTC, the extent of capsular and vascular invasion should also be considered. The implementation of a specific TNM system for PDTC needs to be confirmed in further studies.

Intraoperative monitoring of the recurrent laryngeal nerve in thyroid surgery.

BACKGROUND: Recurrent laryngeal nerve (RLN) palsy ranks among the leading reasons for medicolegal litigation of surgeons because of its attendant reduction in quality of life. As a risk minimization tool, intraoperative nerve monitoring (IONM) has been introduced to verify RLN function integrity intraoperatively. Nevertheless, a systematic evidence-based assessment of this novel health technology has not been performed. METHODS: The present study was based on a systematic appraisal of the literature using evidence-based criteria. RESULTS: Recurrent laryngeal nerve palsy rates (RLNPR) varied widely after thyroid surgery, ranging from 0%-7.1% for transient RLN palsy to 0%-11% for permanent RLN palsy. These rates did not differ much from those reported for visual nerve identification without the use of IONM. Six studies with more than 100 nerves at risk (NAR) each evaluated RLNPR by contrasting IONM with visual nerve identification only. Recurrent laryngeal nerve palsy rates tended to be lower with IONM than without it, but this difference was not statistically significant. Six additional studies compared IONM findings with their corresponding postoperative laryngoscopic results. Those studies revealed high negative predictive values (NPV; 92%-100%), but relatively low and variable positive predictive values (PPV; 10%-90%) for IONM, limiting its utility for intraoperative RLN management. CONCLUSIONS: Apart from navigating the surgeon through challenging anatomies, IONM may lend itself as a routine adjunct to the gold standard of visual nerve identification. To further reduce the number of false negative IONM signals, the causes underlying its relatively low PPV require additional clarification.

[Thyroid surgery: generalist or specialist?]. / Schilddrüsenchirurgie: Generalist oder Spezialist?

BACKGROUND: Thyroid surgery is done in Germany in a considerable numbers of operations (about 110,000 per year). To perform thyroid operations by so called "generalists" or "specialists" have been discussed intensively, however, this issue have not been analyzed in detail. METHODS: Study material comprised 16,500 consecutive thyroid operations with 30,000 operated sites that have been prospectively documented in the German Thyroid Multicenter Study performed 1998 through 2001. Quality of surgery were analyzed by calculating the inverse relationship between volume and outcome (complication rate). RESULTS: To achieve complication rates (permanent unilateral recurrent laryngeal nerve paralysis and hypocalcemia) of < 1 % (primary surgery) or < 3 % (redo surgery) the minimum number of thyroid operations of lower level of experience (e. g. benign nodular goiter) per year was n=30. The minimum number of operations with higher level of experience was significantly lower (n=3-12) due to the higher level of experience of operating surgeons. In contrast to the rates of postoperative hypocalcemia the rates of postoperative recurrent laryngeal nerve paralysis was clearly related to the number of thyroid operations performed. CONCLUSIONS: The high number of thyroid operations in Germany with about 20 % of operations of high level experience are requiring surgical curricula and hospital structures that offer as well generalists as specialists to treat the broad spectrum of thyroid diseases accordingly. To lower the complication rate especially of difficult thyroid operations the level of specialization in Germany have to be increased.

[Not all vocal cord failure following thyroid surgery is recurrent paresis due to damage during operation. Statement of the German Interdisciplinary Study Group on Intraoperative Neuromonitoring of Thyroid Surgery concerning recurring paresis due to intubation]. / Nicht jeder Stimmlippenstillstand nach Schilddrüsenoperation ist eine chirurgischbedingte Rekurrensparese. Stellungnahme der "Interdisziplinären Studiengruppe Intraoperatives Neuromonitoring Schilddrüsenchirurgie" zur Problematik intubationsbedingter Rekurrensparesen.

Since the phoniatrician H. Bauer described the first case of recurrent laryngeal nerve palsy most likely caused by intubation some 45 years ago, several case reports have been published. However, systematic analyses regarding the frequency of recurrent laryngeal nerve palsies due to intubation are scarce, and none of them has used the proper methods to demonstrate clearly that such a mechanism exists. Currently available data justify the assumption that not every recurrent laryngeal nerve palsy following thyroid surgery is due to the operation itself and that the damage caused by intubation, however, may only account for a minority of these cases. The differential diagnosis of postoperative recurrent laryngeal nerve palsy requires the use of specific tools which go beyond simple laryngoscopy and include stroboscopy as well as intra- and extralaryngeal electromyography. A partial palsy of recurrent laryngeal nerve due to intubation would be associated with severe dysphonia or aphonia, not with dyspnea because of the typical intermediate position of the paralyzed vocal folds with a normal electromyographic function of the cricothyroid muscle. The use of these methods to identify the nature of postoperative recurrent laryngeal nerve palsy is recommended in cases of regular intraoperative neuromonitoring but postoperatively impaired function of the vocal cords.

[Effectiveness and results of intraoperative neuromonitoring in thyroid surgery. Statement of the Interdisciplinary Study Group on Intraoperative Neuromonitoring of Thyroid Surgery]. / Zuverlässigkeit und Konsequenzen des intraoperativen Neuromonitorings in der Schilddrüsenchirurgie. Stellungnahme der "Interdisziplinären Studiengruppe Intraoperatives Neuromonitoring Schilddrüsenchirurgie"

Intraoperative neuromonitoring (IONM) has yielded an increasing effect on thyroid surgery. During IONM, the recurrent laryngeal nerve is stimulated electrically and an acoustically transformed electromyographic signal is derived via either a needle electrode placed in the vocalis muscle or an electrode adjusted to the intubation tube. The IONM is used for identifying and predicting the function of the recurrent laryngeal nerve. Especially under difficult anatomic conditions, IONM has proven a valuable tool for identification of recurrent laryngeal nerves. This can lead to decreased occurrence of nerve palsy rates, as shown in numerous studies. The reliability of the IONM signal (defined as the correlation between intraoperative signal interpretation and postoperative vocal cord function) is reflected by a specificity as high as 98.2%, as shown by German multicenter studies. Thus, normal vocal cord function could be demonstrated postoperatively in over 98.2% of patients with intraoperatively unchanged neuromonitoring signals. If the neuromonitoring signal changed during operation, 39% of the patients suffered from transient vocal cord immobility and 12% had permanent loss of vocal cord function.

[Ambulatory and brief inpatient thyroid gland and parathyroid gland surgery]. / Ambulante und kurzzeitstationäre Schilddrüsen- und Nebenschilddrüsenchirurgie.

Outpatient or short-stay thyroid and parathyroid surgery is still uncommon in Germany. Although a substantial number of these operations are performed with low morbidity, nearly zero mortality, and short operation time, some potentially lethal complications, especially postoperative hemorrhage, are strong arguments against liberal shortening of hospital stay. Symptomatic hematomas after thyroid and parathyroid surgery are observed in about 1-2% of cases. They frequently occur during the first 8 h after operation (40%). However, two thirds of these major complications occur later, about 20% of them more than 24 h postoperatively. Therefore, an outpatient procedure cannot be generally recommended. Short-stay (<23 h, overnight) thyroid and parathyroid surgery may be attractive, but this concept requires clear release-criteria and professional outpatient structures. Compared to general anesthesia, local and regional anesthesia did not emerge as helpful to shorten hospital stay. Also, prophylactic calcium supplementation is not recommended to enhance early hospital discharge after bilateral thyroid or parathyroid surgery.

[Is primary total thyroidectomy justified in benign multinodular goiter? Results of a prospective quality assurance study of 45 hospitals offering different levels of care]. / Rolle der totalen Thyreoidektomie im primären Therapiekonzept der benignen Knotenstruma. Ergebnisse einer prospektiven Qualitätssicherungsstudie in 45 Kliniken unterschiedlicher Versorgungsstufen.

INTRODUCTION: After subtotal resection of multinodular goiter, rates of up to 40% are reported for recurrent goiter in the long-term follow-up. Because of the increased morbidity of surgery for recurrent goiter, this study evaluated the preconditions that would justify total thyroidectomy as part of the primary therapy concept for benign multinodular goiter. MATERIAL AND METHODS: The Quality Assurance Study of Benign and Malignant Goiter covering the period from 1 January to 31 December 1998 assessed 5195 patients treated for benign goiter by primary bilateral resection. With respect to the extent of resection three groups were analyzed: bilateral subtotal resection (ST+ST, n=4580), subtotal resection with contralateral lobectomy (ST+HT, n=527), and total thyroidectomy (TT, n=88). RESULTS: The age of the patients was significantly higher (60.3 years) in the TT group than in the ST+ST (52.5 years) and ST+HT (55.6 years) groups. ASA classification grades III and IV were significantly more frequent in the TT group. The postoperative morbidity increased with the extent of resection. The rate of permanent recurrent laryngeal nerve (RLN) palsy was 0.8% for ST+ST, 1.4% for ST+HT, and 2.3% for TT and of permanent hypoparathyroidism 1.5% for ST+ST, 2.8% for ST+HT, and 12.5% for TT. Multivariate analysis showed that the extent of resection significantly increased the risk of RLN palsy (transient RR 0.5, permanent RR 0.4) and hypoparathyroidism (transient RR 0.2,permanent RR 0.08). The surgeon's experience (RR 0.6) and identification of the RLN (RR 0.5) reduced the risk of permanent RLN palsy. Additionally, the development of permanent hypoparathyroidism was reduced if at least two parathyroid glands (RR 0.4) were identified. CONCLUSION: Total thyroidectomy is associated with an increased rate of RLN palsies and hypoparathyroidism in comparison to less extensive thyroid surgery. In the hands of well-trained surgeons using an appropriate intraoperative technique, primary thyroidectomy is justified if the patient has an increased risk of recurrent goiter. Due to the increased postoperative morbidity after total thyroidectomy, subtotal thyroid resection based on the morphologic changes in the thyroid gland is still recommended as the standard treatment regimen for multinodular goiter.