; Chirurgische Arbeitsgemeinschaft Endokrinologie (CAEK) der Deutschen Gesellschaft für Allgemein- und Viszeralchirurgie (DGAV) und für die Deutsche Gesellschaft für Chirurgie (DGCH). Rekurrens- und Nebenschilddrüsenpräparation in der Schilddrüsenchirurgie

Factors predicting hypocalcemia after total thyroidectomy - A retrospective cohort analysis

BACKGROUND

Hypocalcemia after total thyroidectomy is the most frequent complication resulting in prolongation of hospitalisation. Therefore we aimed to analyse clinical risk factors predictive for hypocalcemia and its long term persistence after total thyroidectomy.

METHODS

Retrospective analysis of patients undergoing total thyroidectomy from 2005 until 2013. Outcome measures were initial postoperative hypocalcemia defined as serum calcium below 2.0 mmol/l after total thyroidectomy within 48 h and persistent hypocalcemia defined as serum calcium below 2.0 mmol/l above six months and/or the need for additional calcium and vitamin D supplementation.

RESULTS

Initial postoperative hypocalcemia was present in 160 of 702 patients (22.8%) with 91 patients (13%) developing symptoms. 48 patients (6.8%) had a persistent hypocalcemia above six months. Patients with an initial symptomatic postoperative hypocalcemia showed significantly more often a persistent hypocalcemia compared to asymptomatic patients with biochemical hypocalcemia (38 patients (41.8%) vs. 10 patients (14.5%), p < 0,001). In the binary logistic regression analysis, female gender (OR 2.4; CI95% 1.5-3.8), prolonged surgery time >189 min (OR 1.8; CI95% 1.2-2.6) and parathyroid reimplantation (OR 2.4; CI95% 1.2-4.7) were associated with initial hypocalcemia while only initial symptomatic hypocalcaemia was shown to be independently associated with persistent hypocalcemia (OR 40.9; CI95% 18.5-90.4).

CONCLUSION

Prolonged surgery time seems to correlate with initial postoperative hypocalcemia independently of the underlying disease and surgical expertise but does not affect the persistence of hypocalcemia. Initial symptomatic postoperative hypocalcemia after total thyroidectomy is associated with a high rate of persistent hypocalcemia.

The Anastomoses of the Recurrent Laryngeal Nerve in the Larynx: A Meta-Analysis and Systematic Review

OBJECTIVES

The recurrent laryngeal nerve and its branches form a great variety of anastomoses. These nerve communications can alter the innervation patterns of the laryngeal muscles and can affect both the diagnosis and treatment of paralyzed vocal cords. The aim of this study was to assess the prevalence and anatomical characteristics of the laryngeal nerve connections, and to review their function and clinical significance.

STUDY DESIGN

Meta-analysis and systematic review.

METHODS

The major electronic databases were thoroughly searched to identify all studies reporting data on the anastomoses of the laryngeal nerves. Data on the prevalence of each type of anastomosis were extracted and pooled into a meta-analysis using MetaXL version 3.0 (EpiGear International Pty. Ltd., Wilston, Queensland, Australia).

RESULTS

Twenty-two cadaveric studies (n = 1404 hemilarynges) were included in the meta-analysis. The two most common communications were Galen's anastamosis and the arytenoid plexus. The pooled prevalence estimate for Galen's anastamosis was 76.7% (95% confidence interval [CI]: 59.0-90.0), of which the single trunk type was most common (92.3%). The arytenoid plexus had a pooled prevalence estimate of 79.7% (95% CI: 41.1-100).

CONCLUSIONS

Owing to the high prevalences and variability of nerve connections in the larynx, detailed anatomical knowledge of these anastomoses can be crucial for the accurate interpretation of laryngoscopy results, reducing iatrogenic injury during surgical procedures, and facilitating the development of novel strategies for treating laryngeal paralyses.

[Surgical assessment of complications after thyroid gland operations]

BACKGROUND

The extent, magnitude and technical equipment used for thyroid surgery has changed considerably in Germany during the last decade. The number of thyroidectomies due to benign goiter have decreased while the extent of thyroidectomy, nowadays preferentially total thyroidectomy, has increased. Due to an increased awareness of surgical complications the number of malpractice claims is increasing.

OBJECTIVES

In contrast to surgical databases the frequency of complications in malpractice claims reflects the individual impact of complications on the quality of life. In contrast to surgical databases unilateral and bilateral vocal fold palsy are therefore at the forefront of malpractice claims. As guidelines are often not applicable for the individual surgical expert review, the question arises which are the relevant criteria for the professional expert witness assessing the severity of the individual complication.

RESULTS

While in surgical databases major complications after thyroidectomy, such as vocal fold palsy, hypoparathyroidism, hemorrhage and infections are equally frequent (1-3 %), in malpractice claims vocal fold palsy is significantly more frequent (50 %) compared to hypoparathyroidism (15 %), hemorrhage and infections (about 5 % each). To avoid bilateral nerve palsy intraoperative nerve monitoring has become of utmost importance for surgical strategy and malpractice suits alike. For surgical expert review documentation of individual risk-oriented indications, the surgical approach and postoperative management are highly important.

CONCLUSION

Guidelines only define the treatment corridors of good clinical practice. Surgical expert reviews in malpractice suits concerning quality of care and causality between surgical management, complications and sequelae of complications are therefore highly dependent on the grounds and documentation of risk-oriented indications for thyroidectomy, intraoperative and postoperative surgical management.

[Bilateral vocal cord paresis after total thyroidectomy]

A 66-year-old female patient complained of hoarseness and dyspnea under exertion following total thyroidectomy. Due to a faulty operating technique both nerves to the vocal cords were damaged. From the operation report it emerged that the dissection was carried out by protecting the border lamellae but the recurrent laryngeal nerve could not be found on both sides. This article presents the external expert opinion, the decision of the arbitration board and the assessment of the case by two specialist physicians.

[Intraoperative avoidance and recognition of recurrent laryngeal nerve palsy in thyroid surgery]

Recurrent laryngeal nerve palsy is an intrinsic complication of thyroid surgery. Prevention of nerve palsy is considered to be a feature of quality in this very frequently performed operation. Risk factors and prevention strategies are demonstrated and discussed with reference to the current literature. Exact knowledge of the anatomy and possible variants of the track of the recurrent laryngeal nerve as well as its visualization and careful dissection are the cornerstones for nerve preservation. The use of intraoperative neuromonitoring allows preservation of the anatomical structure and functional integrity of the nerve and lesions which are not visible can be detected. Preconditions for correct interpretation are a standardized application and preoperative and postoperative laryngoscopy.

[Minimally invasive video-assisted thyroidectomy: establishment in a thyroid center]

BACKGROUND

This study retrospectively evaluated a series of patients who underwent minimally invasive video-assisted thyroidectomy (MIVAT) during the introduction stage of this surgical technique at the Martha-Maria Hospital in Nuremberg.

PATIENTS AND METHODS

The eligibility criteria for MIVAT were a thyroid volume < 25 ml, nodules < 30 mm, no thyroiditis, no preoperative evidence of carcinoma and no previous neck surgery. A retrospective evaluation was performed together with a control group of patients who underwent conventional thyroid surgery during the same time period and included a follow-up for general patient satisfaction and cosmetic results.

RESULTS

Between August 2008 and July 2009 a total of 55 patients underwent MIVAT including 8 conversions to open surgery and 45 patients who underwent conventional surgery served as matched controls. No significant differences in terms of perioperative complication rates were found (e.g. recurrent laryngeal nerve palsy, hypocalcemia or secondary hemorrhage). The mean operating time was significantly longer in the MIVAT group (96.8 ± 3.7 min vs. 69.8 ± 2.3 min, p = 0.001) whereas a significant decrease in the mean operating time for hemithyroidectomy after 5 months was observed (98.1 ± 3.77 min vs. 76.0 ± 4.98 min, p = 0.013). Patients in the MIVAT group were more satisfied with the cosmetic outcome (8.5 ± 0.3 vs. 8.2 ± 0.2, p = 0.05) as well as with the overall surgical procedure (9.0 ± 0.3 vs. 8.6 ± 0.2, p = 0.02).

CONCLUSION

During introduction of the MIVAT procedure a learning effect can be observed which is hallmarked by a decrease in operating time and conversion rate to open surgery. Moreover, no significant differences in terms of main postoperative complications were found so that MIVAT can be considered a safe and feasible technique under the conditions of correct eligibility criteria.

Can a surgeon predict the risk of postoperative hypoparathyroidism during thyroid surgery? A prospective study on self-assessment by experts

BACKGROUND

Thyroid surgery can cause postoperative hypocalcemia (POH) and permanent hypoparathyroidism (PEH). Surgeons implicitly assess the risk and adapt their surgical strategy accordingly.

METHODS

The outcome of this intraoperative decision-making process (the surgeons' ability to predict the risk of POH and PEH on a numerical rating scale and their actual incidence) was studied prospectively in 2,558 consecutive thyroid operations.

RESULTS

POH and PEH occurred in 723 and 64 patients, respectively. In multivariate analysis, the surgeons' risk assessment score was an independent predictive factor for both complications (P < .05). Surgeons' differed significantly (P = .015) in their rates of POH but not of PEH (P = .062). Six and 3 (of 9) surgeons correctly predicted an increased risk of PEH and POH (adjusted odds ratios 1.67 to 2.21 and 1.47 to 12.73), respectively.

CONCLUSION

The risk for hypoparathyroidism can be estimated, but surgeons differ substantially in this ability and in the extent to which this implicit knowledge is translated into lower complication rates.

[Intraoperative complications of neck surgery]

Intraoperative complications of neck surgery are uncommon and rarely life-threatening and exact anatomical knowledge and precise dissection are most important for prevention. Anatomical variants (e.g. non-recurrent nerve, extralaryngeal branching) predispose to damage of the recurrent laryngeal nerve. The use of intraoperative neuromonitoring (IONM) can prevent bilateral nerve damage but in cases of accidental nerve damage primary reconstruction can improve vocal cord function. Autotransplantation of parathyroid tissue can reduce the rate of hypoparathyroidism but cannot be postulated as a routine measure. Intraoperative bleeding can usually be well controlled and greater danger for the patient emanates from early postoperative bleeding for which many techniques (clip, ligature, vessel sealing) can be employed for prevention. Lesions of the thoracic duct can be controlled by clip, ligation or stitch. Smaller lesions of the trachea and esophagus can be secured with direct suture or muscle flap plasty. In cases of larger lesions plastic reconstruction or organ replacement can be necessary.

[Morbidity and costs in complete thyroidectomies. Improvement in Value of the Process by a change in the management]

OBJECTIVES

1) To present the postoperative morbidity of complete thyroidectomies and the results of their clinical management and costs obtained after surgery. 2) To compare the results obtained for the morbidity and costs in the complete thyroidectomy Process, after the management changes introduced by the Endocrine Surgical Unit (ESU). 3) To define whether these changes improve the Value (benefit/cost ratio) of the Process.

MATERIAL AND METHODS

Prospective study of cohorts conducted on 529 complete thyroidectomies performed between 1998 and 2011. We present their clinical-pathological characteristics and we compare the clinical and management results obtained after surgery in 2 time periods: 1998-2006 without ESU (group 1, 205 patients) and 2007-2011 with ESU (group 2, 324 patients). The clinical results and the possible benefits are assessed by studying the morbimortality (recurrent lesions, hypocalcaemia [<8 mg/dl], suffocative haematomas and bleeding), and those of management, for the evaluation of the use of operating room time, the average stay and the total cost of the Process. The statistical comparison study was made using Student t test, for the comparison of means and the Chi(2) to compare percentages, accepting P<.05 as significant.

RESULTS

The global percentage of transient recurrent dysfunctions (TRD) was 6%, and for definitive recurrent paralysis (DRP) it was 1.5%. Hypocalcaemia, at 24 hours was 54.6%, at one month 7%, at six months 6.2% and that of definitive hypoparathyroidism 1.3%. There were 2.8% of suffocative haematomas and 2% adverse effects. The mean surgical time was 98 minutes, and the average stay was 3.66 days. In the comparison of results of the groups, the ESU improved the TRD index by nearly 7 points (10.2 vs. 3.4%, P=.002), that of DRP by 1.5 (2.4 vs. 0.4%; P=.3) until reaching under 1%. The figures on bleeding at 24 hours (53 vs. 44 cc; P=.002) and 48 hours (23 to 17 cc; P<.001), the rate of haematomas by another 6 points (6.3 vs. 0.6%; P<.001), and that of hypocalcaemia at 24 hours (P=.01). The average stay also improved (4.79 vs. 2.94 days; P<.001), the use of operating room time (reduced by 20 minutes/operation; P<.001), the total cost of the Process, decreasing by more than € 2,000/Process (P<.001), and produced a total savings for the hospital in the period of study of € 665,820.

CONCLUSIONS

1) The global results (post-operative morbidity) of our total thyroidectomies are within the quality standards. 2) The surgical specialisation and the changes introduced by the ESU improved the clinical results (greater benefit) and those of management, cutting down the average stay and the operating room usage time and decreasing costs. 3) The change in management increased the Value of the Process.

Low bone turnover and increase of bone mineral density in a premenopausal woman with postoperative hypoparathyroidism and thyroxine suppressive therapy

We report the case of a 36-year-old woman who developed permanent hypoparathyroidism after thyroidectomy for differentiated thyroid carcinoma. A 6-year follow-up showed an increase of 11% in absolute bone mineral density at the spine and 6% at the hip accompanied by low bone turnover despite thyroid-stimulating hormone suppressive thyroxine therapy.

Intra- and postoperative parathyroid hormone-kinetics do not advocate for autotransplantation of discolored parathyroid glands during thyroidectomy

BACKGROUND

Thyroidectomy continues to pose the risk of typical complications, including postoperative hypocalcemia and permanent hypoparathyroidism. The strategic decision on how to preserve parathyroid hormone (PTH) secretion relies on assessing the viability of the parathyroid glands (PGs). The aim of this study was to assess parathyroid discoloration as an indicator for loss of parathyroid function.

METHODS

The prospective study included 29 patients (24 women, 5 men; age 53.2 ± 13.0 years) who underwent near-total or total thyroidectomy. An intra- and postoperative PTH and calcium monitoring was performed. The intraoperative situs of the PGs was documented by a study protocol. The patients were grouped in three categories: group A, 12 patients with four visualized and normally colored PGs; group B, 13 patients with four visualized and three or four discolored PGs; group C, 4 patients who had undergone autotransplantation of two PGs.

RESULTS

Compared to group A, groups B and C showed sharper intraoperative PTH declines. PTH values recovered more quickly in group B than in group C. However, no significant differences in PTH kinetics were found in the general linear model for repeated measures (p = 0.132). However, a significantly higher incidence of protracted hypocalcemia-related symptoms for more than 14 postoperative days was found for group C (50.0%) than for groups A (0%) and B (0%; p = 0.011). None of the patients developed permanent hypoparathyroidism.

CONCLUSIONS

The function of discolored PGs is only transiently impaired and recovers within a short time after surgery. Our observations do not support autotransplantation as a generally applicable first-line intervention for discolored PGs in the absence of other criteria for autotransplantation.

[Intraoperative neuromonitoring of thyroid gland operations : Surgical standards and aspects of expert assessment]

Intraoperative neuromonitoring (IONM) was introduced into thyroid surgery approximately 10 years ago for better identification of recurrent laryngeal nerve palsy. Since then several studies have been performed for evaluation of this new technology. IONM is superior to visual nerve identification alone for prediction of postoperative local cord function. Therefore, in bilateral procedures IONM enables intraoperative decision-making concerning resection of the second side. To avoid misinterpretation of the results of IONM a standardized approach including preoperative and postoperative laryngoscopy and preresection and postresection vagus stimulation is recommended. Trouble-shooting requires systematic checking of the device including control of electrode position (needle or tube electrodes). For expert assessment purposes documentation of the standardized application of IONM is of utmost importance.

Electromyographic (EMG) neuromonitoring in otolaryngology-head and neck surgery

Intraoperative neuromonitoring (IONM) is a relatively recent advance in electromyography (EMG) applied to otolaryngology-head and neck surgery. Its purpose is to allow real-time identification and functional assessment of vulnerable nerves during surgery. The nerves most often monitored in head and neck surgery are the motor branch of the facial nerve (VII), the recurrent or inferior laryngeal nerves (X), the vagus nerve (X), and the spinal accessory nerve (XI), with other cranial lower nerves monitored less frequently. Morbidity from trauma to these nerves is significant and obvious, such as unilateral facial paresis. Although functional restorative surgery is usually considered to repair the effects of such an insult, the importance of preventing nerve injury in head and neck surgery is obvious. This article focuses on the anesthetic considerations pertinent to IONM of peripheral cranial nerves during otolaryngologic-head and neck surgery. The specific modality of IONM is EMG, both spontaneous and evoked.