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 Table of Contents  
ORIGINAL ARTICLE
Year : 2018  |  Volume : 6  |  Issue : 1  |  Page : 29-34

Pits and pearls in the management of giant goiters


Department of Otolaryngology Head and Neck Surgery, Postgraduate Institute of Medical Education and Research, Chandigarh, India

Date of Web Publication29-Jun-2018

Correspondence Address:
Prof. Naresh K Panda
Department of Otolaryngology, Postgraduate Institute of Medical Education and Research, Chandigarh
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jhnps.jhnps_15_18

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  Abstract 


Objective: Giant goiters invariably have been neglected by the patients allowing them to grow to huge sizes. Usually, these are slow growing and are not troublesome, and hence, the patients ignore them. The treatment of such goiters is surgery. However, when these become >10 cm, they pose challenges to the patient, the anesthetist, and foremost the surgeon. Materials and Methods: We present here a single-institutional experience of managing 13 monster goiters. Harmonic scalpel and bipolar cautery were used intraoperatively. The surgical loupes were used in all cases for identification of the nerves. Their clinical presentation, salient symptoms and our experience, and key factors affecting successful outcomes were analyzed. Results: Ten patients had benign lesion and three harbored malignancy. All patients were made euthyroid before surgery except one in whom the indication for surgery was thyrotoxicosis. All patients underwent awake fiber-optic intubation. Four patients underwent total thyroidectomy, two underwent hemithyroidectomy, and remaining underwent subtotal thyroidectomy. One patient required sternotomy for retrosternal extension of the goiter. Harmonic scalpel and bipolar cautery were used intraoperatively. Surgical loupes were used in all cases for identification of the nerve. In all cases, recurrent laryngeal nerve was identified. Tracheomalacia was noted in two patients, and only one of them had to be tracheostomized postoperatively. Conclusion: Anatomy was found to be distorted in all our cases. Identifying the nerve was difficult due to distorted anatomy. Transient hypocalcemia was a consistent feature in spite of identifying the parathyroids and preserving its blood supply. Cases with tracheomalacia and bilateral vocal cord palsy can pose challenge for extubation, and tracheostomy needs to be considered in them.

Keywords: Giant goiter, retrosternal goiter, tracheomalacia


How to cite this article:
Panda NK, Subash A, Singh A, Verma RK. Pits and pearls in the management of giant goiters. J Head Neck Physicians Surg 2018;6:29-34

How to cite this URL:
Panda NK, Subash A, Singh A, Verma RK. Pits and pearls in the management of giant goiters. J Head Neck Physicians Surg [serial online] 2018 [cited 2018 Dec 14];6:29-34. Available from: http://www.jhnps.org/text.asp?2018/6/1/29/235622




  Introduction Top


Deficiency of iodine is the leading cause of goiters. Some patients still present with giant goiters. These patients have allowed their thyroid gland to assume enormous size over many years. They present to the surgeons with either rapid increase in size or pain.

Surgical management of these giant goiters is no different from routine thyroid goiters. However, there are some unique issues that must be addressed. These giant goiters distort the normal anatomy and hence increase the risk of nerve injury and hemorrhage. Rapid increase in size may suggest an underlying malignancy. These large tumors can have intrathoracic extension. Retrosternal goiter has been classified as primary or secondary, the majority being secondary.[1] The downward extension of the gland along the planes of the cervical and mediastinal fascia results in retrosternal extension. Mediastinal extension of the gland is usually apparent on imaging.

Airway complications are quite common after resection of large goiters. Three basic predictors of airway complications have been identified and include old age, size of the tumor, and preoperative evidence of tracheal compression on imaging. Shen et al. reported the predictors of airway complications and the incision of choice in relation to the size of the tumor.[2]

Large goiter poses challenge to both the surgeon and the anesthesiologist. We present here our experience of managing monster goiters at a tertiary care hospital.


  Materials and Methods Top


We present a series of 13 cases of giant goiters treated at our institute from 2011 to 2016 [Table 1]. All the patients were operated by the senior surgeon NKP who was ably assisted by AS and AS. Ten of the patients had a benign disease while three were harboring malignant lesions on fine-needle aspiration cytology [Figure 1]. All these patients were treated surgically. They were operated in the conventional thyroid position with patient lying supine and head extended with elevated shoulders. The elevated shoulder position facilitated to make the goiter more prominent in the neck. It was ensured that all patients were euthyroid before surgery. High blood pressure and cardiac arrhythmias were appropriately controlled before posting these patients for surgery. All patients underwent fiber-optic bronchoscope-guided awake intubation considering the risk of difficult intubation due to probable compression of the trachea. The ethical approval for the same study was obtained from the Ethics Committee of PGI Chandigarh.
Table 1: The clinical and surgical details of all the patients

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Figure 1: (a-d) various patients with large goiters

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Keeping in line with our departmental protocol, a single dose of prophylactic intravenous antibiotic was administered 30 min before making the skin incision and repeated if the duration of surgery was more than 4 h. Laryngeal examination was routinely done both preoperatively and after extubation for assessment of vocal cords mobility.

The cases with substernal extension radiologically were considered for sternotomy. In most cases with retrosternal extension, the lower end could be freed using blunt finger dissection through the transcervical incision. In our series, one patient required sternotomy to gain access to the retrosternal extension [Figure 2]. A transverse cervical incision extending from the anterior border of one sternocleidomastoid muscle to the other was made and two-finger breadth above the clavicular head. The subplatysmal flap was elevated superiorly till the hyoid bone for adequate exposure. Inferiorly flaps were raised till clavicular heads to achieve good exposure. Strap muscles were found to be thinned out in most of the cases and were divided to gain access to the enlarged lobe. Superior thyroid pedicle was identified and ligated first; this helped us to mobilize the lobe. Joll's triangle, also known as sternothyrolaryngeal triangle, was distorted and was sans helpful intraoperatively to identify external branch of the superior laryngeal nerve. The middle thyroid vein was ligated next. Dissection was carried out meticulously around the lower pole to identify the inferior thyroid pedicle and its branches to the parathyroid gland. Beahr's triangle bounded by the trachea, carotid artery, and nerve itself, which is used to identify the recurrent laryngeal nerve (RLN), was also distorted, and the use of surgical loupes with ×2.5 magnification aided in proper identification of the nerve.[3] We did not use any nerve monitor for nerve identification. Once identified, the nerve was traced proximally till it entered the cricothyroid joint. The nerve in all cases was abnormally stretched and had a distorted anatomical course. Small blood vessels lying medial to RLN often were a source of bleeding during dissection. This area has aptly been named “the triangle of concern.” The triangle is bounded by RLN, trachea, and root of the neck.[4] Bleeders from these vessels were invariably present in all cases, and we had had to be extra cautious while securing hemostasis using bipolar cautery. Diffuse ooze from this area was managed by placing strips of methylcellulose (SURGICEL by Ethicon Surgical). In cases where excessive manipulation of the nerve was done, a patient was given intraoperative dexamethasone.
Figure 2: Sternotomy to address retrosternal extension

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All attempts were made to preserve the blood supply to the parathyroid glands. This was again facilitated by the use of magnifying loupe. The parathyroid glands were preserved in all the cases. In this study, majority of our patients undergoing total/subtotal thyroidectomy developed postoperative transient hypocalcemia. However, none of the patients required calcium or Vitamin D3 supplementation on the long run.

After securing hemostasis, the neck wound was closed over a 16 French gauge suction drain. The anesthetist assessed the status of vocal cord during extubation with the help of videolaryngoscope.


  Results Top


This observational study was carried out from 2011 to 2016 at our institute. A total of 13 patients with giant/monster goiter were treated surgically during this period by the authors. The mean age of patients in this observational study was 45 years with a range of 22–62 ± 15 years. The eldest was 63 years old and the youngest 20 years old. There were eight female and five male patients (sex ratio 1.6:1).

Ten patients had benign lesion and three-harbored malignancy diagnosed on fine-needle aspiration cytology. All patients were euthyroid before surgery except one in whom the indication for surgery was thyrotoxicosis not responding to medical management. Six patients underwent total thyroidectomy, three underwent hemithyroidectomy, and remaining four patients underwent subtotal thyroidectomy. One patient required sternotomy for retrosternal extension of the goiter. Harmonic scalpel and bipolar cautery were used intraoperatively. Surgical loupe was used in all cases for aid in identification of RLN.

In all cases, RLN was identified [Figure 3]. One patient had preoperative vocal cord palsy. Two patients developed transient vocal cord paresis that recovered completely in the postoperative period. Two patients developed permanent vocal cord palsy. In one of the two patients, the nerve on the left side had to be sacrificed as the lesion was malignant and was adherent to the nerve. However, the right RLN was normal. The other had bilateral RLN palsy after surgery and had to be tracheostomized. In all cases, RLN had a distorted anatomical course and had been abnormally stretched due to the huge size of the tumor. None of the cases had RLN running superficial to the inferior thyroid artery or running transversely. Tracheomalacia was noted in two patients, and only one of them had to be tracheostomized postoperatively.
Figure 3: (a-d) Recurrent laryngeal nerve identified intraoperatively

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Transient hypocalcemia was noted in all patients undergoing total thyroidectomy. None of the patients required long-term calcium and Vitamin D3 supplementation. Injury to internal jugular vein (IJV) occurred in one case and was repaired intraoperatively using 6–0 prolene.


  Discussion Top


Large size of tumor makes it mandatory to have an excellent anatomical knowledge to avoid complications. Deliberate identification and carefully tracing the path of RLN have been reported to minimize the risk of injury to the nerve.[5],[6] The anatomy of RLN gets distorted due to abnormally large size of the gland. Methods that prevent RLN palsies are of great interest. One way to ensure the integrity and function of RLN is to safely identify RLN before completing thyroidectomy. However, exposure itself might increase the rate of RLN palsy because of mechanical alteration or impairment of the nutrition by the surrounding tissue.[7] The mechanism of injury to the nerve includes complete or partial transection, traction, or handling of the nerve, contusion, crush, burn, clamping, misplaced ligature, and compromised blood supply.[8]

The incidence of RLN palsy in thyroid surgery varies from 5% to 11%. Bilateral RLN palsy is a rare life-threatening complication following surgery and requires emergency management. The reported incidence is 0.1%.[9] In our series, only one patient who had malignant disease had bilateral RLN palsy and had to be tracheostomized postoperatively. The other patient who required tracheostomy probably had tracheomalacia.

Lahey in 1900 emphasized on the need for identification and preservation of the recurrent nerves.[10] He encouraged the use of surgical loupes while performing thyroid surgeries. The microsurgical technique allows to remarkably reducing the complications of thyroid surgery.[11] In this study also, the use of magnifying loupe for nerve identification played a key role in reducing nerve injuries.

The most common site of injury to RLN is close to the tubercle of Zuckerkandl and fascial layers.[12],[13] Utmost care should be taken while ligating and dividing structures, in particular, the arterial branches located behind the nerve, as securing hemostasis after an injury here carries a higher rise of damage to the nerve. In this study, bleeding was invariably encountered from these vessels due to the distorted anatomy that further risked damage to the nerve.

The permanent injury to RLN manifests as irreversible dysfunction of phonation with irreversible respiratory difficulties. Airway complications due to injury of the recurrent nerve are witnessed immediately after the patient is extubated. Depending on the extent of injury, this can cause unilateral or bilateral collapse of the vocal cords. Airway compromise in large goiters could occur due to stretching of RLN on both sides or due to tracheomalacia. It is difficult to predict the presence of tracheomalacia preoperatively. However, the probability of an airway difficulty should always be anticipated in all cases at recovery from anesthesia. In large goiters with preexisting trachea deviation, the use of glucocorticoids such as methylprednisolone and dexamethasone before extubation has shown to be beneficial in minimizing airway complications.[6]

Hypocalcemia is defined as deficiency of calcium in bloodstream (normal = 8.5–10.5 mg/dl).[14],[15] It can be temporary or permanent. Symptoms often manifest about 24–48 h after surgery, and there is no direct correlation between their timing and the severity of hypocalcemia.[16] In patients undergoing thyroidectomy, temporary hypocalcemia is seen in 1.6%–50%, and only about 1.5%–4% end up with permanent hypocalcemia.[17],[18] Postoperative hypocalcemia requires monitoring of calcium levels and its supplementation accordingly. This leads to prolongation of hospital stay and thereby increasing the health-care expense and bed occupancy. Trauma to parathyroid gland, its vasculature, or incidental removal of the parathyroid gland with the specimen leads to the development of postoperative hypocalcemia. Risk of postoperative hypocalcemia was higher in thyroidectomies performed for malignancy and in patients who underwent neck dissection.[19] In studies performed on parathyroid gland damage and incidental parathyroidectomy, authors have reported correlations between onset and longevity of hypocalcemic symptoms and the number of extracted and damaged parathyroid glands.[20],[21] In patients with large goiters, complex vascularity predisposes to the development of hypocalcemia. Unless the surgeon has ample experience with parathyroid glands and its vascular supply, routine exploration of all four parathyroid glands is not recommended.[22],[23],[24] In up to 83% of cases, parathyroid glands with impaired blood supply or when autotransplanted with intact capsules retained their biochemical activity.[25] Coimbra et al. in their study found that the extent of the surgical procedure was directly related to the incidence of transient and permanent hypoparathyroidism. Transient hypocalcemia is more frequent in less extensive surgeries such as hemithyroidectomy. Vascular manipulation compromises parathyroid function until blood flow is re-established through collateral vessels.[26] Transient hypocalcemia was treated with calcium supplementation 500 mg qid and 1.25 deoxy cholecalciferol (Vitamin D3). We invariably followed the principle of following the branches from the inferior thyroid artery to parathyroid. Sometimes, these branches could arise from superior thyroid artery as tiny twigs.

In this study, harmonic scalpel and bipolar coagulation forceps were used in all cases. The use of harmonic scalpels and bipolar coagulation forceps reduces the operative time along with postoperative blood loss. These equipment also have a bearing on postoperative voice as these are known to decrease the chances of nerve injury.[27],[28] From animal studies, it was concluded that harmonic scalpel could be used around RLN with caution. The scalpel tip should be at least 2 mm away from the nerve, and the duration of exposure should be <3 s with a power level of 3.[29]

Weak tracheal walls characterize tracheomalacia. Normal airway dilates during inspiration and narrows during expiration owing to variations in intrathoracic pressure. In patients with tracheomalacia, expiratory narrowing is exaggerated. The condition can be congenital or acquired, acquired being more common. Common causes include prolonged intubation, tracheostomy, smoking, and external pressure on the trachea. A common cause for compression and pressure over the trachea is long-standing goiters. The pathogenesis of tracheomalacia is not completely understood. Autopsy data suggest that atrophy of longitudinal elastic fibers could be the possible cause.[30] Tracheomalacia results in a dynamic airway collapse. Diagnosis is easily missed with standard imaging such as roentgenogram, and pulmonary function test has a poor sensitivity for its diagnosis. Current therapies for tracheomalacia include tracheostomy tube placement, surgical procedures to relieve compression from tumors, and intraluminal airway stents.[31] In our experience, only one patient had severe tracheomalacia that required tracheostomy postoperatively. Tracheal pliability improved after 3 months, and the patient was decannulated eventually.

Due to the huge size of these tumors and their pressure effects, IJV is usually compressed. It appears thinned out intraoperatively and prone to injury. The distorted anatomy in the area makes it even more challenging. The surgeon has to be careful while dissecting in the vicinity of IJV as injury here can result in profuse bleeding and risk of life-threatening air embolism.


  Conclusion Top


Successful outcomes in the management of monster thyroid require dedication and an extensive experience in management of goiters and thyroid malignancy. A thorough anatomical knowledge helps the surgeon to identify key structures even with the distorted anatomy. Magnifying surgical loupes in our experience were found to be useful. The use of bipolar cautery and harmonic scalpel decreases operative time and reduces risk of injury to vital structures. Tracheomalacia should be anticipated in all patients with long-standing disease, and a preoperative consent of tracheostomy should be taken. Transient hypocalcemia is a common feature following surgery, and calcium monitoring in the postoperative period is mandatory.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given her consent for her images and other clinical information to be reported in the journal. The patient understands that name and initial will not be published, and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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Serpell JW. New operative surgical concept of two fascial layers enveloping the recurrent laryngeal nerve. Ann Surg Oncol 2010;17:1628-36.  Back to cited text no. 13
    
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Sousa Ade A, Salles JM, Soares JM, Moraes GM, Carvalho JR, Savassi-Rocha PR, et al. Predictors factors for post-thyroidectomy hypocalcaemia. Rev Col Bras Cir 2012;39:476-82.  Back to cited text no. 14
    
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31.
Huang L, Wang L, He J, Zhao J, Zhong D, Yang G, et al. Tracheal suspension by using 3-dimensional printed personalized scaffold in a patient with tracheomalacia. J Thorac Dis 2016;8:3323-8.  Back to cited text no. 31
    


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