Archive \ Volume.15 2024 Issue 2

Complications after Surgery on the Thyroid Gland: A Review

The aesthetic results of thyroid surgery are of paramount importance for most women and young people who undergo it. Achieving favorable aesthetic results is especially important during thyroidectomy surgery. An incision made in a prominent anatomical area on the neck should be as delicate and non-traumatic as possible. However, traditional thyroidectomy is associated with a greater risk of scarring than less popular endoscopic methods; Scars can not only be noticeable but also cause symptoms such as a foreign body sensation and difficulty swallowing. Scar tissue can spread beyond the surface of the skin into the muscles up to the thyroid cartilage (Kim) [7].

As a result of studying the risk factors for hypertrophic scar formation after thyroidectomy, it was found that protruding sternocleidomastoid muscles and a small distance between the incision and the jugular notch are associated with a higher frequency of hypertrophic scar formation [8, 9]. Insufficient attention is paid to hypertrophic scars in the scientific literature.

Since nerve fibers and blood vessels that supply muscle cells with blood can be damaged or altered, postoperative dysphagia is often associated with surgical interventions for paratracheal tumors or hyperthyroidism [10, 11]. During surgery, the most common complications of thyroidectomy are bleeding and hematomas. This is because the thyroid gland has an abundant blood supply, which increases the risk of bleeding [12]. The effects of bleeding are still unknown in clinical studies. In most cases, blood loss is caused by insufficient compression of small vessels or insufficient coagulation, spikes in blood pressure, or damage to thyroid tissue. Swelling of the neck does not always indicate severe blood loss; rather, it may indicate superficial blood loss in or under the muscle layers. Over time, hematomas can become even more dangerous as their bleeding increases; unfortunately, they often do not cause swelling of the neck, which makes them difficult to detect. Pressure can rapidly increase in a limited area of the neck, which leads to respiratory failure or hypoxia and congestion in the larynx, followed by venous-lymphatic blockage in the endotrachea. This increases breathing difficulties and the risk of hypoxia. Thus, a deep neck hematoma can be much more dangerous than one located closer to the surface, since most of them occur within 24 hours after surgery [13].

In the traditional practice of hemostasis, large vessels are ligated, and smaller vessels undergo bipolar coagulation for hemostasis [14]. This method is quite safe, and effective, and the risk of damage to nerves and parathyroid glands is minimized, unlike monopolar surgery, which should be avoided due to elevated temperatures resulting from concomitant damage, which is caused by an increased risk of bleeding [15]. It has been suggested that the use of ultrasound dissection can reduce both intraoperative and postoperative blood loss, as well as reduce thermal damage to critical structures.

Some authors, for example, recommend loosely suturing muscles with tourniquets to prevent deep hematomas. Most patients who have undergone thyroid surgery are recommended to undergo 24-hour postoperative follow-up. When stridors and shortness of breath appear in combination with the development of bleeding, an urgent reaction is necessary. The reopening of the surgical wound should be carried out as soon as possible to drain as much blood as possible, and then return the patient to the operating room for a repeat operation.

Damage to the recurrent nerve caused by laryngectomy has been reported for a long time. This branch of the vagus nerve provides all the muscles of the larynx, and the cricoid gland, except those that supply the cricoid gland. These nerves run unevenly. The left nerve is located under the segment of the aorta, and its branch runs along the subclavian vein before ending at the neck. Passing through the tracheoesophageal sulcus, the nerves connected to the thyroid gland can enter at levels close to where the cricoid gland is located in the throat. Most often, damage to the recurrent pharynx occurs near this nerve entrance to the larynx. Unilateral paresthesia causes flabbiness of one vocal fold, which leads to dysphonia, which progresses to complete paralysis of the vocal cords [16]. The consequences of repeated damage to the larynx (RLN) can become more serious over time. With unilateral damage to the laryngeal nerve, the affected vocal cords can atrophy and reduce voice quality, while bilateral damage causes closure of the glottis, which leads to biphasic stridor, respiratory distress, and possible aphonia; urgent interventions such as tracheostomy or intubation may be required as immediate treatment [17]. RLN dysfunction may occur during extubation after total thyroidectomy. However, damage does not always lead to paralysis - in the case of partial damage, symptoms can still manifest unilaterally or bilaterally, although they can usually be milder due to partial damage rather than incomplete paralysis. Such injuries can occur for a variety of reasons, including insufficient visualization during surgery, anatomical changes and bleeding during or after surgery, as well as the formation of edema. Monitoring damage to the recurrent laryngeal nerve (RLN) during surgery, even in complex cases involving cancer, large goiter, or repeated operations, is of great importance. According to studies, the frequency of irreversible nerve damage ranged from 0.5 - 5.0%, while temporary damage occurred in 1-30% of cases [18].

CONCLUSION

Modern advances in surgical techniques, hemostatic measures, and intraoperative monitoring have dramatically enhanced both safety and efficacy during thyroid surgery in recent years. Key developments include intraoperative monitoring of the recurrent laryngeal nerve and techniques for identifying and conserving parathyroid glands. Preventing complications during thyroid surgery requires an in-depth knowledge of cervical anatomy and histology. Surgeons require in-depth knowledge of the intricate structures surrounding the thyroid gland, including its nerve supply (recurrent laryngeal nerve), parathyroid glands (parathyroid glands), and their respective blood supplies. Visualization techniques play a pivotal role in accurately identifying and protecting vital structures, like nerves and parathyroid glands. Surgeons take great care during surgery to avoid inadvertent damage or removal of these essential elements. Intraoperative monitoring techniques enable real-time evaluation of nerve function and early identification of complications during surgery. Furthermore, methods like meticulous dissection and careful hemostasis help mitigate bleeding risk while simultaneously decreasing tissue trauma during procedures. Healthcare providers strive to optimize patient safety and outcomes during thyroid surgery by adhering to best practices and employing advanced surgical tools. Furthermore, patients should receive adequate consultation regarding potential complications before surgery, so that they are fully aware of all possibilities before going under anesthesia.

ACKNOWLEDGMENTS: All the authors were involved in the conceptualization, methodology, formal analysis, writing, and editing of the manuscript.

CONFLICT OF INTEREST: None

FINANCIAL SUPPORT: None

ETHICS STATEMENT: None