Thyroidectomy: Technique

This video will demonstrate a technique of thyroidectomy applicable for children and adolescents. The patient is initially placed in a supine position with the neck extended by placing a roll beneath the shoulders and sandbags on either side of the head. A nerve monitor is used to aid in identification of the current laryngeal nerve during dissection. This nerve monitor requires a sensor placed around the endotracheal tube positioned at the level of the vocal cords for the nerve monitor to work properly. Grounding electrodes for the nerve monitor are placed in the patient's skin and secured with a derm. The patient is then placed in reverse Trendelenberg position. The neck and upper thorax are prepped, and a head towel is placed to maintain sterility on the lateral neck. Folded towels are placed. The surgeon stands on the side opposite the lobe being resected. The incision is marked 2 to 3 centimeters above the sternal notch along a skin crease using a pen. In smaller children, an equivalent incision is chosen between the thyroid cartilage and the suprasternal notch. The lateral ends of the incision are curved to follow Langer's lines and must be symmetrical. The incision should extend the same distance on each side of the midline and usually continues beyond the anterior border of the sternocleidomastoid. Shorter incisions not only provide inadequate exposure, but due to excessive retraction may be cosmetically unappealing. Number 15 blade scalpel is used to incise the skin sharply. Skin hooks are used to retract the skin during dissection to minimize tissue trauma. Electrocautery is used to divide the subcutaneous tissue and the platysma. Once the platysma is divided, the skin and the platysma are lifted upwards with double skin hooks to allow for the creation of a subplatysmal flap. Maintaining the dissection close to the platysma ensures that the cervical fascia is not included in the flap. The superior flap extends upward to the thyroid notch, and the lower flap extends downward to the sternal notch. This procedure should be blood-free as the superficial veins lie in the cervical fascia. To retract the skin flaps, a wheatlander, gelpie, or Mahona retractor may be used. After the flaps are created, the strap muscles are divided by incising between the anterior jugular veins. This opening extends from the thyroid cartilage superiorly to the suprasternal notch inferiorly. The strap muscles are then dissected to allow their retraction laterally. If there is local invasion by a thyroid neoplasm, the thyroid lobe is resected and blocked with its overlying strap muscles. Dissection close to the strap muscles minimizes bleeding. The correct plane of dissection is entered when the vessels overlying the thyroid gland become prominent. The loose areolar tissue overlying the thyroid gland is divided with an electrocautery. The strap muscles are firmly retracted laterally while the thyroid gland is drawn medially to permit further medial rotation of the thyroid gland. The middle thyroid vein is ligated with ligature or suture ligation. Further mobilization of the thyroid gland is obtained by dissecting the superior pole with a retractor in place. The upper portion of the strap muscle is drawn cephalide. Concurrently, the thyroid gland is firmly retracted downward. With the use of a kitner dissector in a right angle, the upper pole is dissected. The terminal branches of the superior thyroid artery and vein are identified and ligated with ligature or suture. Care is taken to stay directly on the gland in order to minimize the risk to the external laryngeal nerve. After division of the superior pole, the thyroid gland can be easily rotated medially, and attention is now directed towards identification of the parathyroid and recurrent laryngeal nerve. The thyroid gland is then rotated medially. The recurrent laryngeal nerve is identified in the tracheoesophageal groove. Identification of the nerve is necessary to prevent injury. A nerve monitor may aid in dissection. The parathyroid glands are then identified as small yellowish brown tissue with a single small artery entering the gland. It is important to maintain blood supply to the parathyroid during dissection. The upper parathyroid gland is usually found behind the upper third of the thyroid adjacent to the cricothyroid junction, while the inferior parathyroid gland is found near the inferior thyroid artery on the posterior surface of the thyroid, though the location may vary. If in doubt, a frozen section of rapid PTH may be used. Dissection now proceeds around the lower pole of the thyroid. The pole is mobilized by careful dissection on the gland with bipolar electrocautery. The gland is rotated medially. Nerve integrity is assured. The thyroid lobe and the isthmus are dissected off the anterior lateral wall of the trachea. While the recurrent laryngeal nerve is kept under direct vision, if a partial thyroidectomy or a lobectomy is to be performed, a ligature is used to transect the thyroid and the isthmus from the remaining lobe. If a total thyroidectomy is to be performed, the remaining lobe is removed in a similar fashion. The loose areolar tissue is divided with electrocautery, and the strap muscles are retracted laterally, while the thyroid is being retracted medially. The middle vein is taken with ligature. The superior pole vessels are then identified, dissected, and taken with ligature. The thyroid is rotated medially and bipolar electrocautery is then used to dissect directly on the thyroid gland while watching for the nerve and parathyroid glands. Dissection must proceed directly on the thyroid itself in order to avoid injury to surrounding structures. The nerve is identified with direct visualization, and its course is confirmed with a nerve monitor. The nerve lies in the tracheoesophageal groove as it passes posterior to the inferior pole of the thyroid. The nerve travels obliquely closer to the gland and crosses the inferior thyroid artery and ascends into the larynx. The parathyroid gland is identified and care is taken to ensure it and its blood supply are intact. If a parathyroid gland is taken during the dissection or blood supply to it is compromised, it may be auto-transplanted into the sternocleidomastoid or the non-dominant forearm. The gland should be placed in saline in an ice bath until autotransplantation is performed. The sternocleidomastoid muscle is dissected. A suitable muscle pocket is then dissected. The parathyroid is minced with tenotomy scissors and a small amount of saline and drawn into a syringe. This is then injected into the sternocleidomastoid muscle, taking care not to create a hematoma. The muscular pocket is then closed with a prolene suture. The inferior pole vessels are then taken and the remaining thyroid gland is dissected off the trachea using bipolar electrocauteery. The thyroid is sent to pathology for further evaluation. The operative area is inspected and hemostasis is assured. The deep cervical fascia in the midline is sutured with 30 absorbable suture. For a good cosmetic result, the platysma is carefully approximated with 30 absorbable suture. The skin is closed with a running 40 non-absorbable monofilament that is then removed the next day. An absorbable monofilament may also be used. Steri-strips are placed on the wound and on the edges of the removable, non-absorbable suture. The patient is extubated and taken to recovery.