Thyroidectomy
Introduction:-
Thyroidectomy is a surgical procedure that involves removal of all or some part of the thyroid gland.
Anatomy:-
Location
The thyroid gland is situated in the neck, below the larynx (voice box), and wraps around the trachea (windpipe).
Structure
The thyroid gland consists of:
1. Two lobes (right and left)
2. Isthmus (connects the two lobes)
3. Follicles (small sacs containing thyroid hormone-producing cells)
Components:-
1. Thyroid follicular cells (produce thyroid hormones)
2. Parafollicular cells (produce calcitonin)
3. Thyroid stimulating hormone (TSH) receptors
Blood Supply:-
1. Superior thyroid artery (branches from external carotid artery)
2. Inferior thyroid artery (branches from thyrocervical trunk)
3. Thyroid veins (drain into internal jugular vein)
Nerve Supply:-
1. Superior laryngeal nerve (branches from vagus nerve)
2. Recurrent laryngeal nerve (branches from vagus nerve)
Indication :-
Toxic multinodular goiter ,does not respond well to antithyroid drug or radio- iodine
Toxic solitary nodule
Malignant goiter
Large goiter that doesn't respond to drugs
Cosmesis
Exophthalmus
Contraindications:-
Recurrent thyrotoxicosis
Thyrotoxicosis without a palpable thyroid
Drug goiter
Children
Thyrocardia
Types of THYROIDECTOMY :-
It has various type
Hemithyroidectomy :-
Hemithyroidectomy is a surgical procedure that involves the removal of half of the thyroid gland, typically one lobe, usually performed to treat thyroid nodules, tumors, hyperthyroidism, or cancer confined to one lobe.
Subtotal thyroidectomy :-
Subtotal thyroidectomy is a surgical procedure that involves the removal of most of the thyroid gland, leaving a small portion (usually 1-2 grams) of thyroid tissue behind, to preserve thyroid function and reduce the risk of hypothyroidism.
Total thyroidectomy :-
Total thyroidectomy is a surgical procedure that involves the complete removal of the entire thyroid gland, typically performed to treat thyroid cancer, severe hyperthyroidism, or large goiters that cause symptoms or obstruct the airway.
Isthmusectomy :-
Isthmusectomy is a surgical procedure that involves the removal of the isthmus, the narrow band of tissue connecting the two lobes of the thyroid gland, often performed to:
1. Treat thyroid nodules or tumors confined to the isthmus
2. Relieve compression of adjacent structures (e.g., trachea, esophagus)
3. Access or remove cancerous tissue in the isthmus.
Diagnostic:-
TFT — T3,T4 and TSH
Serum calcium levels are obtained because hyperparathyroidism may coexist.
High resolution USS
FNAC
Pre operative management
Thyrotoxic patient are rendered euthyroid;
1)Carbimazole 10-15 mg 8 hourly, when patient become euthyroid(in about 4 weeks) they are maintained on 5-10mg
Propranolol 80mg 6hourly 4-7 days before operation. Symptoms and signs are usually
controlled within 24 hours. Continued 8-10 days post op
Lugol's iodine; 2 weeks preoperatively to reduce the vascularity of the gland
2) Informed consent is obtained
Procedure :-
POSITION:-
• patient is placed in a supine position initially with the neck extended by placing a ring beneath the head and a sandbag roll beneath the shoulder.
• The table is tilted 20-30 degrees "head up" to aid in emptying the neck veins.
• The skin is prepped from the chin to the upper thorax
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anesthesia:- Anaesthesia is general with cuffed
endotracheal tube
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Clean the surgical site using Betadine,sides of neck , chest
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• Drapes are applied; head scarf, sides of the neck, chest-abd, large covering the legs. The are secured with clips
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INCISION:-
→Site of incision is indented with suture
→A transverse skin crease incision is placed 2-3 cm above the sternal notch about 8 cm long extending to the lateral borders of sternocleidomastoid.
→ The scalpel (with size 15 blade) is slanted to divide the skin and platysma at different level to give a neater scar
→ Hemostasis is controlled with electrocautary or prior infiltration with lidocaine and adrenaline
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→ Elevate the flap of skin with the platysma (the assistant lifts the skin and the platysma upward with double skin hooks to allow for the creation of a subplatysmal flap).
• Superiorly to the thyroid cartilage
• Inferiorly to the suprasternal notch
• Place Joll's retractor to retract the skin flaps
This procedure should be blood free, because the superficial veins lie beneath the cervical fascia.
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• Divide the deep cervical fascia longitudinally in the midline, between the anterior jugular veins.
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• At the lower part there is usually a transverse cervical vein that needs to be clamped, divided, and ligated with 3-0 silk sutures
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• The strap muscles (sternohyoid, and deeper sternothyroid) are carefully separated to allow their retraction laterally.
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• Assess goiter;
→The loose areolar tissue (capsule) overlying the thyroid glands is divided with electrocautery.
→After the anterior surface of the thyroid has been thoroughly exposed, the entire gland is carefully explored and palpated.
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• The strap muscles are firmly retracted with a small loop retractor while the thyroid gland is drawn medially
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Ligate and divide in continuity
→Middle thyroid vein
→Superior thyroid vessels close to the gland(to avoid injury to the external laryngeal nerve) between two proximal and one distal ligature.
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• The recurrent laryngeal nerve and the parathyroids are identified and preserved then the terminal branches of the inferior thyroid artery are ligated and divided close to the capsule. Or the inferior thyroid artery is identified far away from the gland ligated in continuity to avoid injury to the recurrent laryngeal nerve.
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• The thyroid is then mobilized and removed;
→ Divide isthmus and place hemostats around margin of resection (run with interlocking 3-0 absorbable suture) leaving about 4g of thyroid from each lobe for subtotal
→ If a total thyroidectomy is being performed, the remaining lobe is removed in a similar fashion, with division of the middle thyroid vein, identification of the recurrent laryngeal nerve and parathyroid glands, and ligation and division of the superior pole and branches of the inferior thyroid vessels.
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CLOSURE:-
• Absolute haemostasis
• Suction drain to thyroid bed (beneath the strap muscles)
• Close loosely in layers with absorbable sutures
• Close the skin with sutures or clips
• Check vocal cords on extubation by direct laryngoscopy
POST OPERATIVE MGT:-
• Half-hourly observation until conscious
• At the bedside
→ Michel clip remover in case of respiratory distress due to hematoma
→10 ml of 10% calcium gluconate in case of acute hypocalcemia
• Keep semi-recumbent
• Review indirect laryngoscopy(especially if there is cord impairment on extubation)
• Serum calcium regularly in the postoperative period
• Thyroid func
tion tests at 6 weeks postoperatively
• Remove
→ Drain when dry, 24-48 hours postoperatively
→Sutures/clips, 2-3 days postoperatively
Cristal clear
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