Endocrine Surgery | The Thyroid Gland

The Thyroid Gland

The thyroid is a butterfly-shaped gland located in the neck, surrounded by major vessels, the trachea (windpipe), and the larynx (voice box). The hormones the gland produces (most importantly T3 and T4) regulate metabolism. A third hormone produced by the thyroid, Calcitonin, regulates calcium in the body.

Because the thyroid regulates metabolism, it is also involved in the regulation of body weight and temperature, heart rate, alertness, growth, bowel activity, and menstrual cycles in women. Overactivity of the thyroid results in increased metabolism with weight loss despite an increased appetite, an increased heart rate, heat intolerance, shaky hands, and in some cases, an eye bulge. Symptoms often vary depending on the severity and the person.

An enlarged thyroid (Goitre) is usually visible in the mid-lower part of the neck. In some cases, the thyroid can grow down into the upper part of the chest cavity, where it won’t be visible to the outside.

Anatomy

The thyroid is situated at the front of the neck, right under the ‘Adam’s Apple”. It lies on either side of the trachea (windpipe), and the oesophagus (food pipe). It has an extensive blood supply.

The major blood vessels of the neck pass on either side of the thyroid. Recurrent laryngeal nerves controlling the voice box pass behind the thyroid.

Four small glands, called the Parathyroid Glands are situated near the thyroid gland. These glands produce a hormone that controls calcium levels in the blood.

Surgery

In some cases, your doctor may recommend partial or total surgical removal of the thyroid gland. Indications for this procedure are usually as follows:

Proven malignancy (cancer) of the thyroid.
Suspicion of malignancy.
Over-active or toxic thyroid.
Enlarging nodule in the thyroid.
Pressure symptoms
Cosmetic reasons

The operation is done under general anaesthesia via an incision in the front of the neck. The length of the incision depends on the size of the thyroid to be removed. To perform the surgery, important structures such as muscles and major blood vessels are moved aside, whereas smaller blood vessels directly connected to the thyroid are ligated (tied off). The thyroid is then lifted off and separated from the trachea, before being completely removed.

During the operation, every effort is made to preserve the two very important laryngeal nerves (which are important for speech), and the parathyroid glands (which are important for calcium control).

A final check is done before the closure is achieved using an absorbable suture. This means the stitches do not need removal. The decision on whether or not to leave a drain in the wound is made during the operation. If a drain is left in the wound, it is usually removed within the first 48 hours post-op.

Post-Operative

After the operation, you will be nursed in a semi-upright position and will be allowed oral intake (food and drink) a few hours after the procedure. You can shower the day after surgery, and will usually be sent home 1-3 days later. It is advisable to take 10-14 days off work for recovery.

Medications: After a total thyroidectomy (where the entire thyroid is removed), medications required are usually a temporary calcium supplement, and permanent thyroid hormone replacement (Thyroxine).

Thyroxine tablets provide a complete replacement for the thyroid gland. Patients on the proper dose of Thyroxine have a normal life expectancy and normal function.

Blood tests are required regularly after a total thyroidectomy to check the dosage of Thyroxine needed. The frequency of these tests gradually reduces down to yearly.

Complications

Possible Complications

Complications, while rare, can happen with any surgical procedure.

General Complications

General Complications are those that can happen with any instance of general anaesthesia and surgery. These include cardiac and respiratory complications, such as a heart attack or chest infection.

Deep Vein Thrombosis (DVT) is a rare complication where a blood clot can form (often in the leg), and be dislodged, travelling up the bloodstream to the heart or lungs.

Delayed Complications

Contact Mr Haddawi or your GP, or visit the emergency department if you have any of the following problems after being discharged from the hospital:

Tingling sensation around your mouth or your fingers (take 2 calcium tablets immediately).
Fever, redness, or swelling around the wound.
Painful and tender calf muscles.
Shortness of breath or an excessive cough.

Specific Complications

These are potential complications specific to a partial or total thyroidectomy.

They can include:

Bleeding - this is uncommon and usually not serious. Occasionally, persistent bleeding will require a second trip to the theatre for a washout, especially if this is causing difficulty breathing.
Injury to the recurrent laryngeal nerves - if one nerve is injured, you will notice thick hoarseness in your voice. This complication is very rare (with an incidence of roughly 1%) and is usually temporary. Injury to both nerves is even rarer (1 in 500), but may cause the loss of the ability to speak, and in severe cases, require a tracheostomy (breathing tube in the neck). The risk of nerve injury increases in cases involving malignancy (cancer) of the thyroid, or a very large gland.
Injury to the external branch of the superior laryngeal nerve - is often due to the variability of the nerve position about the main vessels of the upper thyroid. Damage to this nerve manifests itself as the inability to produce high-pitched sounds (i.e. when screaming/singing).
Parathyroid gland damage - the temporary dysfunction of these glands is common, hence why calcium supplements are taken temporarily post-op. Complete damage to all four glands is rare, occurring in about 2% of all cases. The treatment for this is long-term calcium supplements.

There is no direct relationship between the size of the thyroid and its activity; a very small gland can be over-active, whereas a large gland can have normal or even low levels of activity.

Goitres can be asymptomatic or can cause a pressure effect on the trachea (windpipe) and oesophagus (food pipe), or occasionally press on the nerves behind the thyroid.