What are the complications of Thyroid Surgery?

It cannot be emphasied too strongly that in expert hands that complication are rare.

Bleeding

Sudden massive bleeding into the neck is unusual. It occurs in our hands in one in seven hundred and fifty patients (0.14%) and it can be life threatening. It occurs in the first 24 hours of surgery. Immediate removal of the neck sutures by the nurse or house doctor and return to the operating theatre to arrest the bleeding is mandatory and lifesaving.The risk of return to the operating room is still high in some institutes. A report from the University Department of Clinical & Surgical Sciences,University of Edinburgh, UK in 2008 reported a return to the operating theatre for bleeding in thyrotoxic patients of 3.06% with an overall complication rate of 13%. In 2009 a Danish group reported rebleeds in 32 cases in a total of 1201 operations (2.7%). In this report all grades of surgeons performed the thyroidectomies most likely the reason for the very high bleed rate. A recent study in the Annals of the Royal College of Surgeons (Foreman et al Ann R Coll Surg Engl 2009;91;214-216) showed that the harmonic scapel (Ethicon UK) is no less safe than traditional methods such as "clip, cut and ligate"or the use of small metallic clips in achieving haemostasis. In 2007 a young female thyrotoxic patient died in a major London teaching hospital after a thyroidectomy from bleeding. The use of the harmonic scapel (Ethicon UK) as the only means of haemostasis must in the light of Foreman's findings be considered as coincidental. The Westminster Coronor was highly critical of the patients care. The main lesson for patients from this tragic case is that one must be managed on a ward that is used to dealing with thyroidectomies. If they are not we suggest that the patient discharges themself and comes back another day when a specialist bed is available.

Slow bleeding into the neck may produce a clot of blood under the cut in the neck (haematoma). This complication occurs in less than 1% of patients and often resolves spontaneously, but may need drainage of the clot. This simple procedure can be done in outpatients with no need for anaesthetic. Rarely the clot gets infected and needs to be drained in a similar way as for a simple haematoma. The cosmetic result is usually not affected by this complication.

A photograph of a massive bleed post surgery - click to enlarge

Click to see an animation of a tension haematoma developing

Breathing Difficulties

There are two main causes of breathing problems after thyroidectomy. First, a huge clot of blood may block the windpipe necessitating urgent surgery. This has already been discussed.Second, if both recurrent laryngeal nerves have been damaged, an urgent tracheostomy (hole in the windpipe) would need to be performed. This complication is extremely rare.

Thyroid Storm

Before drugs were available to control thyrotoxicosis this complication was common. Now that all patients are under control at the time of surgery a thyroid storm is rare. The term storm is very accurate; the patient has a rapid pulse, is restless, and has a high temperature with sweating, diarrhoea and delirium.

Voice Change

Voice change is one of the most dreaded complications of thyroid surgery. Patients whose voice is their livelihood should discuss in great detail with their physician the need for thyroidectomy. Minor voice changes are not uncommon and are usually transient. Significant hoarseness is usually temporary (4%) but is permanent in less than 1% of patients. Damage to the recurrent laryngeal nerve can result in paralysis of the vocal cords. A study in 2001 showed that the use of a laryngeal mask airway in parathyroid and thyroid surgery, along with fibre optic laryngoscopy and nerve stimulation in the operative field, can lead to better identification and preservation of the recurrent laryngeal nerves. Mr Lynn is convinced that nerve monitoring is essential.

The problem of voice change following thyroidectomy is discussed in detail in the section - The Thyroid and the Voice

Bilateral Recurrent Laryngeal Nerve Damage - click to enlarge

Failure to Control the Thyrotoxicosis

Recurrent thyrotoxicosis represents surgical failure and it occurs in 2-4% of patients after a traditional subtotal thyroidectomy. The modern "fashion" of total thyroidectomy for thyrotoxicosis reduces the incidence of recurrent thyrotoxicosis to zero but has a significant rate of hypoparathyroidism in non specialist hands. Recurrent thyrotoxicosis is managed by radioactive iodine and rarely further surgery.

Damage to the Parathyroids

The parathyroids may be inadvertently removed or bruised.I believe that the preservation of the parathyroids is still one of the most difficult tasks in thyroid surgery.Temporary damage is very common and despite previous thoughts permanent damage around 4% must be expected especially in total thyroidectomy for Grave's disease.Parathyroid damage results in a low blood calcium with tingling in the feet, hands and around the mouth. In severe cases there is spasm of the fingers and hands.It is usually transient but may need long term calcium and vitamin D replacement. For years Mr Lynn has insisted that patients are made Vitamin D replete prior to total thyroidectomy. In 2009 a study from Hammersmith Hospital London confirmed his view. The Hammersmith group presented to the BAETS their findings in relation to Vitamin D status and the incidence of post-operative hypocalcaemia (low serum calcium). These workers confirmed that patients with a low pre-operative Vitamin D were at greater risk of a problem with post-operative hypocalcaemia than those patients who were Vitamin Dreplete. In addition patients with a low pre-operative Vitamin D needed to stay longer in hospital than patients with a normal vitamin D. The management of long term hypocalcaemia is difficult. There is often poor compliance by the patients of ingestion of unpalatable calcium tablets and excessive intake of calcium inhibits thyroxine absorbsion from the gut. Where at all possible attempts should be made to limit as much as possible calcium replacement. If the calcium is above 2 mmol with a reasonable parathyroid hormone level no extra calcium is indicated. If the calcium is less than 2 mmol and the parathyroid hormone level is undetectable long term calcium replacement will be needed with alpha calcidol starting at 1 microgramme daily. Serum calciums should be checked weekly. It must be remembered that there is a risk of nephrocalcinosis and annual kidney utrasounds should be performed as well as 24 hour urinary calcium excretion. Be watchful for iatrogenic hypercalcaemia

Swallowing Problems

For the first few days after surgery swallowing difficulty is common. It is rarely persistent, but on occasions there is a feeling of persistent strangulation. This latter feeling is fortunately very rare (four cases seen personally in 30 years).

Low Thyroid State (Hypothyroidism)

If the entire thyroid is removed then the patient will always become hypothyroid and need thyroid replacement. If part of the thyroid is left behind it is difficult to predict the long-term need for thyroid tablets. It is therefore essential that all such patients be checked regularly for hypothyroidism (blood test of T3, T4 and TSH). Hypothyroidism may occur many years after surgery and patients should be followed up for life.

Wound Sinus

In the past the use of silk sutures to tie off blood vessels sometimes resulted in a small abscess around the suture that would discharge to the skin causing a tract from the suture to the skin. This is called a sinus. Surgeons no longer use silk or non absorbable sutures in the neck and sinus formation is now very rare. The problem of sinus formation was known to the famous surgeon Sir Joseph Lister. In 1881,Lister gave the Presidential Address to the Clinical Society of London,he described performing a thyroidectomy using his antiseptic technique,unfortunately catgut which is absorbable was not available and he used non absorbable "hempen". One of his trainees William Henry Dobie whose grandaughter Liz Woodd-Walker a GP now retired to Devon recorded the incident in his surgical notebook. The patient suffered from a granuloma and persistent sinus which only healed when the suture material extruded itself from the sinus. Following this experience Lister taught that silk and other non absorbable materials should never be used in the neck! It took over a hundred years for for Lister's views to be widespread.A retrospective study from Cardiff in 1987 confirmed Lister's views; it showed a 8% incidence of granuloma formation in 526 thyroidectomies performed with silk sutures as compared to zero with absorbable material. Using silk sutures inside the neck with subsequent granuloma and sinus formation is now considered poor practice.

Infection

We support the recent NICE guidelines on prevention and treatment of surgical site of infection. We now advise a shower the evening of the surgery or on the day of surgery. We agree that shaving is not always essential. If hair removal is essential it should be performed using a single-use electric clippers rather than a razor on the day of surgery. We prepare the skin with an aqueous or alcohol based antiseptic. We never incise the skin with a diathermy knife (this has a high incidence of infection).

Ourrate of infection is well below 1%, generally reported rates are as high as 2.9% (Danish Poster Presentation, P Christiansen et Al 2009 IAES Adelaide Australia 2009).

Pre-operatively all patients are swabbed for MRSA infection which if present is irradicated prior to surgery.

We do not usually use adhesive drapes unless they are impregnated with iodine in a non iodine sensitive patient. Patients are allowed to shower in 24 hrs after surgery. All patients are swabbed pre-operatively for MRSA from the skin and nose. Despite these measures Infection can occur although it is rare. I had recently a single case of alpha haemolytic streptococal infection that responded well to out patient drainage and anti-biotics. This single case was a sharp reminder to the rare but real danger of hospital infection. Thankfully we have never had a clinically significant MRSA problem in my unit. Patients are advised my Mr Lynn to be very vigilant and to insist their visitors wash their hands prior to physical contact. All hospital rooms are equiped with a antiseptic hand wash device.

Unsightly Scars

Unsightly scars are unusual occurring in less than 1% of patients. They occur in three separate circumstances. Firstly, in black skin where lumps occur in the scar (keloid). Secondly, in thin necks the scar can stick to the underlying structures producing a tethering effect on swallowing. Thirdly, unsightly scars can occur after wound infection.

The surgeon has damaged the upper skin flap. This should not happen.
The patient was awarded damages - click to enlarge