History & Examination
- Full anaesthetic, medical and surgical history
- Assess for symptoms and signs of thyroid disease
- Assess for presence of associated endocrine disorders as part of MEN
- Assess for symptoms of airway compromise:
- Dyspnoea
- Dysphagia
- Stridor
- Exacerbation of symptoms on lying flat
- Examine the goitre:
- Size and degree of tethering
- Inability to feel bottom of goitre suggests retrosternal spread
- Evidence of tracheal deviation
- Examine for complications:
- Superior vena cava (SVC) obstruction
- Horner’s syndrome
- Pericardial or pleural effusions
Investigations
- Laboratory investigations:
- Thyroid function tests – ensure patient is euthyroid prior to surgery
- Full blood count – serious adverse haematological effects of concurrent antithyroid medications
- Two group and save samples – potential for blood loss
- Calcium levels – provides baseline as levels may fall post-operatively
- Clinical investigations:
- Nasendoscopy: document vocal cord function
- Respiratory flow volume loops (spirometry) – can help characterize fixed obstruction but rarely used
- ECG – to determine arrhythmias associated with thyroid disease
- Imaging investigations:
- Ultrasound – first-line diagnostic imaging of thyroid nodule to determine size, location and suspicious features
- CXR – may demonstrate tracheal deviation / retrosternal goitre
- CT scan – performed if concerns regarding tracheal narrowing or deviation
Optimisation
- Primary goal of optimization is to render the patient euthyroid:
- Usually achieved with carbimazole or propylthiouracil
- Lugol’s iodine may be given for 10 days to reduce vascularity of the gland
- Multidisciplinary approach usually key: endocrinologist, surgeon, cardiologist, radiologist and anesthesiologist
- In emergency surgery may not be possible to achieve euthyroid state:
- Cardiac symptoms should be controlled with beta-blockade
- Temperature management may be necessary
- On the day of surgery, usual antithyroid medications should be administered except for Carbimazole