What is the approach for retrosternal goitre (goiter) surgery?

Surgical Approach for Retrosternal Goiter

The cervical approach is the primary and preferred surgical method for retrosternal goiter removal, successfully accomplishing resection in approximately 90-93% of cases, with sternotomy or extracervical approaches reserved only for specific high-risk anatomical features identified on preoperative CT imaging. 1, 2

Preoperative Planning and Imaging

CT imaging is mandatory for surgical planning and superior to ultrasound for evaluating substernal extension and defining the degree of tracheal compression 3. The preoperative CT scan should specifically assess:

• Longitudinal extension of the goiter - extension to or below the aortic arch significantly increases the likelihood of requiring a thoracic approach (p<0.0001) 4
• Laterality and anatomical relationships - CT findings correlate well with intraoperative findings in over 97% of cases 4
• Loss of fat planes - indicates adherence to surrounding structures and increased risk of requiring extracervical approach 4
• Presence of ectopic intrathoracic thyroid tissue - absolute indication for sternotomy 2
• Tracheal deviation and compression 3

MRI is an alternative but has more respiratory motion artifact, making CT the preferred modality 3.

Surgical Approach Algorithm

Cervical Approach (First-Line - 90-93% of Cases)

The transcervical approach should be attempted first when:

• Approximately 50% of tumor volume is above the thoracic inlet 1
• Extension does not reach the aortic arch 4
• No ectopic intrathoracic thyroid tissue is present 2
• Goiter weight is anticipated to be less than 500-600g 2

Technical considerations for cervical approach:

• Mean operation time is approximately 115 minutes 1
• Average blood loss is approximately 54 mL 1
• Postoperative hospital stay averages 5.4 days 1

Indications for Sternotomy or Extracervical Approach (7-10% of Cases)

Sternotomy or combined approach is required when:

• Ectopic intrathoracic thyroid tissue is present 2
• Extension reaches or extends beyond the aortic arch or tracheal carina 2, 4
• Very large goiters (>500-600g, particularly >800g mean weight) 2
• Posterior mediastinal location extending retrotracheally beyond the aortic arch 5
• Recurrent disease 4
• Malignant disease with mediastinal involvement 4
• Loss of fat planes on CT indicating adherence to vital structures 4

For posterior mediastinal goiters extending beyond the aortic arch, a combined transcervical and lateral thoracotomy approach may be superior to median sternotomy 5.

Critical Intraoperative Considerations

Recurrent Laryngeal Nerve (RLN) Protection

Routine RLN visualization and dissection is the surgical cornerstone for reducing nerve injury during retrosternal goiter surgery 6. Retrosternal goiters present unique RLN challenges:

• Distortion and elongation of the RLN caused by large goiters with retrosternal extension is an important risk condition favoring RLN palsy 6, 3
• Complete visualization and nerve dissection from thoracic inlet to larynx is considered the gold standard 6
• Avoid blind ligatures or coagulation, especially in the tracheoesophageal groove 6
• Use intermittent rather than continuous traction to prevent stretch injury 6
• Pay particular attention to Berry's ligament area where most RLN lesions occur (within <2 cm tract) 6

Intraoperative nerve monitoring (IONM) can be considered for selected high-risk patients, particularly to avoid bilateral palsy by stopping the operation if signal loss occurs on the initial side 6. However, IONM is not considered "standard of care" as systematic reviews have not demonstrated statistically significant differences between visualization alone versus visualization plus IONM 6.

Anatomical Variations to Anticipate

• Precocious division of extralaryngeal RLN branches - common anatomical variation requiring careful dissection 6
• Non-recurrent laryngeal nerve (0.3-1.6% incidence, more common on right side) - may mimic arterial branches 6
• Nerve intertwining with inferior thyroid artery branches - complicates dissection and hemostasis 6

Perioperative Complications and Management

Expected Complication Rates

Transient complications:

• Transient RLN palsy: 6.25% (most recover within 1-3 months) 1
• Transient hypocalcemia: 13-20.5% 1, 2
• Transient hypoparathyroidism: 14.3% 1

Permanent complications:

• Permanent RLN palsy: 1.8% 1, 2
• Permanent hypoparathyroidism: 3.7% 2
• Postoperative bleeding: 5.6% 2
• Respiratory complications requiring tracheostomy: 1.8% 2

Postoperative Airway Management

All patients require vigilant postoperative monitoring given the risk of hematoma formation (0.45-4.2% incidence) 6:

• Bedside emergency box must be available containing wound opening supplies 6
• Emergency front-of-neck airway equipment (scalpel, bougie, tracheal tube) must be readily available 6
• Minimum monitoring includes: wound inspection, early warning scores, pain scoring, and awareness for subtle signs (agitation, anxiety, difficulty breathing, discomfort) 6

If airway compromise from hematoma occurs, use the SCOOP approach at bedside:

• Skin exposure
• Cut sutures
• Open skin
• Open muscles (superficial and deep layers)
• Pack wound 6

Special Considerations for High-Risk Patients

Patients with large, long-standing goiters may have:

• Tracheal deviation 6
• Tracheomalacia - may cause airway collapse upon extubation requiring urgent reintubation 6
• Retained secretions impairing swallowing 6

Anesthetic vigilance is critical - deflate endotracheal tube cuff at time of retractor placement, then reinflate gently to avoid tracheal injury 6.

Surgeon Experience and Referral Considerations

Surgeon experience significantly determines surgical outcomes - studies show increased RLN injury incidence among surgeons performing fewer than 45 high-risk cases per year 6. Retrosternal goiter surgery should be performed by skilled surgical teams familiar with its unique pitfalls, with thoracic surgery backup available for the 7-10% of cases requiring extracervical approaches 2.