Goiter

Map the airway on CT before induction - CT is the preferred imaging study: it characterizes the mass, detects tracheal deviation, quantifies tracheal compression, and shows the relationship to the aortic arch and great vessels. A tracheal dimension of 10 mm or less is the threshold at which surgical intervention is required — read the number yourself rather than accepting "trachea deviated" from a report. Chest x-ray adds the upper mediastinal mass and deviation but cannot substitute; ultrasound cannot see the intrathoracic portion at all, because the waves will not cross bone or air.

Get a flow-volume loop - Substernal goiter blunts the loop with near-equal flow limitation in inspiration and expiration and flattening of both limbs, the signature of a fixed upper airway obstruction. Loops can be abnormal in a patient who reports no symptoms, and they separate goiter-driven dyspnea from COPD, asthma, or heart failure in a population that is usually in its sixth decade or later.

Pemberton sign at the bedside - Have the patient raise both arms above the head. Facial congestion, bulging neck veins, hoarseness, or dyspnea is a positive sign and means the gland corks at the thoracic inlet. Arm-elevation spirometry with flow-volume loops makes the same finding objective. It also tells you something practical: arms-up positioning on the table can worsen the obstruction.

Stridor tells you where the obstruction is - Stridor is high-pitched and heard more on inspiration, and points to obstruction outside the chest cavity — distinct from expiratory wheeze from lower airway obstruction. Exertional dyspnea is the most common obstructive complaint, followed by choking sensation, cough, and stridor.

Document the cords before you touch the airway - Any hoarseness, and any patient going for thyroidectomy, warrants preoperative voice assessment with flexible fiberoptic laryngoscopy or nasendoscopy. Recurrent laryngeal nerve injury during thyroidectomy causes vocal cord paresis or paralysis, and without a documented baseline you cannot tell a new injury from an old one.

Plan equipment to the measured narrowing - A trachea that is deviated and narrowed on CT may not accept the tube you would normally reach for. Have smaller-diameter tubes and a video laryngoscope in the room, and site the level of narrowing from the CT so you know how far the tube has to pass to get beyond it.

Establish thyroid status - Measure TSH, free T4, and T3 to determine whether the patient is thyrotoxic, subclinically toxic, euthyroid, or hypothyroid. Nodular goiters can be asymptomatic with a normal TSH or thyrotoxic with a low TSH, and toxic multinodular goiter peaks in the sixth to seventh decade. Prolonged thyrotoxicosis produces ventricular thickening and raises cardiac morbidity and mortality, so the thyroid panel and the ECG belong together.

Iodine before surgery - An inorganic iodine solution is given 7 to 10 days before surgery to prevent thyroid storm. Confirm it was actually taken, not just prescribed.

Nerve-monitoring tube changes the intubation - When recurrent laryngeal nerve monitoring is planned, the patient is intubated with a nerve-monitoring endotracheal tube whose sensors must sit between the vocal cords, and monitor function is confirmed after intubation per the manufacturer's instructions. Tube depth is set by the electrodes, so reconfirm the monitor after any repositioning of the head or tube.

Sternotomy is a real possibility - An extracervical approach is usually needed for primary retrosternal goiters, goiters wider than the thoracic inlet, recurrent goiters, intrathoracic thyroid cancer, and tissue invading the retrotracheal or retroesophageal space. A wide trachea with a narrow inlet points toward sternotomy. Plan access, lines, and blood availability for that possibility rather than the transcervical best case.

Extubation is the high-stakes moment - Retrosternal goiter surgery carries higher rates of transient and permanent unilateral and bilateral recurrent laryngeal nerve injury than cervical goiter surgery. Bilateral injury produces acute airway obstruction requiring tracheostomy. Extubate deliberately, with the equipment and the surgeon still available.

Watch calcium afterward - Hypocalcemia from hypoparathyroidism is a common postoperative complication, and permanent hypoparathyroidism is more frequent after retrosternal than cervical goiter surgery. Follow ionized calcium and watch for the neuromuscular signs in the first postoperative day.

Goiter is enlargement of the thyroid gland. The gland normally grows anteriorly and laterally, where only thin strap muscles, fat, and skin resist it. When it grows inferiorly through the thoracic inlet it becomes a substernal (retrosternal) goiter, and the space runs out. Thyroid function may be normal (nontoxic), overactive (diffuse toxic goiter, or Plummer disease — toxic multinodular goiter), or underactive.

The perioperative problem is mechanical. Tracheal deviation or compression is reported in 35% to 73% of substernal goiters; the recurrent laryngeal nerve, the esophagus, and the jugular and other venous structures can all be compressed, producing hoarseness, dysphagia, and neck vein engorgement. Less often the cervical sympathetic chain is compressed, giving Horner syndrome, or the superior vena cava. Substernal goiter is four times more common in women, usually presents after age 50, and carries a 9% to 13% risk of malignancy.