The management of a patient with tracheal compression undergoing combined resection of an anterior mediastinal mass and aortic valve replacement with coronary artery bypass graft surgery: utility of the laryngeal mask airway and Aintree intubation catheter.

T HAS LONG BEEN recognized that the presence of an anterior mediastinal mass can lead to respiratory and cardiovascular collapse. Importantly, the severity of airway compromise may not be apparent in the awake patient. There have been numerous reports in the literature of life-threatening complications or death during anesthetic induction, maintenance, and emergence, as well as in the early postoperative period. 1,2 Symptoms attributable to anterior mediastinal masses include airway compression with obstruction, obstruction of the major vessels and heart, and superior vena cava syndrome. 3,4 Airway management in these patients can prove challenging and demands proper planning and communication on the part of the anesthesia and surgical teams. This case describes the airway management of a high-risk patient with significant tracheal narrowing and a large retrosternal goiter undergoing combined resection of this mass with major cardiac surgery. CASE REPORT A 54-year-old woman presented with a 3-day history of shortness of breath, cough, and an inability to lie flat because of worsening dyspnea. Past medical history was significant for morbid obesity (weight 112 kg, height 162 cm), emphysema, angina, hypertension, non‐insulin-dependent diabetes mellitus, anxiety/depression, hyperlipidemia, osteoarthritis, gastroesophageal reflux, gastroparesis, and a more than 30 pack/year current smoking history. Two years earlier, she had undergone emergency tracheostomy for upper-airway obstruction after a dental infection. This was complicated by acute respiratory distress syndrome requiring mechanical ventilation for 2 weeks. Medications at the time of presentation included lasix, potassium chloride, prednisone, Nexium (AstraZeneca LP, Wilmington, DE), Lipitor (Pfizer Inc, New York, NY), Singulair (Merck, Whitehouse Station, NJ), Diovan (Novartis, Cambridge, MA), Lexapro (Forest Laboratories, New York, NY), reglan, Allegra (Sanofi Aventis, Bridgewater, NJ), Vioxx (Merck), Paxil (SmithKline Beecham, Philadelphia, PA), metoprolol, and albuterol. A computed tomography scan of the chest showed an enlarged thyroid gland extending down into the superior mediastinum and surrounding the upper trachea. The trachea was maximally narrowed to 5 mm at the level of the thyroid cartilage (Fig 1), with intrathoracic extension of airway narrowing. A transthoracic echocardiogram showed a left-ventricular ejection fraction of 55%, left-ventricular hypertrophy, mild mitral regurgitation, severe aortic insufficiency, and a small pericardial effusion. Cardiac catheterization revealed a 70% proximal left circumflex coronary artery stenosis. Pulmonary function tests showed the following: forced expiratory volume in 1 second of 1.3 L (61% predicted), forced vital capacity of 1.8 L (68% predicted), forced expiratory volume in 1 second/forced vital capacity of 72.3%, and FEF25-75 (forced expiratory flow from 25% to 75% of vital capacity) of 0.75 L/s (28% predicted). Spirometry showed flattening of the expiratory limb of the flow-volume loop (Fig 2). Laboratory data including complete blood count, electrolyte panel, coagulation profile, and thyroid function studies were all within normal limits. The patient was premedicated intravenously with midazolam, 1 mg, glycopyrollate, 0.2 mg, ranatidine, 50 mg, and metaclopromide, 10 mg. Preoperatively, her airway was anesthetized with 4 mL of nebulized 4% lidocaine. Intraoperative monitors included the standard American Society of Anesthesiologists monitors, a brachial arterial catheter, and a pulmonary artery catheter that was placed after intubation. Bilateral glossopharyngeal nerve blocks were performed by using 1% lidocaine. For anesthetic induction, she was maintained in 30 degrees of reverse Trendelenburg positioning and preoxygenated for 5 minutes. Eighty milligrams of propofol were administered, and a no. 4 laryngeal mask airway (LMA) was easily inserted. The patient maintained spontaneous respiration during this time, and sevoflurane was incrementally administered to 2.3% end-tidal concentration. With the patient breathing spontaneously, a fiberoptic bronchoscope loaded with an Aintree intubation catheter (Cook Critical Care, Bloomington, IN) was introduced into the trachea via the LMA by using a swivel adaptor to allow continued delivery of oxygen and sevoflurane. The Aintree intubation catheter is an airway-exchange catheter with a 4.8-mm internal diameter that can be loaded onto a 4.0-mm fiberoptic bronchoscope. The vocal cords were sprayed with 1% lidocaine through the suction port of the bronchoscope, the airway was examined for degree of patency, and the catheter was easily advanced across the narrowed portion of the trachea. The LMA was then removed, and a 7.0 armored endotracheal tube was gently advanced over the intubating catheter past the obstruction. After median sternotomy, the patient underwent total thyroidectomy, breathing spontaneously. End-tidal CO2 ranged between 40 and 50 mmHg, and PaCO2 measured during spontaneous ventilation was 47 mmHg. The surgeon confirmed by direct palpation that there was no tracheomalacia. Pancuronium was then administered, and the patient underwent uneventful aortic valve replacement and single-vessel coronary artery bypass grafting to the left circumflex coronary artery with cardiopulmonary bypass. She remained intubated overnight and was extubated the next morning after having met standard extubation criteria and the demonstration of a leak around the endotracheal tube with cuff deflation. Her postoperative course was uneventful, and she was discharged on postoperative day 6 with significant improvement in her respiratory complaints.