Asian Cardiovasc Thorac Ann 2006;14:e17-e18
© 2006 Asia Publishing EXchange Ltd
Tracheobronchial Obstruction as a Result of Mediastinal Mass
Victor TT Chao, MD,
Darren WT Lim, MD,
Miriam Tao, MD,
Agasthian Thirugnanam, MD,
Heng Nung Koong, MD,
Chong Hee Lim, MD
National Heart Centre, Singapore
For reprint information contact: Chong Hee Lim, MD Tel: 65 6436 7598 Fax: 65 6224 3632, Email: limch88{at}hotmail.com, National Heart Centre, Mistri Wing, 17 Third Hospital Avenue, 168752 Singapore.
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ABSTRACT
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A 21-year-old woman presented with almost complete extrinsic airway obstruction due to a massive mediastinal tumor. Venovenous extracorporeal membrane oxygenation support for 3 days with concurrent chemotherapy allowed time for tumor shrinkage, ventilation via the endotracheal route, and subsequent successful extubation on the fifth day.
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INTRODUCTION
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Mediastinal mass presenting with airway obstruction is a rare entity. Challenges include timely control of the airway. Obtaining a tissue diagnosis is a priority in guiding further management. Obstruction of the distal trachea, carina, and bronchi can render endotracheal intubation and tracheotomy ineffective.1 Difficulty in airway access necessitates cardiopulmonary bypass or extracorporeal membrane oxygenation (ECMO) support pending measures to establish an airway.2–4 A dramatic tumor response in the case of lymphoma, with relief of airway symptoms, can be achieved with chemotherapy and corticosteroids, with or without radiotherapy.1
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CASE REPORT
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A 21-year-old female university undergraduate presented with symptoms of progressive shortness of breath of 1 month’s duration. Her symptoms were worse at night, with partial relief by lying on her side. She consulted two general practitioners who diagnosed asthma. She subsequently presented to our Emergency Department with stridor. Chest radiography in anteroposterior and lateral views showed a large anterior mediastinal mass with distal tracheal constriction from the level of vertebra T2. Computed tomography (Figure 1
) show a massive homogenous soft tissue mass that occupied the superior and anterior mediastinum, measuring 13.6 x 8.3 cm in axial dimensions, and extending 16 cm in craniocaudal length. The mass displaced the great vessels and aortic arch posteriorly and reduced the distal trachea to a 0.5 cm slit. The proximal left and right main bronchi were also compressed. Incisional tissue biopsy was attempted using local anesthesia with light sedation. The patient decompensated toward the end of the procedure and was intubated with a size 7 endotracheal tube, but mean airway pressures were high (50 to 60 mm Hg) and adequate arterial oxygenation could not be obtained. Emergency rigid bronchoscopy, tracheal dilatation, and stenting were attempted. The luminal stenosis did not respond to dilatation, and the plastic stent failed to expand against the compressed distal trachea after deployment. In view of the ventilatory difficulties, it was decided to support the patient on venovenous ECMO.
Both common femoral veins were cannulated with Bio-Medicus 21F (30') and 19 F (17') femoral cannulas (Medtronic, Minneapolis, MN, USA) sited in the right atrium and the left common iliac vein, respectively. A Carmeda heparin-coated circuit with an I-3500 oxygenator-heat exchanger (Medtronic, Minneapolis, MN, USA) was used in conjunction with a Capiox SP45 centrifugal pump head (Terumo Corporation, Tokyo, Japan). An immediate improvement in SaO2 was seen with the pump running in the femoral-atrial direction, with flow rates of up to 3.5 L·min–1. The lung rest ventilatory settings were kept at a tidal volume of 250 mL and a respiratory rate of 8 breaths per minute. Anticoagulant was administered to achieve an activated clotting time of 200 seconds. The patient was pulsed with high-dose steroids, cyclophosphamide, and vincristine on day 1, based on preliminary frozen-section histology reports. Following confirmation of the tissue type on day 2, a chemotherapy regime for high-grade B cell Burkitt’s lymphoma was started. The patient recovered gradually and uneventfully. By day 3, she was able to breath on her own, generating a tidal volume of 600 mL and oxygen saturation of 99% on a fraction of inspired O2 of 50%, with peak airway pressures of 30 mm Hg. The ECMO support was withdrawn on the same day, and she was extubated on day 5. A flow-volume loop study showed relief of obstruction along the major airways. She was found to be in National Cancer Institute stage A after further investigation. She achieved partial remission after completing 2 courses of chemotherapy.
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DISCUSSION
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In cases of suspected major airway compromise, any attempt to obtain tissue under general anesthesia can lead to disaster.5 Ventilatory failure occurs almost immediately after induction with a general anesthetic, as a result of loss of spontaneous respiratory effort, the supine posture accentuating airway compression, or elimination of glottic regulation of airflow by endotracheal intubation.6 One proposed strategy is to avoid using general anesthesia or sedation if possible, and exploring alternative methods of diagnosis.5 Computed tomography-guided percutaneous core biopsy under local anesthesia is one option. In cases where respiratory compromise is imminent, empirical radiotherapy should be considered.
In the event of respiratory failure, timely support can be obtained with ECMO or cardiopulmonary bypass.2–4 Surgical or percutaneous access can be obtained, depending on the scenario, and adequate flow rates can be achieved using portable units. Venoarterial ECMO has been used successfully in similar situations in the past.2 However, in the setting of a patient with good myocardial function, we feel that venovenous ECMO effectively delivers supplemental oxygen to the circulation with minimal side effects. In the patient who presents with airway obstruction secondary to a mediastinal mass, anticipation and prevention of potential respiratory complications and readiness to treat them appropriately are the important aspects of management.
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REFERENCES
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- Hessan H, Houck J, Harvey H. Airway obstruction due to lymphoma of the larynx and trachea. Laryngoscope 1988;98:176–80.[Medline]
- Rosa P Jr, Johnson EA, Barcia PJ. The impossible airway: a plan. Chest 1996;109:1649–50.[Abstract/Free Full Text]
- Belmont MJ, Wax MK, DeSouza FN. The difficult airway: cardiopulmonary bypass—the ultimate solution. Head Neck 1998;20:266–9.[Medline]
- Stewart AS, Smythe WR, Aukburg S, Kaiser LR, Fox KR, Bavaria JE. Severe acute extrinsic airway compression by mediastinal tumor successfully managed with extracorporeal membrane oxygenation. ASAIO J 1998;44:219–21.[Medline]
- Jeffery GM, Mead GM, Whitehouse JM. Life-threatening airway obstruction at the presentation of Hodgkin’s disease. Cancer 1991;67:506–10.[Medline]
- Prakash UB, Abel MD, Hubmayr RD. Mediastinal mass and tracheal obstruction during general anesthesia. Mayo Clin Proc 1988;63:1004–11.[Medline]
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ABSTRACT
INTRODUCTION
