Emergency application of extracorporeal membrane oxygenation in a pediatric case of sudden airway collapse due to anterior mediastinal mass: A case report and review of literature

Abstract

Mediastinal masses can compress the respiratory or cardiovascular system, especially when anteriorly located. Obtaining histological material for diagnosis poses a challenge due to the major risk of cardiorespiratory collapse following anesthetic procedure. Our case shows the utility of rescue with venovenous extracorporeal membrane oxygenation (VV-ECMO) after occurrence of such an event and demonstrates the feasibility of administering chemotherapy during VV-ECMO. A 4-year-old boy was referred to the pediatric oncology clinic of our hospital after a large mediastinal mass was observed on chest radiography ordered due to persistent cough. Computed tomography of the thorax revealed a 100×85 mm mass in the anterior mediastinum, surrounding the heart, and showed that there was compression to the trachea, bronchiole, and vascular structures. Percutaneous needle biopsy accompanied by ultrasonography was planned for diagnostic purposes. Low-dose ketamine and midazolam were administered for procedural sedation in the operating room. After the biopsy procedure, the patient developed sudden airway obstruction requiring intubation. Despite 100% oxygen support with a mechanical ventilator, pulse oximeter saturation remained below 80%. Chest X-ray revealed total collapse of the left lung, and the patient's oxygen saturation did not increase with selective left bronchial intubation. Bi-caval dual-lumen ECMO cannula was placed in the internal jugular vein and VV-ECMO was initiated, resulting in swift improvement in hypoxemia. The patients's anterior mediastinal mass shrank rapidly and left lung improved with chemotherapy. The patient remained on ECMO for a total of 9 days and was extubated 2 days after ECMO termination, followed by discharge to the pediatric oncology ward on the 20th day of pediatric intensive care unit stay. It is well known that large, anteriorly-located mediastinal masses carry a considerable risk of causing cardio-pulmonary collapse during procedures involving anesthesia. All life-saving options, including emergency ECMO, should be available before any planned invasive procedures in these patients.

Figure 1

Initial chest radiography shows a wide mediastinum. The lower tracheal was pushed to the right side (black arrow).

Figure 2

Initial chest computed tomography scan. On image (a), superior anterior mediastinal mass encases pulmonary arteries, trachea, arcus aorta, and bronchus in transverse view. The black arrow indicates the trachea at this point of maximal compression. The predictive cross-sectional area mesurement is estimated to be 40%. The white arrow points to the mediastinal mass, which is homogeneous nature. On image (b), mediastinal mass compresses left mainstream bronchus and trachea (blue arrows) and pushes the trachea to the right (black arrow) in coronal view.

Figure 3

Chest radiography shows total left lung collapse.

Figure 4

Avalon Elite^® is a bicaval dual lumen venovenous ECMO cannula inserted through the right internal jugular vein. The distal end of the cannula is located in the cavoatrial junction (black arrow).

Figure 5

Chest radiography after ECMO decannulation. ECMO: Extracorporeal membraneoxygenation.