N746 RESPIRATORY DISEASE PRESENTATION ANGELA HICKEY UNIVERSITY OF PENNSYLVANIA SCHOOL OF NURSING ANESTHESIA MANAGEMENT OF MEDIASTINAL MASSES

MEDIASTINAL MASSES The mediastinum is defined as “the space between the lungs” Borders: Thoracic inlet superiorly, Diaphragm inferiorly, Sternum anteriorly, Spine posteriorly, and Pleural spaces laterally. Divided into compartments: Anterior, Middle, and Posterior 2/3 of mediastinal masses in adults = anterior High risk d/t location to the airway and great vessels. Compress the pulmonary artery and heart Increase atelectasis and obstruct airflow CNS changes (d/t obstructed venous drainage in the upper thorax). GA very dangerous = Collapse of airway= Obstruction Supine position Induction of anesthesia Positive-pressure ventilation

MEDIASTINAL MASS Common AM tumors- ”The 4 T’s”-Thymoma, Thyroid, Teratoma, and “Terrible” Lymphoma Symptoms of Anterior Mediastinal Mass: Neuro: syncope Resp: Stridor, Hoarseness, Cyanosis, Orthopnea, Inability to lie flat, Cough (esp when supine), Chest pain or fullness CV: Sweating, Jugular Vein Distention, Superior vena cava syndrome Treatment: depends on type of tumor and symptoms- typically a combination of surgery, chemo, and/or XRT Surgical procedures can be diagnostic(eg. biopsy for grading), palliative/supportive (eg. stenting of trachea or SVC), or treatment via complete resection of tumor

SVC SYNDROME Venous engorgement of the upper body when the SVC is compressed Typically caused by cancerous tumors Most common- Lung and Non-Hodgkin Lymphoma S/S: dilation of collateral veins of the upper part of the thorax and neck, edema and rubor of the face, neck, upper torso and airway, SOB, HA, visual distortion or altered mentation.

ANESTHETIC MANAGEMENT Ideally- Local Anesthesia in all circumstances with minimal sedation If GA necessary: GOAL= Maintain spontaneous ventilation to retain normal airway- distending pressure gradients and maintain airway patency. Have rigid bronchoscopy at bedside Ability to turn patient lateral or prone in case of collapse Consider cannulation for ECMO if tumor large or symptomatic

MEDIASTINOSCOPY A rigid scope is passed through the suprasternal notch. Why is it used? For direct visualization of the mediastinal space and to sample paratracheal and mediastinal lymph nodes at various levels in order to stage intrathoracic cancers, lymphoma. Relatively contraindicated in pts with prior mediastinoscopy, tracheal deviation, radiation, thoracic aneurysm or SVC obstruction d/t increased risk of vessel puncture from anatomic distortion

MEDIASTINOSCOPY Pre-op Considerations RESP: IMPORTANT evaluations to anticipate potential for airway collapse 1. CT/TEE/MRI - to delineation of mass size and effects 2. Respiratory system assessment: Must be thorough to asses for respiratory tract compression Symptoms positional? Compare when supine Asymptomatic or vague signs (dyspnea, cough, hoarseness, or chest pain) Wheezing (mechanical obstruction vs bronchospasm) If SVC syndrome: may have significant airway edema 3. PFTs- helpful-> not always reliable for predicting airway collapse CV: Vascular compression (Right heart, PA, SVC) Hypotension, hypoxia, SVC syndrome MS: Assess for myasthenic syndrome (resistance to depolarizing agents and increased sensitivity to NDMRs.) Neuro: If SVC obstructed, will have increased ICP. Pts with pre-existing carotid disease are at increased risk for stroke

MEDIASTINOSCOPY Pre-op (con’t) BP monitoring- must occur on left arm (whether invasive or non- invasive) with or without right arm monitoring Pulse oximeter placed on right arm ga x 1(one in lower extremity with SVC syndrome) Blood products for transfusion available in OR CVP with PA line for those with large mediastinal masses (placed via femoral vein with SVC syndrome) Rigid Bronchoscopy on standby Difficult airway cart with flexible bronchoscopy on standby Femoral cannulation for highest-risk patients

MEDIASTINOSCOPY Induction Awake fiberoptic using local anesthesia preferred Allows direct visualization of obstruction t/f ETT placed distal Monitors the effects of positional changes on the trachea/bronchii Alternatively, Inhalation induction with Sevo/O2 ETT should be reinforced if known airway compression Semi-Fowler’s position Maintain spontaneous ventilation Avoid muscle relaxation, if necessary utilize shorter acting only after guaranteed PPV

MEDIASTINOSCOPY Intra-Op Considerations ***Acute brachiocephalic compression with the scope Results in hypoperfusion of the R common carotid -> CVA Innominate artery compression is monitored via pulsatile waveform in the Right upper extremity using pulse oximetry Left radial arterial line so that blood pressure can be monitored in the event of brachiocephalic avulsion Most common COMPLICATION*** Hemorrhage d/t laceration of great vessel Other complications: Venous Air Embolism- risk higher d/t HOB at 30 degrees and when spontaneously ventilating Tracheal or Esophageal compression/Injury Bradycardia (vagally-mediated d/t compression on trachea or great vessels), Arrhythmias, Cardiac Arrest Thoracic Duct Injury

MEDIASTINOSCOPY Post-op Considerations Monitor for Complications Left recurrent laryngeal nerve damage Phrenic Nerve Injury Pneumothorax/Pneumopericardium/Pneumomediastinum Tracheamalacia

CASE STUDY: LMA USE IN PATIENT WITH MEDIASTINAL MASS Preop: 64 yo F with recurrent 10 x10 x12 cm lung cancer tumor encroaching the great vessels and trachea with significant tracheal compression and deviation not amenable to surgery. Scheduled for palliative tracheal stent to relieve the airway obstruction 2/2 worsening dyspnea and cough. Induction, Maintenance, Post-Op Large bore IV, right radial A-line Inhalation induction (70% nitrous/30% O2/Sevo then 100% O2/Sevo) in Semi-recumbent position Classic LMA #5 placed while spontaneous ventilation maintained GA with O2/Sevo supplemented with low-dose Propofol (25-50mcg/kg/min) Tracheal stent was deployed with immediate imporvement of tidal volumes. LMA successfully removed at the end of the procedure and the patient recovered from the surgery uneventfully in the PACU. Classic LMA provided better access to the subglottic compression The large internal diameter and lack of epiglottic elevator bars allow easy passage of the stent loader and bronchoscope without interruption of ventilation Disadvantages: Airway not secure and always the possibility the tumor could compress the trachea distal to the LMA IMPT = The authors had a rigid bronch available and the cardiopulmonary bypass team on standby

REFERENCES Barash, P. G., Cullen, B. F., & Stoelting, R. K. (2009). Clinical anesthesia (6th ed.). Philadelphia: Lippincott Williams & Wilkins. Blank, R.S. & deSouza D.G. (2011). Anesthetic management of patients with an anterior mediastinal mass: Continuing Professional Development. Can J Anesth, 58: Butterworth, J., Mackey, D., & Wasnick, J. (2013). Morgan & Mikhail’s clinical anesthesiology (5 th ed.). New York, NY: McGraw-Hill. Nagelhout, J. & Plaus, K. (2014). Nurse anesthesia (5 th ed.). St. Louis, MO: Elsevier Saunders. Rajagopalan, S. (2014). Anesthetic management of a large mediastinal mass for tracheal stent placement. Rev Bras Anestesiol,