An Alternate Approach to Anesthetic Management of Central Airway Tumors

Sir, We read with great interest the article “The shared airway tracheal mass excision” published in the recent issue of Annals of Cardiac Anesthesia.[1] We congratulate the authors on successfully managing such a challenging case. We agree that such patients are ideally managed with extracorporeal membrane oxygenation (ECMO), which ensures oxygenation and ventilation during the debulking/excision of the tumor. The concern arises when such a patient presents in respiratory distress, ECMO facilities are not available, and the patient is not stable enough to be transported to an ECMO center. We routinely manage such patients at our center, and we share our experience of managing such cases.[2] The patient is counselled about the anesthetic plan and debulking procedure. The anesthetic plan includes provision for oxygenation, ventilation, anxiolysis, anesthetizing the airway, and the availability of micro-laryngeal surgery endotracheal tubes in sizes 4 and 5, a jet ventilator, and rigid bronchoscopes of 5 and 6 mm. Initially, the patients receive intravenous dexamethasone 4 mg and nebulization with 100 μg adrenaline in 4 ml saline to reduce airway edema and vascular congestion. Thereafter, oxygen is delivered through a face mask, and dexmedetomidine infusion is started at 0.2 μg/kg/h. While infusing dexmedetomidine, the breathing rate and pattern are monitored. In the operating room, the airway is nebulized with 5 ml (4%) lignocaine, a 10% lignocaine spray is applied to the oropharynx, and a transtracheal injection of 4 ml (4%) lignocaine is administered. Dexmedetomidine infusion is continued at 0.2 to 0.5 μg/kg/h. Once the airway is anesthetized, an I-gel of size 4 (for an adult woman) or 5 (for an adult male) is placed and connected to the breathing circuit. A swivel connector with an opening for fiber-optic bronchoscope is placed between the breathing circuit and the I-gel. The patient breathes spontaneously with 4 to 5 cm H2O CPAP support from the anesthesia circuit. A fiberoptic bronchoscope is passed through the swivel connector, which carries a cryo cautery, or cautery, an electrocautery, or a laser snare to debulk the tumor [Figure 1]. A tamponading balloon is also passed beside the fiberscope to tamponade the bleeders if required. In case it is difficult to control bleeding, the I-gel, fiber-optic bronchoscope, cautery and tamponading balloon are removed, and a pediatric rigid bronchoscope is placed in the trachea beyond the tumor for tamponading and ventilation. Once the tumor is debulked and adequate room for ventilation is available, general anesthesia with a muscle relaxant is administered for the rest of the procedure. At this point, the interventionalist has the option to switch to a rigid bronchoscope for the remaining debulking. Although the described procedure appears straightforward, several issues need to be considered carefully. There is a spectrum of presentation of the patients based on the severity of airway compromise. The most vulnerable patients are dyspneic at rest and exhibit features of respiratory failure. In such patients, oxygenation and ventilation are maintained because of spontaneous ventilation. The negative intrapleural pressure generated during spontaneous breathing exerts radial traction on the airways and keep them open, a loss of negative intrapleural pressure secondary to anesthesia, sedation and muscle relaxation can result in a decrease in airway diameter and near-total or total airway occlusion at the tumor.[3] In this situation, to sustain oxygenation and ventilation, manual forceful ventilation or jet ventilation becomes mandatory, which often result in dynamic hyperinflation, pneumothorax, and cardiovascular collapse. The key points for managing such cases are to counsel the patient, ensure airway anesthesia, initial debulking through airway conduit, and keeping spontaneous ventilation until adequate debulking is achieved; thereafter, the interventionalist can continue with an I-gel as a conduit or switch to rigid bronchoscopy for completion of the debulking.Figure 1: Flexible bronchoscope, loaded with cautery and a tamponading balloon, was passed through the airway channel of a size 5 Igel. The rigid bronchoscopes (12 mm and 13 mm ID) are shown for comparing the diameter of the I-gel with the adult rigid bronchoscopeFinancial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.