Airway Management and Tracheotomy
Patients presenting with acute airway obstruction should be managed as if they are COVID-19 positive as diagnostic testing is not feasible in an emergent clinical situation. All clinical personnel should wear enhanced PPE. The use of high-flow nasal cannula is contraindicated in patients with unknown, suspected, or positive COVID-19 status due to high risk of virus aerosolization.24,25 Extreme caution should be utilized when performing awake fiberoptic intubation due to instrumentation of the nasopharynx and the potential for aerosol generation, however intubation via any means is preferable to emergent tracheotomy. A high-efficiency hydrophobic filter should be placed between the face mask and breathing circuit or reservoir bag, the patient should be pre-oxygenation, and rapid sequence intubation techniques should be used to minimize viral particle aerosolization.25 When available, video laryngoscopes should be used to maximize intubation success rate and disposable laryngoscopes to minimize infectious spread.24,25
To minimize intubation time and exposure to the oropharynx, the 2015 Difficult Airway Society Guidelines26 should be followed with the exception that intubation should be performed only by the most senior practitioner available using enhanced PPE. Second-generation laryngeal mask airways should be used, if indicated, as these provide an improved seal compared to first-generation devices.25 If a “can’t intubate, can’t oxygenate scenario” is declared, emergent extra-corporeal membrane oxygenation (ECMO) may be preferred over emergent surgical airway to reduce the risk of virus aerosolization, though this may not be readily available. Indications for primary emergent tracheotomy include obstructive laryngeal lesions, severe trismus precluding the ability to perform direct laryngoscopy, massive oropharyngeal bleeding, other conditions precluding intubation, and other emergent conditions anticipated to require long-term means to secure the airway where ECMO would not be appropriate.
When caring for a patient with unknown, suspected, or positive COVID-19 status, clinical staff should be limited to essential personnel (i.e. senior attending anesthesiologist, experienced attending surgeon, senior surgical resident/clinical fellow, surgical technologist, and registered nurse) fully equipped with enhanced PPE in a negative pressure operating room with HEPA filtration 24. Technical pearls to consider when performing tracheotomy in a patient with unknown, suspected, or positive COVID-19 status include avoiding electrocautery usage to minimize aerosolization of viral particles, advancing the endotracheal tube prior to incising the anterior tracheal wall to prevent cuff rupture and maintain a closed circuit, and holding ventilation until placement of cuffed non-fenestrated tracheotomy tube is confirmed with end-tidal CO2 and lung sound auscultation. Further details regarding safe tracheotomy have been outlined by Wei et al. and Harrison et al .27,28
Postoperatively, the tracheotomy tube should not be changed or manipulated until the COVID-19 status has been addressed with infectious disease. Routine tracheotomy tube care as delineated by ENT-UK should includes maintenance of a closed circuit, exclusively in-line suctioning, frequent cuff leak checks, and avoiding humidification.28 At this time elective tracheotomy is contraindicated for patients with unknown COVID-19 status and should only be performed once COVID-19 status has been determined with appropriate quarantine and the merits of tracheotomy are discussed as it is a high-risk, aerosol-generating procedure.29Likewise, percutaneous dilation tracheotomy is contraindicated in patients with unknown, suspected, or positive COVID-19 status. This contraindication is due to the need for simultaneous bronchoscopy (itself a high-risk procedure), and longer period of exposure to an open tracheostomy site during serial dilation resulting in increased risk of virus aerosolization.
There is limited information regarding management of tracheotomy patients no longer requiring ventilator support in the setting of COVID-19. The use of filters over the open tracheotomy, such as humidification-moisture exchangers (HMEs) may be beneficial and reduce aerosolization. Alternatively, Chan et al. describe using a closed circuit system identical to that used for a mechanical ventilator for all tracheotomy patients, including those not requiring ventilator support.4 Ultimately, the choice of device may be dependent on the COVID-19 status of the individual patient and the ability to provide appropriate isolation to minimize the spread of aerosols.