Extubation and the Risks of Coughing and Laryngospasm in the Era of Coronavirus Disease-19 (COVID-19)

Abstract

The coronavirus disease-19 (COVID-19) pandemic has prompted new interest among anesthesiologists and intensivists in controlling coughing and expectoration of potentially infectious aerosolized secretions during intubation and extubation. However, the fear of provoking laryngospasm may cause avoidance of deep or sedated extubation techniques which could reduce coughing and infection risk. This fear may be alleviated with clear understanding of the mechanisms and effective management of post-extubation airway obstruction including laryngospasm. We review the dynamic function of the larynx from the vantage point of head-and-neck surgery, highlighting two key concepts: 1. The larynx is a complex organ that may occlude reflexively at levels other than the true vocal folds; 2. The widely held belief that positive-pressure ventilation by mask can "break" laryngospasm is not supported by the otorhinolaryngology literature. We review the differential diagnosis of acute airway obstruction after extubation, discuss techniques for achieving smooth extubation with avoidance of coughing and expectoration of secretions, and recommend, on the basis of this review, a clinical pathway for optimal management of upper airway obstruction including laryngospasm to avoid adverse outcomes.

Keywords: aerosol-generating procedures; covid-19; deep extubation; extubation; functional anatomy of the larynx; laryngospasm; novel coronavirus; partial airway obstruction; stridor; upper airway obstruction.

Figure 1. Digital rendering of the larynx

The larynx is a complex functional organ that serves as the guardian of the airway, and is located between the third and sixth cervical vertebrae. (Artist: Sebastian Kaulitzki, via Shutterstock, Inc., with permission.)

Figure 2. Anatomy of the larynx

Laryngeal closure may occur at three levels from superior to inferior: the laryngeal inlet between the hyoid bone and the thyroid cartilage, the vestibular folds or false cords, and at the glottis between the vocal folds. (Image by Alila Medical Media, via Shutterstock, Inc., with permission.)

Figure 3. Clinical management of upper airway obstruction

The successful diagnosis and management of upper airway obstruction depend on rapid analysis of whether the obstruction is complete or partial, and application of appropriate stepwise actions to open the airway and ensure ventilation.