Risk of Aerosolization and Droplet Formation in Patients with
Tracheostomy
COVID-19 can spread by direct contact, droplet, and likely also
aerosolization.[4,8,9] Aerosolization refers to
the process by which small particles are formed and dispersed in the
air.[10] It is important to distinguish
aerosolization from droplet formation, which refers to the process by
which fluids in the form of large droplets come into direct contact with
another person thereby causing infection. In contrast to droplets,
aerosolized SARS-CoV-2 does not require personal contact with the source
patient and has been shown to remain viable in the air for upwards of
three hours.[4] For this reason, procedures or
patient groups with increased risk of aerosolization may significantly
increase viral transmission.[11,12] Some common
procedures known to lead to aerosolization include intubation,
tracheotomy, airway suctioning, nebulizer treatments, manipulation of
oxygen masks, and non-invasive positive pressure
ventilation.[13,14]
It remains unclear exactly how much and how often patients with
tracheostomy and TL are aerosolizing. The amount likely differs based on
unique patient factors. Based on data from the 2013 SARS-CoV-1 outbreak
and early data from the current COVID-19 pandemic, it is likely that
patients with fresh tracheostomy or TL are at significantly higher risk
of spreading viral particles compared to other patients given high rates
of aerosolizing procedures and equipment, including suctioning
requirements, nebulizer treatments, open stomas, and open humidification
with trach collar.[11,15,16] In addition to the
risk of aerosolization, there is also an increased risk of droplet
formation given frequent productive coughing in recent surgical
patients. Given the increased risk of aerosolization and droplet
formation in conjunction with the high rates of undocumented infections
and asymptomatic carriers, precautions for all patients with
tracheostomy and TL may be indicated.[17]