Adjunctive measures before definitive intervention of COVID-19
patients (Table 2)
Non-invasive ventilation such as HFNC has been utilized widely in
COVID-19. Initial high flow oxygen should be given immediately for
patients with obvious respiratory distress or weak cough ability. In the
University of Chicago, HFNC combined with prone positioning have shown
remarkable results in the treatment of COVID-19 patients in respiratory
distress. In patients who are clinically stable, a lower oxygen flow can
be started, gradually increasing the oxygen flow if necessary. The use
of HFNC could pre-emptively prevent patient deterioration, hence
avoiding intubation and mechanical ventilation. A surgical mask should
also be worn by the patient to reduce the risk of virus transmission
through droplets or aerosols. However, it should still be noted that
elderly patients are vulnerable for failed HFNC, requiring other
intervention such as intubation in order to maintain respiratory
requirements.
Although CPAP/BiPAP machines units with an exhalation filter could
theoretically support SARS/COVID-19 patients with respiratory failure,
there is a high incidence of CPAP/BiPAP mask leak which may result in
inadvertent leak of aerosolized virus. If used out of appropriate
airborne/droplet isolation, there are increased transmission risks.
CPAP/BiPAP machines may also lead to delayed deterioration in patients,
resulting in a greater incidence of emergent intubations. Hence,
CPAP/BiPAP machines should be avoided in patients with COVID-19 and
should only be considered in appropriate airborne/droplet isolation
settings on a case by case basis.