March 31, 2020
I have been thinking a lot about patients with COVID-19 and the pulmonary pattern that they develop. This disease process has been categorized like ARDS, but the reality is it is not like "typical" ARDS. Lung compliance is often normal in these patients, and many patients are not in respiratory distress despite low O2 saturations. Patients can have a bizarre hypoxemia that does not correlate with their symptoms. I have even read reports of patients looking comfortable and speaking in full sentences with oxygen saturations in the 40 – 80% range. There are also more traditional patients in respiratory distress with similar oxygen saturations. This is a situation where we cannot treat a patient based solely on a number - pulse oximetry may not be a reliable marker of respiratory compromise.
Approaches to oxygen supplementation have stressed minimizing aerosolization of viral particles by avoiding HFNC and NIV. This appears to be a fear-based statement as opposed to an evidence based one. If we go straight from nasal cannula to intubation, we will simply run out of ventilators. Then, more challenges present themselves like rationing mechanical ventilation and trying to figure out how to split ventilators due to the lack of resources.
Finally, I have yet to find a study that shows a mortality rate <50% once a patient is intubated. Maybe a better way to deal with these patients is an intermediary step using HFNC or CPAP while proning patients while they are awake, before considering intubation. In this post, I want to review some evidence to support my thoughts on this and, just assume that in every scenario we are discussing full PPE (eye protection, N95/PAPR, gown, gloves, and face shield)....Read More