Monday, April 6, 2020

**Serious Post**: Doctor advises on potential lifesaving corona virus breathing technique.

(After the two links, the text at the bottom of this e-mail is *not* a "normal" conversation but simply highlights from a forum thread wherein these are some major points. Some people would be familiar with some of this, I am not, so just passing on information. The whole point is if someone gets this, the survival rate is much, much, much higher, if they can avoid getting pneumonia. These being ways to break up the "virus" from overtaking/infecting the lungs...if that makes sense. )

Doctor advises on potential lifesaving corona virus breathing technique.

Airway Clearance Techniques (ACTs) from the Cystic Fibrosis Foundation.


Concurs with this Cystic Fibrosis Foundation video on airway clearance techniques. The aim is to get mucus out of the small airways, then the large airways, of your lungs so you can cough it up. Lying on your front uses gravity to help pull mucus from your small airways.

In the hospital we are lying people on their fronts who are on a breathing machine with severe COVID. It's called "prone ventilation".

This makes so much more sense now. I have a job that requires me to be there when an individual is in the hospital. He was in the ICU with pneumonia and a flu and a bunch of other illnesses and he was on a ventilator. The nurses would come and rotate him every hour or couple of hours. Never seen that before because I've seen drug OD/hangings that require ICU intubation but never seen them rotated.

Yes, we primarily do it for ARDS (acute respiratory distress syndrome) as mentioned below, which can be caused by COVID, bacterial pneumonia, trauma, or any thing else that causes the lungs to become inflamed and fill up with fluid. The thought is that prone ventilation reduces lung compression (atelectasis) and improves blood flow (perfusion).

It’s not just prevention of atelectasis probably. It’s all about V:Q which is the ratio of ventilation (air getting to that area) to perfusion (blood flow to that area). Basically the ventilation and perfusion of your lungs is variable: the ventilation can be decreased if that part of your lung fills with something (pus in pneumonia, water in ards from “capillary leak”), perfusion is affected by things like gravity (more blood flow to the lower parts of your lung).

In severe lung disease the fluid (pus, water, whatever) also follows gravity and so when you’re lying on your back, as most patients are, the fluid starts to fill the areas of lung closer to your back which decreases the ventilation to that area. Unfortunately blood flow also obeys gravity and so there is more blood flow going to those areas as well. This results in a low V:Q ratio which is very inefficient and leads to worsening oxygen levels (ie hypoxia) as deoxygenated blood is preferentially going to poorly ventilated lung areas.

Proning (ie putting the patient on their stomach) increases this ratio because it allows the increased perfusion to go to the front of the lungs that have relatively less fluid and more ventilation. It also then allows the accumulated fluid to redistribute to the front of the lungs and so then you flip them over again (ie supinate). You do this daily, something like 12 hrs on each side. It can have a dramatic effect on hypoxia and keep someone alive long enough to get through whatever the precipitant of their lung disease is.

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