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UChicago doctors see ‘remarkable’ success using ventilator alternatives

uchicagomedicine.org

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Re: UChicago doctors see ‘remarkable’ success using ventilator alternatives

#61

Post by caymanjim »

DenisM wrote: post #50

So about CPAP / BiPAP? If all one needs it to push air down the lungs a CPAP can produce a lot of pressure. Anyone knows enough about it?

The main problem with CPAP in a clinical setting is that it's not sealed and filtered like a proper ventilator, so it aerosolizes and disperses virus at high pressure. It's the same concern that they mention in this article about dispersal and the need for negative pressure rooms and more PPE. It's being used on some patients who aren't bad enough to require intubation.

Re: UChicago doctors see ‘remarkable’ success using ventilator alternatives

#62

Post by piannucci »

DenisM wrote: post #50

So about CPAP / BiPAP? If all one needs it to push air down the lungs a CPAP can produce a lot of pressure. Anyone knows enough about it?

First-- and I'm sure you weren't suggesting this, but I feel I need to mention-- it's extremely dangerous to pressurize a person's lungs above the surrounding environment[1]. Not to mention that pressurizing the inside of the throat could pressurize the middle ear and blow out your eardrums.

Second, I'm not a physician, I'm a physicist. What follows is for curiosity's sake.

I suspect that the goal is to maximally enrich the patient's airstream in oxygen, whenever it is that they happen to breathe in. In a patient with fluid-filled alveoli, the surface area available for diffusion of oxygen into the bloodstream is greatly diminished. Additionally, the distance that oxygen needs to diffuse before it reaches hemoglobin is increased: rather than just the lining of alveoli and capillaries, it has to first dissolve into the fluid gunk filling the space, then diffuse through the fluid, then pass through the lining of the alveolus and capillary. To top it off, water doesn't have great solubility for oxygen, and atmospheric air is mostly nitrogen anyways.

Each of these passive transport phenomena occurs at a rate that depends on the gradient (roughly...) of available O2. This concentration is greatest in the air, and lowest in the bloodstream adjacent to the alveoli, where hemoglobin binds up oxygen. One way to increase the rate of dissolution and diffusion is to increase the concentration gradient. That means enriching the airstream in O2.

[1] https://en.wikipedia.org/wiki/Barotrauma#Pulmonary_barotraum...

Re: UChicago doctors see ‘remarkable’ success using ventilator alternatives

#63

Post by james-mcelwain »

jonkho wrote: post #38
not_a_moth wrote: post #24

Earlier quoted context omitted.

Yes, rather absurdly, I learned about him like a month ago on ZeroHedge when they started following him; he was brushed off for weeks, his message being, "Look at patient behavior, this is not actually ARDS, our ventilator strategy is probably wrong." Crazy to think that so many doctors around the world, experts, and policy makers didn't really question the fundamental nature of the disease, and perhaps telling that…

Also, how does this affect the actual death rate numbers in NYC if unnecessary deaths caused by outcomes of ventilator use are factored into the picture? Could change the picture quite drastically.

It's not like we're going around incubating healthy people -- you have to be pretty sick to get put on a ventilator. Even if the treatment turns out to be a net negative, most of these patients didn't have very good odds in the first place, so it's pretty unlikely it would affect the death rates "drastically."

Re: UChicago doctors see ‘remarkable’ success using ventilator alternatives

#64

Post by caymanjim »

mrfusion wrote: post #22

I heard on Reddit that Medicare pays 3x more for intubation. Can anyone find a source?

Hospitals are losing money on covid patients, and the more treatment they require (ICU, ventilator, medication), the more the hospital is losing. They do get paid about three times more for an intubated patient, but they lose more money too.

Hospitals make their profit off voluntary procedures like shoulder and knee surgeries and the constant flow of voluntary tests and procedures ("I just want to get this checked out"). They lose a lot of money when people spend three weeks in the ICU.

This is especially true when a huge percentage of the patients are Medicare or completely uninsured. Privately insured patients with good policies are better, but they still aren't getting rich off those people.

I have no sympathy for the hospital systems or the entire medical industry that has created a massive bureaucracy full of perverse incentives, exploitation, overbilling, and accounting games, but in this particular situation, even with the massive federal handouts, they're not making bank.

Re: UChicago doctors see ‘remarkable’ success using ventilator alternatives

#65

Post by 9oliYQjP »

theobeers wrote: post #5

One of the most active figures in this debate has been a New York doctor named Cameron Kyle-Sidell. He frequently posts interesting sources on Twitter: https://twitter.com/cameronks

Here's an interesting video from another MD who provides some much needed nuance to Kyle-Sidell's insights.

https://youtu.be/Fz2gyhto-iI?t=767

Re: UChicago doctors see ‘remarkable’ success using ventilator alternatives

#66

Post by pests »

nerdponx wrote: post #35
not_a_moth wrote: post #24

Earlier quoted context omitted.

Yes, rather absurdly, I learned about him like a month ago on ZeroHedge when they started following him; he was brushed off for weeks, his message being, "Look at patient behavior, this is not actually ARDS, our ventilator strategy is probably wrong." Crazy to think that so many doctors around the world, experts, and policy makers didn't really question the fundamental nature of the disease, and perhaps telling that…

What I don't understand about this is - didn't China figure this all out already?

I distinctly remember months ago of a Chinese doctor in China claiming this same thing. I thought it was a bit far fetched at the time but I'm getting incredible deja vu with this new release.

Re: UChicago doctors see ‘remarkable’ success using ventilator alternatives

#67

Post by jplayer01 »

pests wrote: post #66
nerdponx wrote: post #35

Earlier quoted context omitted.

What I don't understand about this is - didn't China figure this all out already?

I distinctly remember months ago of a Chinese doctor in China claiming this same thing. I thought it was a bit far fetched at the time but I'm getting incredible deja vu with this new release.

It's not just the Chinese. Doctors have been concerned about the abnormally high death rate for ventilators for months too. I've been seeing comments to the effect of looking for alternatives to ventilators because there were indications that did more harm than good. I guess not every hospital had this idea, but I know the sentiment was around for a while.

Re: UChicago doctors see ‘remarkable’ success using ventilator alternatives

#68

Post by ineedasername »

I wonder how they decide which patients would get the cannula instead of a ventilator?

Otherwise, intubation w/ a ventilator generally requires some form of sedation-- I wonder if that sedation has an impact on the body's ability to fight back.

Re: UChicago doctors see ‘remarkable’ success using ventilator alternatives

#69

Post by wl »

ineedasername wrote: post #68

I wonder how they decide which patients would get the cannula instead of a ventilator? Otherwise, intubation w/ a ventilator generally requires some form of sedation-- I wonder if that sedation has an impact on the body's ability to fight back.

From what I've read here and elsewhere, they're putting everyone they would normally put on a vent on high flow. They only move to the vent when not doing so in the near term would likely result in death. That means, among other things, that they tolerate lower SpO2 levels than they would otherwise.

Re: UChicago doctors see ‘remarkable’ success using ventilator alternatives

#70

Post by _startingover »

achillesheels wrote: post #57
DanielBMarkham wrote: post #15

Earlier quoted context omitted.

It's an excellent point. Learning is not the same as science, and we need randomized trials to actually be sure of anything. Unfortunately, in the middle of a pandemic, that's not going to happen with enough speed to prevent a lot of people dying. The perfect can be the enemy of the good enough. We don't have to guess or learn about the mass of an electron; that's been well-established through great lab work. But not…

And unfortunately, there are doctors that will not make a move on an experimental therapy without it going through IRB approval, as I am learning with my own efforts at introducing a portable nebulizer biocidal therapy. Some will not take chances unless they see safety data first - they will let their patients and colleagues die first. As a former biomedical engineering researcher, this pandemic has been profoundly e…

Yeah, the clinical culture isn’t really designed to handle a novel infectious disease. Of course patients are going to die.
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