Health, Media Criticism, Science And Society, Technology and Society

Are We Using Ventilators Wrong?

29 Comments

Do patients need oxygen rather than pressure? Are we doing more harm than good with the ventilators?

[Via Kate McMillan, who has more]

[Update mid-afternoon]

This didn’t get much attention in comments a few days ago, but let’s try to boost the signal. I just did, on Twitter:

29 thoughts on “Are We Using Ventilators Wrong?”

  1. Finnish people are known to like very hot saunas.
    And they don’t seem to doing worse than the rest of Europe

      1. Which means that the air temperature in the lung will be the same as that entering the nose and mouth. Having a 100% humid air at a given temperature means that it won’t cool (by evaporative cooling, the major driver) as it traverses the respiratory system. And since people could withstand 130 F wet-bulb temperature air, albeit with a lot of discomfort, the idea that this would treat coronavirus is not completely inane. But there are a lot of things to try first.

      2. Not what talking about, I mean dry sauna which Finns, like too close to 100 C, as compared how most people like take a dry sauna. Or governments will limit a sauna’s heat lower than what some Finns like.

      3. Saunas actually have very low humidity for most of a typical use cycle. It’s only at the end of one’s sauna that water is poured over hot rocks to suddenly raise the humidity. This also raises the human body’s subjective sensation of heat, a phenomenon known to sauna-takers as “The Devil’s Arm” because that’s what it feels like has just been laid across one’s shoulders.

  2. IDK, case reports talk of patients on high flow oxygen that go on to true ARDS picture, and in Seattle the standard reported was if patients were on high-flow or BiPAP to just intubate and ventilate patients because they were going to deteriorate to that point. Thankfully, I haven’t seen any yet with severe distress.

  3. The human body warms cold air and cools hot air on the way to the lungs. You would need to breath air considerable warmer than 56C to get it that warm in your lungs. Likely not feasible.

      1. I didn’t check far enough. I just looked at the picture and posted.

        I assume you have seen the update by Kate’s by her DrD.

    1. “The temperature in Finnish saunas is 80 to 110 °C (176 to 230 °F), usually 80–90 °C (176–194 °F), and is kept clearly above the dewpoint despite the vaporization of löyly water, so that visible condensation of steam does not occur as in a Turkish sauna.”
      https://en.wikipedia.org/wiki/Finnish_sauna

  8. Doogie Howser doesn’t strike me as a real doctor. He appears to be broadcasting from a recent college graduate’s apartment, and is – well, not exactly William Jennings Bryan, if you atchkay my iftdray. The other article is interesting, and belongs in the mix (but isn’t fully convincing).

    I have virtually every single risk factor for a very bad outcome if I become infected, so I’m really looking at everything I see and read very critically. Fortunately, where I live the probability of me even seeing someone who is infected is 0.017% (assuming the real infection rate is 10 times the number of known cases).

  10. The suggestion to breath hot air in order to raise lung temperatures is absolutely terrible, wrong and dangerous in all ways.

    TLDR; You can’t easily get internal lung temperature to 56C, even breathing directly from an oven. If you COULD do this, you would irreparably damage the lungs and kill people.

    Even when you breathe OVEN AIR (350+ C) the air temperature by the time it gets to the TRACHEA is down to 50C and that’s in a lab animal (so, smaller than a human).

    https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1934101/?page=6

    Futher, this study says that alveolar instability started at 52C and resulted in less than 50% lung function. This would, to say the least, not help.

    https://www.ncbi.nlm.nih.gov/pubmed/7129978

    1. From the first study: “All experiments were conducted under anesthesia induced by the intravenous or intraperitoneal injection of sodium pentathol.” So at least there was that.

  11. I have issues with a lot of this source material.
    I’m sticking to sources I believe to be reliable to avoid junk science. Such sources as the preprint servers etc. Anecdotal evidence I see here I do not find convincing. There is a lack if quantitative as well as qualitative rigor.

    Primum non nocere.

  12. Well listening scott adams who endlessly goes on about ventilators.
    So I need a distraction.
    “At present, U.S. hospitals have access to roughly 200,000 ventilators; however, the American Hospital Association estimates more than 900,000 people could need the devices in a worst-case scenario, per abcnews.go.com. Furthermore, projections from the Centers for Disease Control and Prevention (CDC) indicate that millions of Americans infected with COVID-19 may require intensive care.”

    So, 200,000 and there are 52 weeks in year and probably average time in terms CCP virus one needs a bed is 7 days:
    200,000 times 52 = 10.4 million.
    But one could say the 200,000 ventilators are needed for non-CCP virus patients.
    Maybe that is true, but that means 200,000 are not available. And Scott knows in an emergency it possible to spilt one machine for two patients, yet he whines about it. And whining about no one telling him how is needed and how we have.
    But important part of this is the projection of how CCP patients which need a ventilator. And above:
    “900,000 people could need the devices in a worst-case scenario,”
    So, about 10% of people who go to hospital because they have CCP virus, need ventilator.
    Or what called active cases and serious case, and portion of serious cases need a ventilators. And roughly speaking or on average most people don’t live long when put on a ventilator {for any kind of reason- which could be related to the post title: “Are We Using Ventilators Wrong?” ]
    Anyways, New York State stats of “yesterday”:
    Total active cases: 106,672
    Oh they changed it. I got sort of back up:
    US total cases: 309,238
    Total serious cases: 8,702
    Or four countries in Europe:
    Total active cases: 310,588
    Total serious cases: 21,612‬

    So if have 1 million active cases in hospitals you will have
    if in Europe about 60,000 serious cases whereas US has less than 1/2 of 60,000 per million.
    And if have 60,000 cases it seems less the 40,000 need ventilators.

    Now interesting question is could we have 1 million active cases of CCP virus at all hospitals in the US at the same time. Or seems to crowded with 309,238 which cases tested and affirmed to have the CCP virus. It’s total counted and tested since beginning of pandemic.
    I suppose it’s pretty useless number to understand Hospital capacity and whereas total serious cases would get a clue of number at a hospital. And from here:
    https://www.worldometers.info/coronavirus/country/us/
    they remove that statistic and replaced with testing stats {which made happy the first time it appeared. But that before learned they removed total serious cases.
    I think I am getting more sympathetic to scott’s whining.
    I will go back to it.

    1. Look at South Korea’s worldometer stats. It’s the only country on Earth whose plot of “Active Cases” plot is trending downward – and very steeply. I did a quick trendline, and it’s going down at 189 cases per day.

      1. There is this guy, I’ll call him Patrick, who wrote a book that I will call “The Rocket Company.” There is this other guy who works for the space agency in South Korea who invited the author for a visit.

        The author of The Rocket Company was puzzled why his hotel in South Korea had what appeared to be blast doors between sections and other seemingly extreme safety measures not seen in the US.

        I suggested that much of the population of South Korea is within artillery range of North Korea, and that the South Koreans living in a high level of civil-defense preparedness since the 1953 Korean Armistice might have something to do with it.

        As to mask wearing and other measures, maybe the South Koreans have been practicing for some time?

  13. On the suggestion in a comment at Small Dead Animals that the problem is the virus stripping hemoglobin of iron atoms, that should be trivially easy to check just by taking a blood sample and measuring how well it transports oxygen. If the blood is being stripped, it should behave like very old blood where the red blood cells have largely died, and acting like a non-Newtonian fluid that’s bad at transporting oxygen instead of a non-Newtonian fluid that’s good at it.

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