The Infection That’s Silently Killing Coronavirus Patients | Hacker News Reader

The Infection That’s Silently Killing Coronavirus Patients

nytimes.com

79 pointsvo2maxer51 comments

This was already reported in China since the very early days of the infection. People would come in with critically low spO2 that seemed to have no problems breathing but would then rapidly collapse.

China switched to a system of centralized quarantine where people were put under medical supervision no matter how mild their case was and their spO2 was checked twice a day[1]. Anyone with spO2 < 93% was put on supplemental oxygen immediately rather than waiting for clinical signs.

The American practice of allowing people to recover at home and make a self-determination of when they require hospitalization is likely causing many more excess deaths.

Here's a Rachel Maddow video from March 12th explaining all of this: https://www.msnbc.com/rachel-maddow/watch/how-a-country-seri...

[1] Page 72 of https://gmcc.alibabadoctor.com/prevention-manual/reader?pdf=...

The President should use the Defense Production Act to get pulse oximeters to everyone. In our household we have been following Dr. John Campbell's videos on youtube for sometime now. Dr. Campbell suggested in February that everyone should have a pulse oximeter at home and we got one. My friends who have been looking to get one now can't seem to find them (the affordable ones)anywhere.

There's something weird going on with COVID-19 and oxygen levels. I've seen lots of doctors posting that they're seeing patients with crazy low oxygen levels - like in the 30s which is usually fatal but these patients were conscious and responsive.

Whether it's messing with the way we read blood oxygen levels, or there's something else funky going on, I don't know. But it's weird.

I don't have a link on me right now but I was reading about COVID and chloroquine and in some patients COVID actually attacks and binds to the hemoglobin, preventing blood from being able to carry O2 or CO2 (which then leads to multiple organ failure and the like). Cloroquine can prevent that from happening but (I am not a medical professional, this is not professional advice, this is just what I read) only if taken early on before COVID sets in.

Either way, this virus is causing some people's bodies to do weird, disastrous things, and others have no symptoms whatsoever.

Maybe this [1] was the link.

[1] https://chemrxiv.org/articles/COVID-19_Disease_ORF8_and_Surf...

The whole (hydroxy)Cloroquine thing is interesting to me because it seems to depend a lot on Zinc. And the existing data doesn't seem to track it. So we are left with little to contemplate.

They said that they can function with the oxygen levels that low because the lungs are still compliant at expelling the carbon dioxide which is not typically the case with respiratory disease. I read in a different article that it’s perhaps because the virus is actually striking the vascular system causing restriction of blood vessels in the lungs which restrict air supply while the lungs themselves function.

So, treat like athsma/cystic fibrosis, with long-acting bronchodilators?

That would make sense of the "all OK" -> "suddenly just about dead" transition. And it wouldn't need to lower O2 absorption by much to get this effect because if CO2 is being expelled normally, the body won't engage its normal can't-breathe responses so the O2 level drops virtually unchecked.

I've read about successful treatment just with hyperbaric oxygen which would also make sense here.

> like in the 30s which is usually fatal but these patients were conscious and responsive.

These meters are calibrated around the normal range of values. Once they get out of that they become very inaccurate. So a reading in the 30s is probably not actually an 02 sat in the 30s.

Interesting, because that would correlate with the high death rate. Sedation, intubation, respirator, is a low success path. Staving it off has value. And it feels like there is a path there.

These lower level interventions don't make all that much of a difference. As the disease progresses your lung capacity reduces. If we put some made up numbers to it, it would look like:

0-50%: Can breathe on their own with increasing difficulty

50-55%: Can survive with O2, BiPap, CPAP, etc.

55-80%: Can survive with intubation

80%+: Dead

Each individual patient will progress to a certain point and then either recover or die. The number that will progress to the O2, BiPap, CPAP, etc. level and then recover is relatively small since it's a pretty narrow band where it is effective.

AFAIK, most places are skipping the O2, BiPap, CPAP stuff because they use pressurized air. That generates a lot of droplets/aerosols and poses a significant transmission risk. Since there's a relatively small chance that the patient will recover on those interventions they skip them and go straight to intubation.

Here is a great explanation: https://www.youtube.com/watch?v=nO4xgcIaPeA

There are three main causes of hypoxemia (low blood o2): 1) "V/Q" (volume/flowrate), where uneven flow of blood carries unoxegenated blood past alveoli faster than it can oxygenate, 2) "Shunt" where blood flows through the lungs without being able to exchange gasses at all 3) "Diffusion Abnormality" - usually seen in COPD, this is where the membrane between alveoli and the capillaries becomes thicker or different. CO2 can diffuse through a thicker membrane more easily than oxygen, so that can explain some of the findings other posters are discussing.

Nothing peer reviewed on this yet, though we have techniques for analyzing exactly whats happening in the lungs by injecting inert gasses to the body and measuring how they leave.

I'm unable to view the article but is this NY clinician saying the same thing? https://youtu.be/k9GYTc53r2o

The gist is: 'Covid appears not to be an ARDS but a disease most resembling the symptoms of high altitude sickness'.

There's been a suggestion that the virus is able to dissociate the Fe in haemoglobin and thus cripple its O2-carrying function. Higher levels of free iron would likely be one result but have seen no data on this.

http://archive.is/QSBfc

TLDR: silent hypoxia - meaning that their blood oxygen level is low.

But people don't notice it yet, because CO2 levels are not building up as they would with "normal" breathing problems.

I like that they included saturation numbers so that those of us who have oxymeters (e.g. from skydiving) can self-check.

It is really interesting since this is one of these parameters one can check easily and cheap (OXI meters are around 100 euro). And they're still available ATM.

Any advice on an oxymeter to purchase, or components/features to look for? They all seem to be the same, but vary in price from $20-$300. Reviews on websites are just garbage.

There are ones that clip onto a finger and also ones that you can wear while sleeping. I have one of the wearable ring ones (Wellue/O2Ring/Viatom, etc) and am happy with it. My oxygen levels are good through the night and my resting heart rate is much lower than I expected it would be.

Search Reddit, lots of doctors and med students discussing which of the cheap ones work. Nearly all are sold out though. I bought this one last night based on Reddit feedback for $35 but it's already sold out: https://www.amazon.com/gp/product/B01HSAG8BE/ref=ppx_yo_dt_b...

If you've got $300 to spare, this one is allegedly FDA approved: https://www.masimopersonalhealth.com/products/mightysat-fing...

Thanks! A place called Medkioskinc.com apparently still has stock of those (at least they did ten minutes ago when I looked), for anyone reading this thread.

My S8 has a "Samsung Health" app, that measures Oxygen Saturation under the "Stress" section. It uses the sensor next to camera (also used for Heart Rate). I've no idea how accurate it is though.

Some googling and I found a related paper: "Accuracy of Smartphone-Based Pulse Oximetry Compared with Hospital-Grade Pulse Oximetry in Healthy Children"

DISCUSSION AND CONCLUSIONS: Smartphone-based pulse oximetry is not inferior to standard pulse oximetry in pediatric patients without hypoxia. [1]

However in this case you _are_ trying to test for hypoxia...

Another link answering the question "Should smartphone apps be used as oximeters":

CONCLUSIONS

It is not physically possible to measure SpO2 using current smartphone technology. The two published studies which assessed smartphone oximeter apps (Digidoc and Samsung) raise serious questions about the diagnostic accuracy. The Samsung app has been withdrawn, and the claim that oxygen saturation can be measured indirectly through “stress assessment” is false. [2]

[1] https://www.ncbi.nlm.nih.gov/pubmed/29215972

[2] https://www.cebm.net/covid-19/question-should-smartphone-app...

Many smartwatches have the hardware to measure oxygen saturation, though not all have it enabled. For example, all Apple Watches have hardware for it, and rumors (from before Covid was declared a pandemic) suggested that the next OS version would enable it. Depending on your worry level, you might want to wait to see what happens.

Also, this article mentions that people are subconsciously altering their breathing/heart rate when affected. If you already have a smart watch that is tracking your heart rate, you may be able to infer this condition by monitoring heart rate deviations from normal.

This is super-interesting. Could be extremely powerful along with contact tracing.

My mother has interstatial lung disease. We got her a Zacurate brand pulse oximeter. https://photos.app.goo.gl/MVkCa7GH9NuEbgbL6

Model 500E which was recently released then. It is rated at 2% +/- but their documentation says that their lab testing gives 1% +/-

Does not have memory as I did not need that so you will be able to spot check and not have, for example, overnight readings.

I have a OX-HC W512, which is certified for medical use. I wanted to make sure it would be reliable and correct.

In addition to having the alarm that you need for sports, it can also track heart rate and log your data. Later, you can then connect it via USB (or Bluetooth if you buy the upgrade) to do interesting analysis such as correlating your pulse and oxygen saturation with the route that you drove (mountain bicycling).

It's super nerdy, but a great toy for making your exercise feel like science.

thanks - the amount of a NYT article I can see before their subscribe banner would fit your summary, but unfortunately they don't use the lede to give me the entire story...

I think NYT articles are free during covid if you register and sign in. I don't have a sub and I am able to read NYT articles.

Disable Javascript, hit reload.

I usually have pretty good success hitting F5 to reload and then hitting Esc at just the right time before the ad stuff loads.

I read a thing a while ago (maybe on Reddit?) that I wish I hadn't read. It read that the body can detect low oxygen levels - causing you to want to breathe more. But CO (carbon monoxide) attaches to your red blood cells just like O does, meaning as far as your body is concerned, you're just fine in terms of oxygen levels. No "I am suffocating" panic reactions.

Get a carbon monoxide detector if you live or stay somewhere with an open flame. Infamously in my country, it's shitty gas powered caravan heaters that are often the problem. Garages with running vehicles as well.

> the body can detect low oxygen levels

No, it can’t. Your body uses a heuristic. It measures CO2 saturation. When that gets high, you get the urge to breathe.

This is why you never hyperventilate when diving. Your body will be oblivious right until you black out from oxygen deprivation. (I’ve seen it with a friend. They just “turned off” a few feet below the surface and began sinking. Fortunately, we were able to grab him.)

Carbon monoxide binds to haemoglobin stronger than oxygen. That reduces your blood’s oxygen-carrying capacity. You don’t notice because it does nothing to your blood CO2 levels.

Interesting article, but I'm not sure about the headline. The infection that's killing patients is the coronavirus.

I thought it was secondary infections that where a problem especially with older patients and those with pre-existing conditions like myself

Maybe, but that's not what the article is about.

I don't know if you're being pedantic, or what exactly.

The definition of infection on wikipedia is "An infection is the invasion of an organism's body tissues by disease-causing agents, their multiplication, and the reaction of host tissues to the infectious agents and the toxins they produce."

The infection killing patients is not "the coronavirus". The coronavirus is a particular kind of virus, specifically known as SARS-CoV-2. COVID-19 is, by definition "an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)". So to be pendantic, COVID-19 is the infection that is killing patients. The question of, by what mechanism the particular disease causing agents are producing the deadly reaction, is in fact is perfectly described by the headline.

Thanks for the explanation. As a layperson, the headline was very confusing to me, it gave me the impression that another pathogen was causing the pneumonia.

I guess I wasn't being pedantic enough. SARS-CoV-2 causing COVID-19 lung infections doesn't seem to be headline-worthy, let alone "silent".

It's "silent" because people weren't getting diagnosed properly before.

Why would you check for pneumonia in a guy that comes in presenting stab wounds and reports no difficulty breathing?

Only now because with increased testing and experience are doctors realizing that many people have a pneumonia that doesn't present like pneumonia.

If you diagnose the pneumonia early, what’s the treatment? The article doesn’t say what they do for people that can prevent needing to go on a ventilator.

Presumably, oxygen supplementation. The problem he's describing is patients injuring their lungs by straining (unconsciously) to breath harder as their oxygen levels, on atmospheric oxygen, fall.

From the article:

There are other things we can do as well to avoid immediately resorting to intubation and a ventilator. Patient positioning maneuvers (having patients lie on their stomach and sides) opens up the lower and posterior lungs most affected in Covid pneumonia. Oxygenation and positioning helped patients breathe easier and seemed to prevent progression of the disease in many cases. In a preliminary study by Dr. Caputo, this strategy helped keep three out of four patients with advanced Covid pneumonia from needing a ventilator in the first 24 hours.

A really stupid question - is oxygenating the blood externally a thing that is possible at all? Just like a dialysis machine filters the blood, is there a machine that can oxygenate the blood outside of the body?

Yes, but much more expensive and problematic than putting someone on a ventilator. The machine itself gets clogged with clotted blood so thinners are required to delay that breakdown.

And you thought the delirium caused by extended vent usage was exciting, wait till you read about pumphead syndrome!

Yes, it's called extracorporeal membrane oxygenation. The wiki article mentions that it was used on 3% of severe cases in China.

https://en.wikipedia.org/wiki/Extracorporeal_membrane_oxygen...

yes, it is called an ECMO machine and they're very rare and IIRC they're only really used during heart or lung transplant surgeries.

Pneumonia was called "The old mans' friend" as it killed people in their sleep without any pain.

Fitbit has sp02 sensor in it's watches. Could they detect Covid patients earlier?

https://www.youtube.com/watch?v=YRfwZcLeOm4

Not sure why this is downvoted, I founded it highly informative. Is there something I don't know about the channel?

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