MedCram - Medical Lectures Explained CLEARLY
3 HN recommenders · recommended in 5 months, 2020
11:05 · 4.7M views · Jan 29, 2020
A pulmonologist and critical care physician explains how COVID-19 can lead to pneumonia and acute respiratory distress syndrome. He covers evidence-based ARDS treatments such as low tidal volume ventilation.
In early 2020 HN commenters linked it as a clear explanation of how the virus kills through lung failure and why ventilator choices matter, notably in ventilator design threads.
6 comments from Hacker News
I really like this as DIY - I also found this video this video - explaining how the virus eventually kills by causing failure of the lungs. After explaining the functional parts he goes on to explain what seem like some interesting things to consider when designing a ventilator with respect to how they were used during the SARS outbreak. e.g. tidal forces causing iteration and more inflammation, which then cuts off more air flow. So thinking about how you maintain a constant air pressure instead of more pushing force... at least the explanation made sense intuitively but I'm not a doctor and don't know if this video or your Ventilator are safe - but I do like the DIY aspect of it and figure thinking about or sharing ideas can't be bad...
Thanks. I'm not a doctor so I could be wrong (and happy to be corrected) but from my understanding the problem with those techniques in this situation is that they are for clearing mucus from the lungs (in the bronchi and broncioles) not from alveoli, because mucus isn't the type of fluid in the alveoli. Hence, they'd have little effect. This video[1] goes into what happens when you have ARDS caused COVID and how it will be treated. It shows why machines like CPAP aren't appropriate too. [1] this video How Coronavirus Kills: Acute Respiratory Distress Syndrome (ARDS) & COVID-19 Treatment
One of the main causes of death of the new coronavirus seems to be Acute Respiratory Distress Syndrome (ARDS). This can be treated fairly effectively with ventilation, but such treatment would obviously require a bed, ventilation system, and attentive nurses, at the very least. It's easy to imagine how these requirements may currently not be met for all patients with ARDS symptoms in Wuhan. For more info on ARDS and treatment in the context of the current pandemic, see this informative explanation: this video
Someone linked me to this a few days back: this video It explains how they pressurize the lungs to try to keep the alveoli open and why that's very problematic, even when it is only short term. It is so problematic, they sedate people on ventilators so they won't pull the tubing out. It sounds just really gruesome and like a brute force method that can't help but cause serious problems for delicate tissues if you use it for more than a fairly short period of time, which is the norm but is not how it is being used for Coronavirus cases. Oxygen delivery is a complicated thing and I think taking a mechanical approach when mechanics may not be the actual problem is likely misguided.
For coronavirus, it doesn't necessarily have to be the death rate as of this moment that should cause worry. Coronavirus can cause ARDS, described here: this video Treating ARDS in a handful of cases isn't so bad. It's treating ARDS in hundreds of thousands of people that's very very bad. Hospitals can quickly become full and hospitals also rely on supply chains for materials, which would also become overwhelmed. I'm not saying panic is the right thing to do, because it isn't, but what I am saying is that the quarantines aren't excessive and there's a reason why governments are paying attention.