Breathless Journalism

from https://old.reddit.com/r/pics/comments/foo7qm/italian_guy_designed_a_3d_printable_valve_to_turn/


[–]Vandimal88 184 points  
It looks like it would essentially work as non-invasive positive airway pressure similar to CPAP or BIPAP. That still uses positive pressure to force air into the lungs but without a tube that goes down the trachea past the vocal cords. There are many limitations on this kind of ventilation compared to intubation. With intubated patients you can control parameters such as positive end expiratory pressure (PEEP) which helps stent open the alveoli when they fill with fluid (acute respiratory distress syndrome) which is a common complication from COVID-19. You can’t reliably control all of these parameters with non-invasive positive airway pressure because it relies on the patient to be able to take their own breaths. They can tire out or if their mental status deteriorates and they are not able to maintain their airway (keeping mouth open, clearing secretions) they will aspirate. Intubation basically takes over and sets a respiratory rate while also protecting the lungs from aspirated materials from above. This will not replace the need for ventilators.
[–]bion93 37 points  
In fact it’s a CPAP.
[–]debateg 10 points  
I agree. It definitely doesn't look like a definitive airway at all. I'm not aware that there's a shortage of ET tubes (as of 25th March 2020) that would necessitate using BiPAP or CPAP instead. There's certainly a shortage of ventilators. Unless things have changed in the last few years, I learned that BiPAP and CPAP should not be used in place to intubation if possible. At best, it can be used as a bridge if you need to buy some time or think you can fix the problem (e.g. diurese) which I've had some success with. The classical teaching is that if you are thinking about using it as a bridge, you may as well just intubate. From what I've read about COVID19, early intubation really should be done because as people decompensate, they crash really quickly. Using this mask or high flow oxygen will probably constantly generate aerosols which may be contained while wearing the mask, but I imagine will spread everywhere when you take it off. Intubating will too but only during the procedure. With a massive shortage of PPE, it seems that you want to minimize generation of aerosols because you have to use an N95/PAPR and pretty much shut down the room for 3+ hours. In a place where BiPAP masks are in short supply, I see this as being useful. But for the COVID pandemic, I just don't understand what problem this solves.
[–]Vandimal88 7 points  
Absolutely. Coming off a night shift with three rapids called it’s interesting to see how these patients are like bombs with long fuses. They’ll be chugging along on 2-3 liters of oxygen for 3-4 days and all of a sudden decompensate and have to go to the icu for intubation. Doesn’t really lend itself to having a window for using BIPAP.
[–]not-a-shark 2 points  
This really clarified the issue for me. Thank you.
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[–]coffeemug613 161 points  
It’s probably Bipap...which no matter how hard you try is going to have small gaps in the seal.
Aerosolizing will still be an issue.
Can you imagine having to wear this mask as a patient? In reality, they are going to want a break, take it on and off.
[–]danntroll 16 points  
That’s true, it could be BIPAP, the attachments make it look that is more accurate than just for supplemental oxygen.
[–]ryanhallows 58 points  
This reduces the amount of exposure to anything coming out of their faces tho and healthcare workers are desperate for that. Especially since the majority are armed only with masks (and some don’t even have that)
[–]serengeti_yeti 11 points  
Not really though. The issue is that BiPAP and CPAP are considered to be aerosol-generating procedures-- as in, they are procedures that may stimulate coughing and the patient's production of aerosols and/or droplets. When you generate aerosols in an infected patient you actually increase infectivity and exposure risk to all of those around the patient. Our emergency department has issued a strict "no BiPAP/CPAP" policy during the current pandemic due to the increased risk to all healthcare workers and family members.
[–]pause_and_consider 28 points  
In theory...kinda maybe a little? In practicality, no way. One of the big issues with BIPAP/CPAP in general is that it’s wildly uncomfortable and creates a ton of anxiety in most patients. Put it on someone that’s never worn it before, and there’s about a 0% chance they don’t rip it off at some point. Then you have a ton of aerosolized particles flying everywhere which is exactly what we don’t want.
This just adds that much more anxiety since you have the pressure of a BIPAP but it’s blowing on your entire face now. This would be a level of uncomfortable bordering on downright painful. Unless it’s not BIPAP and just a kooky looking nonrebreather/nebulizer or something.
Basically this better be an extreeeemely last ditch bridge measure while they get more supplies because it’s an awful, awful design.
Source: ER nurse who’s also been a patient on BIPAP
[–]ryanhallows 7 points  
I mean we have nurses sewing their own masks we're getting pretty desperate
[–]pause_and_consider 15 points  
What I mean is, this is downright awful for the patient. I’ve been on every (yes I mean every) level of respiratory support device from my own ARDS adventure and past a nasal cannula they’re all pretty miserable. Anything involving a mask is claustrophobic and uncomfortable and anything involving pressure gets very painful very quickly. I can’t imagine having that pressure on my whole face for more than a few minutes without going nuts. BIPAP requires a lot of pressure.
As for staff, that’s a different thing. My hospital basically (aside from some very extreme/specific scenarios) put a stop to respiratory therapies that blow particles. That means nebulizers, BIPAP, CPAP, and high flow nasal cannulas among some other niche therapies (nebulized TXA, epi, etc).
I’m having trouble thinking of a scenario where this mask actually benefits anyone except the people getting internet points from posting it.

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