Creating a Biohazard Space for COVID19 Intubation: A covid intubation tent / box

Much like a biohazard hood; 2 principles are used in this example

• negative pressure (pulling bad particles away from you)
• directionality shielding (a clear shield protects your face while you work; and all other 3 sides are shielded)

In the most extreme situations a complete seal is formed. This doesn't work for emergent airways; we need something we can set on top of a patient in seconds; and get to work. It needs to be cheap, lightweight, and idiot proof.  We need visibility. We need to protect everyone in the room; and give the intubator the best visible window and flexibility to work. 

Here is model one; the fastest and cheapest solution I could build in 5 minutes with stuff from a hardware store:

• set of 6x 1/2" PVC pipes; cut to 23.5" length [$4]
• 4x 3-way and curved standard fittings at junctions [$4]
• 72x72" clear vinlyl sheet (AKA a shower curtain) [retail $2]

 I tried working under the slack of the front pieces; works; but particles preferentially go out into the user.

VIDEO SHOWING ASSEMBLY/USE/DISASSEMBLY OF VERSION 1

I have updated the C clips to be easier to snap on and off. And I have decided against the silicone arm holes; rather cutting flaps as shown below. You can also perforate the plastic and then punch through when needed.

I've also stopped putting clips over the top; as its nice to have slack in the vertical direction during use. Watching a few other ICU and ED docs use it that was the most common wall struck during intubations (on an intentionally difficult maniquin).

Also, I bought a new/clean shower curtain and visability is MUCH improved (water stains from the old curtain made it blurry in the first version.  Target sells this one for $2

 Today I experimented with overhand arms; 6" long on the top braces; adds neglicible weight; but changes how the sheet folds over. The main benefit is that you have more working room; no need for the sheet to go down to the mid-chest; in fact it enables chest compressions this way to shorten the arms along the pt's sides.

It also makes it easier for a 2nd or 3rd user to enter from the side. I cut quick circles and X's with a blade; took seconds, and works just as well as a careful loop. In a pinch it lets a second user in. 

I think it's worth adding the overhang; since the roof is what more user hit; and just choke up on the clips in the back of the unit. Make it more of a trapazoid.

Went and got more supplies; as we are gonna roll this out in our system at each site. I found cheaper parts too. Junctions are $0.65 and 10 feet PVC pipes were $1.69 for a 10 foot slat; I also got a PVC cutter for $15; worth every penny, cuts em like butter. I made 6 more units in 30 minutes; and got buckets to hold/clean em.

My buddy Jimmy found a good C clamp alternative; so no 3d printer needed. Its in the same aisle as the PVC pipes

I've used the tent twice so far; the major issues are getting tools in and out of the space; a video scope with a short cable is better fed through the side rather than under the tent edge (and make sure the railing is down or it will get caught). The second time I cut a hole in the sides (now I use X cuts rather than circles) to pass equipment though the sides or front. Went smoother the second time. 

A recent particle test by my buddy Jimmy at UC Davis shows how much gets blocked by the tent; let this be motivation to wear good PPE as you aeosolize during intubation

Files below

C-clip v3.27.20

https://drive.google.com/file/d/1wkQXHUYAqahx7baBKXvkhJEC0ibHXlYC/view?usp=sharing

C-Clip v3.24.20

https://drive.google.com/file/d/1DScsLzi-cxOXCx1ATNbP1d9A3DSfjpb0/view?usp=sharing

Mold ArmHole v3.24.20

https://drive.google.com/file/d/1cvv0qyzO6_QEono29neNoHUcsyHkLhVr/view?usp=sharing

 If you want to use it as a negative pressure space; you can hook up suction from the wall in series but this may prove somewhat dangerous.  It would be less dangerous to simply use a PAPR backwards (the mechanical base in the tent) to draw air from the space and send clean filtered air out into the room. I see a lot of people using my wall suction idea: using a shop vac pulling through a filter; or wall suction, or suctioning through the PVC pipe itself. but I would strongely argue against this method as it is hard to guarenttee a seal from the fitting merger point to the wall suction and there is a large chance for leak; anything pressurized or vacuum creation is an opportunity for more aerosolization. through small cracks or connections. A mixed port is needed if you want to use wall suction; as a single line is not enough draw.

This concept was used in practice; and has been used at over 2 dozen sites so far.

Published work describing its use with a cleaner vacuum port is described below:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7228800/#!po=30.0000

***DISCLAIMER***

WARNING: Your Design Medical and it’s Owner Justin Henneman make no guarantee whatsoever that these devices will function perfectly (or even at all). These items were developed because people are dying & the health of our nation including our medical personal are at stake. Everything you do is at your own peril (welcome to life); but doing nothing to help is probably just as risky. Try not to sue me for helping once the dust settles; at least I can sleep at night knowing I tried.