There are a handful of portable manual (handheld, hand-pump actuated) suction units on the market, and I've used what I believe are the two most popular designs. However, they left something to be desired, and alternative units don't seem to satisfy what I was looking for in a true backcountry-friendly suction device. To make a long story short, the market designs were some combination of the following:
I had seen, years ago, a portable suction device I liked, but I didn't know where to find it. It took going to paramedic school to learn that it was actually probably built out of an esophageal intubation detector (EID) and some tubing. So- I put one together myself, I think it's great, and hope that SAR EMS personnel might dig this page out of the web and do the same.
This 'design' is simple. It's most of the EID, with a tube stuck on the end. It is one-handed, light, robust, cheap, disposable, flexible, and can handle all types of aspirate. I played around with various concoctions to simulate various vomit/secretions and it seems to work nicely, although I have yet to use it in the field. I expect that the trade-off will be that it is (to use a medical term) "yuckier". But hey- when you need it, you need it, and if you're running around with this kind of gear you're likely not the type of person who will be incapacitated if the aspirate doesn't disappear into a hermetically sealed container.
How to make it
(image copied from boundtree website)
First, get the syringe body. Originally, I had thought to put it together with the ubiquitous (and cheaper) Toomey syringes. However, those syringes would not be one-handed operable, which is crucial for efficient suctioning (so you can open the mouth with the other hand, manipulate as necessary, etc). Anyways, you can get the correct syringe body online, marketed as an esophageal intubation detection device. I got mine from boundtree, for $5.77. Click here for link.. I also saw it from www.buyemp.com for $4.88, although I've never ordered from them. You could try experimenting with the bulb-style EID devices which might be easier to activate, but with less aspiration volume. Of small note is that different syringes feel different, and some are so stiff that some people will have trouble with them one-handed. Of course you won't know that until you splash out and get one in hand. (If your syringe is too stiff to operate easily, you can generally ease it up by removing the plunger and cutting away one of the rubber seals [note that the one pictured has three] to reduce the friction).
Then with a fine toothed saw (like a hacksaw blade (~$1), or a hacksaw, coping saw, dremel tool, etc) cut into the base of the ET fitting, so that it separates from the syringe body (you will see that the two are not actually bonded, but are joined with an o-ring seal and some flared plastic which needs to get removed to take the fitting off). You could probably do the same with a large drill bit, coming in from the end (in-line with the syringe) and drilling until the flared part of the device is cut away and the fitting will slide off the end. I didn't try this, but it would potentially be cleaner and easier. Leave as much of the nozzle of the syringe as possible. Trim any plastic burrs, and then find some catheter material to shove onto the tapered syringe nozzle.
I used clear vinyl tubing (3/8" internal diameter) from the hardware store. It's big enough to get a lot of chunky stuff out, but still fit most places. It's not sterile, but it's clean and suction devices don't need to be sterile. You could also use large uncuffed ET tube (ID 3/8" = 9.5mm). id go smaller, than larger, as a big tube is important for chunky vomitus but liquid secretions like blood are easier to suction with a smaller tube when you have such a limited suction device. Smaller (in the normal EMS range- 8mm, 7mm, for example) are reasonable. Cuffed tubes would work if you trim the cuff off with a razor blade, although it won't be as pretty. Cuffed ET tubes are under 2 bucks online. Uncuffed tubes are hard to find in larger sizes, but are also inexpensive.
Consider cutting the catheter long, so it can be cut down a cm or two for a new tight fit at the nozzle, or so you can cut the Murphy eye off if you need more suction at the distal tip of the catheter, or if it needs to be shorter (and therefore stiffer) for some reason. Cutting it shorter only takes a second on scene. Just be careful because a long catheter can go deeper and you might poke or damage something rooting around down there if you aren't familiar with deep suctioning.
I cut the distal tip of the catheter tip at an angle, and punched a hole in the long side of the distal bevel for a DIY murphy eye. I don't know if that's really useful in a suction device that won't do continuous suction, but my catheter is long so I can snip it off later if it isn't working well. I carefully shaped and beveled the edges of the tip of the cuff with a razor blade, but it bears mentioning that the tubing itself is soft so this is probably unnecessary. Using an ET tube (with nice rounded factory edges) would take away this unknown.
Resist doing what I did, and don't cut the syringe nozzle any shorter. The limiting factor in ease of withdrawing plunger is plunger seal friction. Leaving the narrower tip of the nozzle on allows you to take the big catheter off and force on a oxygen tube (ie: from the proximal end of a NRB setup) or a standard gastric tube or suction catheter or foley. For a caveman-like NG/OG (you'd have to be desperate, and you would have to keep taking the syringe on and off if you wanted to keep suctioning) you could use the tubing from an oxygen delivery device (cannula, facemask, etc), or you could cut these short as a thinner catheter that will better fit tiny mouths or nasal passages or for deeper/tracheal suctioning.
All that said, it definitely bears mentioning that if you want the ultimate in flexibility with your minimalist wilderness ALS pack, you might just buy the EID and use it as-is. Pop on whatever ET tube to the ready-to-use ET-size adapter and suction away. That way you can use the EID as it was intended as well, and have ready-to-go suction catheters of various sizes. If you want deep suction you could pull the ET tube off the adapter of a peds ET tube and ram that into thinner catheters. Easy. Flexible.
Move plunger just before using, because syringes magically 'stick' if they've been left sitting for a while, and it's hard to break it free the first time one-handed. Depress plunger. Stick it in whatever needs suctioning. pull out plunger with thumb. Its one handed, so you can use other hand to open mouth, etc. Once plunger is withdrawn, remove from mouth and squirt aspirate somewhere else. Use is similar to a neonate suction bulb, but with a 40cc-per-stroke capacity, and able to handle 'textured' aspirate.
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