Breathing for someone else underwater

The person giving breath is going to get dizzy as he has to constantly go up for air, take as much air in as he can and then go back under and repeat. He can actually hyperventilate from this process.

The person receiving the air is also going to swallow water if the connection is not just right. This will cause them to cough and lose air and take in more water.

If possible, if the water is not too deep, I suggest having the character who is not trapped find a tube of some sort to use like a straw. This way his friend can breath while he trys to free his friend or call for help.

Straws are hard, because over a certain length [as noted above; this is clarification only], the air in the straw itself will just be rebreathed. Suck in what you can (fresh), breath out what you must into the straw, and if the straw is long enough, that air breathed out never reaches the top and is just waiting to be sucked back in, over and over.

Re: the original post, a certain episode of Due South that sparked a metric ton of fan fiction comes to mind.

I have a scene like this in my story, but the one who isn't trapped only has to do it twice before the trapped one breaks free. I don't think this works other than for a very short term.

As for the tube/straw, plug it with the tongue and expel the air into the water.

Too narrow, though, and the straw can't keep up with demand.

robjvargas said:

Too narrow, though, and the straw can't keep up with demand.

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Too thick and the breather can't get enough oxygen. If the volume of the tube is similar or greater than the breather's lung capacity they'll end up breathing sour air quite quickly. You're breathing in the air you just breathed out, just like with a plastic bag.

Drachen Jager said:

Too thick and the breather can't get enough oxygen. If the volume of the tube is similar or greater than the breather's lung capacity they'll end up breathing sour air quite quickly. You're breathing in the air you just breathed out, just like with a plastic bag.

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Not thick or thin. Wide or narrow. A drinking straw, even if long enough to get air, doesn't have the flow capacity to keep up with the body's oxygen needs. A 1/2-inch plastic tube can.

As for breathing stale air, since stealth isn't a requirement, there's no reason that the trapped person (per the OP's scenario) couldn't or wouldn't exhale directly into the water. Use the tube only to inhale.

robjvargas said:

As for breathing stale air, since stealth isn't a requirement, there's no reason that the trapped person (per the OP's scenario) couldn't or wouldn't exhale directly into the water. Use the tube only to inhale.

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True enough. The times I have been trapped underwater, I wouldn't have had the presence of mind. At least, I don't think so. I mean, I would like to have that presence of mind, but as I recall my mind was off screaming somewhere in my hairy ancestors' squat-portioned brain.

evila_elf, here is the scene. The blond guy is a Chicago cop, and the one in red is a Candian mountie. The latter first came to Chicago on the trail of the killers of his father, and for reasons that don't need exploring at this juncture he remained, attached as liaison with the Canadian Consulate. (Heh.) An then there's his deaf half-wolf Diefenbaker, as well as the ghost of his father.

It is a tricked-out blend of surrealism, contrarealism, and pararealism, and you can't watch it without reading truepenny's reviews either alongside or at least at some point after. That link is her initial summary, and although it contains spoilers, you are pretty safe up till the following:

And one of the things the pilot proves is that actually, his strategy works very well.

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Before that the only spoiled parts are from the first 10-15 minutes of the pilot.

Will a plastic bag help? Still tedious but I imagine it would beat mouth-to-mouth transfer of air.

Now that would entirely depend on authorial intentions.

*eyebrow waggle*

Twenty minutes of having the un-trapped character give the trapped character fresh lungs full of air is going to cause the un-trapped character to hyperventilate and maybe pass out. This is why CPR people switch every three minutes or so when doing CPR. It is very draining to the person performing the breath in, breath out.

Forget the f-in straw people, it was just an example. You could use a garden hose or other similar tube like object. . The person doing the rescue pushes the air down the hose from up above. The person below expels the used air into the water while holding the hose/tube/pipe, whatever closed, and then sucks from the hose/tube/pipe, whatever when needed.

Come on people, use your imaginations. I remember watching a movie where a guy was sucking air from a car tire. Talk about stale air...

Maybe I shouldnt jump in here, but as someone who has both scuba'd and snorkeled, I couldn't imagine breathing In a tube, pluging it to exhale, then breathing in via the tube, Under Duress, and not getting lots of water in my lungs(slowly or all at once). You NEED your exhale to clear the pipe, and if the pipe is much longer than a snorkel, and youre doing this for more than 5 minutes, forget it.

For a previous discussion on the issue: Saving a drowning person...

Best of luck,

Jim Clark-Dawe

I thought this was familiar

thothguard51 said:

Forget the f-in straw people, it was just an example. You could use a garden hose or other similar tube like object. . The person doing the rescue pushes the air down the hose from up above. The person below expels the used air into the water while holding the hose/tube/pipe, whatever closed, and then sucks from the hose/tube/pipe, whatever when needed.

Come on people, use your imaginations. I remember watching a movie where a guy was sucking air from a car tire. Talk about stale air...

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As long as the drawn-in air has sufficient oxygen content, then staleness is likely the least of the concerns during the situation the OP proposed.

And, now that I've rethought it, I know I brought up exhaling, but doesn't the trapped person have a nose that exhales, or that can?

Sorry, Mr Myagi. The guy's going to have to breathe backwards.

Just a thought, rather than plugging the hose and getting water in it.

There is one thing I haven't seen mentioned. The reason that snorkels (or straws or anything else) aren't more than about 14-16 inches is because if they are longer than that the water pressure would prevent someone from inflating their lungs.

Just have your guy hold his breath. If the water is very cold then he'll last longer than in warm water and can hopefully be revived if he passes out. There are lots of cases of cold water drowning victims being revived after a *long* time in the water if they are very cold. Apparently you're not dead until you're "warm and dead".

I hope this helps