0986: "Drinking Fountains"

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0986: "Drinking Fountains"

Postby jpk » Mon Dec 05, 2011 5:04 am UTC

Image

"I've always wondered whether you could drink slowly enough, and eliminate fast enough, that you just sort of peed continuously. But I'm afraid to try because I worry someone might call while I'm doing it and ask what I'm up to, and I won't be able to think of a lie."

Defintitely not a "get out of my head" moment.
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Re: 0986: "Drinking Fountains"

Postby alexriehl » Mon Dec 05, 2011 5:13 am UTC

Wow.

Just...

Wow.
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Re: 0986: "Drinking Fountains"

Postby michaelsaunders77 » Mon Dec 05, 2011 5:17 am UTC

The alt text is backwards. "drink FAST enough, and eliminate SLOWLY enough" would make more sense.
Although I'm pretty sure this isn't possible anyway. You would probably die of water intoxication before reaching a steady-state.
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Re: 0986: "Drinking Fountains"

Postby drainbramaged » Mon Dec 05, 2011 5:23 am UTC

"I've always wondered whether you could drink slowly enough, and eliminate fast enough, that you just sort of peed continuously. But I'm afraid to try because I worry someone might call while I'm doing it and ask what I'm up to, and I won't be able to think of a lie."


Get out of my head, Randall! I've been thinking about this for years!
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Re: 0986: "Drinking Fountains"

Postby WolfieMario » Mon Dec 05, 2011 5:27 am UTC

For a moment, I thought the text at the bottom was going to say "I avoid drinking fountains outside bathrooms because I'm afraid the 'water' is harvested in there.", or something to that effect. The random "Water" next to the bathroom door may have triggered me to think that, or it could just be me going to sleep at 3AM the past 3 days.


EDIT: May as well post this here too, since it's relevant to this post:
Image
(Originally I only posted it on the xkcd-sw thread)
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Re: 0986: "Drinking Fountains"

Postby Sir Lunch-a-lot » Mon Dec 05, 2011 5:28 am UTC

Perhaps we could run some personal experiments in which we log water input vs. water output and the time of each... see if we could find a meaningful relationship between those factors and from there try to determine the optimal water input rate. The trick would be eliminating variables such as the consumption of diuretics and water laden foods. Atmospheric humidity and physical exertion could also be factors. Also, urination flow rate (and control thereof?) would need to be tested... Well, maybe next time I'm unemployed, I'll see about collecting that data. Or not.
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Re: 0986: "Drinking Fountains"

Postby nash1429 » Mon Dec 05, 2011 5:29 am UTC

michaelsaunders77 wrote:The alt text is backwards. "drink FAST enough, and eliminate SLOWLY enough" would make more sense.
Although I'm pretty sure this isn't possible anyway. You would probably die of water intoxication before reaching a steady-state.


Yeah, I don't think the kidney would be able to process liquid fast enough to refill the bladder as you urinated, regardless of how much fluids you consumed. It's too bad though, I would be extremely entertained if I could get this to work.
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Re: 0986: "Drinking Fountains"

Postby Eebster the Great » Mon Dec 05, 2011 5:29 am UTC

michaelsaunders77 wrote:The alt text is backwards. "drink FAST enough, and eliminate SLOWLY enough" would make more sense.
Although I'm pretty sure this isn't possible anyway. You would probably die of water intoxication before reaching a steady-state.

No it wouldn't. The idea is to be drinking continuously and also pissing continuously, which means you could only be drinking a relatively small stream of water.

If instead of water you drank body-temperature buffered saline, this might indeed be possible. I'm not sure how long it would take before you got too exhausted and sore to continue.

E: The water would need to contain several different ions in about the right concentration as well as glucose (or sucrose or galactose). Balance is everything. Too much and the kidneys are overloaded; not enough and you die.
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Re: 0986: "Drinking Fountains"

Postby blowfishhootie » Mon Dec 05, 2011 5:32 am UTC

This is one of the stupidest - if not the single stupidest - comic ever posted here.

It's not realistic enough to be a worthwhile thinking point, and it's not absurd enough to be funny. Just ... totally pointless.
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Re: 0986: "Drinking Fountains"

Postby nash1429 » Mon Dec 05, 2011 5:33 am UTC

Eebster the Great wrote: The idea is to be drinking continuously and also pissing continuously, which means you could only be drinking a relatively small stream of water.


You would have to have *extremely* precise control over urination rate for that to work. To the point where it might not be possible to have such a low rate without stopping the flow completely.
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Re: 0986: "Drinking Fountains"

Postby solidxsnake » Mon Dec 05, 2011 5:41 am UTC

The bathroom on my floor of the dorm I live in has a drinking fountain INSIDE the bathroom. Go figure.
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Re: 0986: "Drinking Fountains"

Postby mania » Mon Dec 05, 2011 5:42 am UTC

michaelsaunders77 wrote:The alt text is backwards. "drink FAST enough, and eliminate SLOWLY enough" would make more sense.

No it isn't, and nash1429 explains why (despite agreeing with you):

nash1429 wrote:Yeah, I don't think the kidney would be able to process liquid fast enough to refill the bladder as you urinated, regardless of how much fluids you consumed.

Elimination involves a lot more more than the few moments you spend at the urinal... as nash (and the alt text) says, your kidney would need to process a lot faster for this to work.
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Re: 0986: "Drinking Fountains"

Postby Eebster the Great » Mon Dec 05, 2011 5:43 am UTC

nash1429 wrote:
Eebster the Great wrote: The idea is to be drinking continuously and also pissing continuously, which means you could only be drinking a relatively small stream of water.


You would have to have *extremely* precise control over urination rate for that to work. To the point where it might not be possible to have such a low rate without stopping the flow completely.

It would probably require a catheter, because yeah, your kidneys just aren't that strong.
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Re: 0986: "Drinking Fountains"

Postby michaelsaunders77 » Mon Dec 05, 2011 5:43 am UTC

mania wrote:
michaelsaunders77 wrote:The alt text is backwards. "drink FAST enough, and eliminate SLOWLY enough" would make more sense.

No it isn't, and nash1429 explains why (despite agreeing with you):

nash1429 wrote:Yeah, I don't think the kidney would be able to process liquid fast enough to refill the bladder as you urinated, regardless of how much fluids you consumed.

Elimination involves a lot more more than the few moments you spend at the urinal... as nash (and the alt text) says, your kidney would need to process a lot faster for this to work.


Well from some quick reseach...
20ml/second is average. Once you approach a steady state, I would assume that the differential in water retention with intake adjustments becomes negligible. So ignoring the constant amount we retain and use, we would need to drink 4.8 250-ml glasses every minute.

Healthy kidneys can only go through 1000ml/hr approximately, so you would die of water intoxication before you got anywhere close.

So you would definitely need to pee slower to avoid death, and you would definitely need to drink faster to get the required rate.
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Re: 0986: "Drinking Fountains"

Postby Kain » Mon Dec 05, 2011 6:01 am UTC

I have to say, I took issue with the alt text. If you are drinking constantly, how are you supposed to answer the phone?

Oh, solidxsnake, I would wager that the water fountain in the bathroom was put there by someone with memories of really bad nausea/food poisoning/diarrhea or what have you. You might be surprised just how fast the human body can dehydrate itself. (spending a night vomitting up everything in your stomach and then having to drink sink water because you are too weak to get to a water fountain in between retching is no fun, let me tell you).
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Re: 0986: "Drinking Fountains"

Postby faunablues » Mon Dec 05, 2011 6:04 am UTC

... except peeing faster wouldn't save your life from water intoxication. the kidney isn't going to filter faster just because your bladder is emptying faster; it does what it does.
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Re: 0986: "Drinking Fountains"

Postby faunablues » Mon Dec 05, 2011 6:08 am UTC

Eebster the Great wrote:
michaelsaunders77 wrote:The alt text is backwards. "drink FAST enough, and eliminate SLOWLY enough" would make more sense.
Although I'm pretty sure this isn't possible anyway. You would probably die of water intoxication before reaching a steady-state.

No it wouldn't. The idea is to be drinking continuously and also pissing continuously, which means you could only be drinking a relatively small stream of water.

If instead of water you drank body-temperature buffered saline, this might indeed be possible. I'm not sure how long it would take before you got too exhausted and sore to continue.

E: The water would need to contain several different ions in about the right concentration as well as glucose (or sucrose or galactose). Balance is everything. Too much and the kidneys are overloaded; not enough and you die.



Even with an isoosmolar solution to prevent water intoxication, it wouldn't prevent volume overload of the kidneys (or heart).

Happens to patients with too high of an IV rate. I'm not sure what would happen if you tried to ingest too much though (I'm not sure if you can actually volume overload that way); maybe you'd be too nauseous to keep the fluid down or, even better, have it go out the other end.

on another note
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Re: 0986: "Drinking Fountains"

Postby pbnjstowell » Mon Dec 05, 2011 6:10 am UTC

Try being pregnant.
Some days, I do feel like I'm peeing and drinking constantly.

Body needs more water -> drink more -> body processing more water -> pee more. And, repeat... for nine months.

I think that's about as close as I'll come to replicating the experiment.
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Re: 0986: "Drinking Fountains"

Postby Eutychus » Mon Dec 05, 2011 6:12 am UTC

WolfieMario wrote:The random "Water" next to the bathroom door
Yeah, about that... What's it doing there?
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Re: 0986: "Drinking Fountains"

Postby gormster » Mon Dec 05, 2011 6:22 am UTC

Eutychus wrote:
WolfieMario wrote:The random "Water" next to the bathroom door
Yeah, about that... What's it doing there?

Yeah, that's.. not in the right place? What the hell is that doing there?
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Re: 0986: "Drinking Fountains"

Postby xmillion » Mon Dec 05, 2011 6:29 am UTC

The other possible loop could be the water itself; where the water fountain gets water from the bathroom... which is what I thought of before I read the alt-text (and is more gross).
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Re: 0986: "Drinking Fountains"

Postby DrZaius » Mon Dec 05, 2011 6:31 am UTC

I once drank about 11 litres within 5 hours. It hurts. It really, really hurts.
After some time, the muscles controlling your bladder cramp which leaves you with the permanent feeling you need to pee as well as the permanent ability to pee, if only a few drops, since the bladder gets only refilled rather slowly. Also, you start losing the control, i.e. getting incontinent - which is just about as much fun as it sounds.
So to answer the original question: if you drink as much as you can for a long enough period - without destroying your kidneys - you will stay in the bathroom, if only for the constant fear, squeezing out the clear water dropwise. And I can't imagine it'd be nice to try it shortly before you go to sleep...
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Re: 0986: "Drinking Fountains"

Postby WolfieMario » Mon Dec 05, 2011 6:37 am UTC

gormster wrote:
Eutychus wrote:
WolfieMario wrote:The random "Water" next to the bathroom door
Yeah, about that... What's it doing there?

Yeah, that's.. not in the right place? What the hell is that doing there?

It's been an hour (?) and I still haven't figured out why it's there :roll:

xmillion wrote:The other possible loop could be the water itself; where the water fountain gets water from the bathroom... which is what I thought of before I read the alt-text (and is more gross).

Glad to see I'm not the only one who thought that at first too. Actually, I updated my post at the top; now it basically shows how I thought the strip would originally pan out.
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Re: 0986: "Drinking Fountains"

Postby phillipsjk » Mon Dec 05, 2011 7:07 am UTC

DrZaius wrote:I once drank about 11 litres within 5 hours. It hurts. It really, really hurts.
...


Contradicted me before I even posted.

I was going to say continuous flow is impossible (without a catheter) since your bladder is designed to slowly fill up, then release everything at once. When I am over-hydrated, the frequency is about every 20-30 minutes for me. Never tried 11L in 5 hours though.
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Re: 0986: "Drinking Fountains"

Postby Cdevon2 » Mon Dec 05, 2011 7:07 am UTC

Our Computing Science Centre, naturally, makes this loop as efficient as possible.

Our water fountains are inside our washrooms.
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Re: 0986: "Drinking Fountains"

Postby sherlip » Mon Dec 05, 2011 7:15 am UTC

So am I the only naive person on the planet that had no idea what kidneys do and thought water went through our internal pipes directly into the bladder?

I only understand some physics and chemistry.. and up to maybe Calc II.. and am a computer engineer major first-year freshman that has no code experience.. I feel special when I understand the comics, but when I don't, I come here and my brain is completely confused..
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Re: 0986: "Drinking Fountains"

Postby QRS » Mon Dec 05, 2011 7:34 am UTC

solidxsnake wrote:The bathroom on my floor of the dorm I live in has a drinking fountain INSIDE the bathroom. Go figure.


I know it sorta looks like a drinking fountain, but you're not really supposed to drink out of those things....
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Re: 0986: "Drinking Fountains"

Postby junes » Mon Dec 05, 2011 8:15 am UTC

Am I the only one concerned with how he seems to be going to the ladies-room?
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Re: 0986: "Drinking Fountains"

Postby pareidolon » Mon Dec 05, 2011 8:27 am UTC

Is it wrong that I never pass by a drinking fountain without taking a drink, meaning I always drink before AND after I pee?

xmillion wrote:The other possible loop could be the water itself; where the water fountain gets water from the bathroom... which is what I thought of before I read the alt-text (and is more gross).

Let's get this comic displayed on the door of the bathroom at the International Space Station, everyone!

DrZaius wrote:... the muscles controlling your bladder cramp which leaves you with the permanent feeling you need to pee as well as the permanent ability to pee, if only a few drops...

Wait, that's caused by bladder cramping? That's going to have me thinking for a while.

sherlip wrote:I only understand some physics and chemistry.. and up to maybe Calc II..

You're not welcome here sherlip. This is an academic forum only for people with advanced degrees in the sciences and mathematics. Can't you tell by the professional content being discussed?
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Re: 0986: "Drinking Fountains"

Postby Red Hal » Mon Dec 05, 2011 8:45 am UTC

pareidolon wrote:You're not welcome here sherlip. This is an academic forum only for people with advanced degrees in the sciences and mathematics. Can't you tell by the professional content being discussed?
Now you're just taking the piss.
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Re: 0986: "Drinking Fountains"

Postby Gye » Mon Dec 05, 2011 8:53 am UTC

DrZaius wrote:I once drank about 11 litres within 5 hours. It hurts. It really, really hurts.
After some time, the muscles controlling your bladder cramp which leaves you with the permanent feeling you need to pee as well as the permanent ability to pee, if only a few drops, since the bladder gets only refilled rather slowly. Also, you start losing the control, i.e. getting incontinent - which is just about as much fun as it sounds.
So to answer the original question: if you drink as much as you can for a long enough period - without destroying your kidneys - you will stay in the bathroom, if only for the constant fear, squeezing out the clear water dropwise. And I can't imagine it'd be nice to try it shortly before you go to sleep...

I got a similar effect drinking five litres of soda in six hours, along with one hell of a buzz. I don't think I want to know how much caffeine that was.
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Re: 0986: "Drinking Fountains"

Postby rhomboidal » Mon Dec 05, 2011 8:59 am UTC

Yes, improperly parameterized Fountain/Restroom loops are notoriously hazardous deathtraps.
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Re: 0986: "Drinking Fountains"

Postby DarsVaeda » Mon Dec 05, 2011 9:07 am UTC

You really should not try this at home kids!

First:
Indeed you die of water intoxication before you could reach the appropriate level.
This was tragically proven in Kalifornia, last year or so I guess, when a radio station held a contest.
The person who could drink most in the less time won a game console, or similar. A woman drank a lot water and died shortly after. Your body tries to compensate the mineral loss but fails. Symthoms are abdominal pain, headaches, ...
Source ie.:
http://www.msnbc.msn.com/id/16614865/ns/us_news-life/t/woman-dies-after-water-drinking-contest/

Second:
But in this case I suppose you will die from bacterial infection much faster than from the water intoxication.
Cause...a water fountain right next to the toilet? Seriously? Bahhhh! :?
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Re: 0986: "Drinking Fountains"

Postby Wooloomooloo » Mon Dec 05, 2011 9:38 am UTC

junes wrote:Am I the only one concerned with how he seems to be going to the ladies-room?

Nonsense! He's clearly going to the room for stick-men just as he should.

Also, as I think anyone familiar with catheters knows, we DO pee pretty much continuously, albeit slowly. So creating that loop is just a matter of rigging up a matched slow-dripping drinking system... :mrgreen:
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Re: 0986: "Drinking Fountains"

Postby songster » Mon Dec 05, 2011 10:22 am UTC

Questions raised by the alt text:

1) Can you drink fast enough so that you could pee continually at the same rate you normally pee, creating a continuous stream?
Answer: No. Typical flow rate is of the order of 10ml/sec, so the drinking part isn't difficult, but your kidneys couldn't keep up. In any case, you'd die by washing essential salts out of your system.

2) Can you pee slowly enough so that you can create a continuous stream while maintaining normal fluid intake / fluid balance?
Answer: Yes, but only if you're catheterised or incontinent, since you can't force your bladder sphincter to stay open at low bladder pressures. Drinking at a rate of ~10 microlitres per second would be tricky to arrange, but if you're catheterising one end, you may as well stick a drip or a feeding tube in the other. There's patients in hospitals all over the world doing variants of this right now.

3) Is there a happy medium somewhere between the two?
Answer: No. There's ~three orders of magnitude difference between the rate your kidneys generate urine, and the rate you release it while peeing, which is why you only need to spend ~1/1000 of your day peeing. Your kidneys might just be able to go up by one order of magnitude (assuming you drink physiological fluid to prevent wash-out), but you'll still be making urine 100 times too slow to pee it out normally - you'd have to be catheterised. If you're going to do that, then yeah it's possible (see 2), but (a) it's not really peeing and (b) why the hell would you want to?
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Re: 0986: "Drinking Fountains"

Postby VectorZero » Mon Dec 05, 2011 10:49 am UTC

Even a catheter wouldn't help, if you want truly continuous flow. The ureters pass urine from the kidney to the bladder as discrete boluses every 30 sec or so. Who'll take a bilateral nephrostomy for science?
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Re: 0986: "Drinking Fountains"

Postby AvatarIII » Mon Dec 05, 2011 10:53 am UTC

I've often wondered why animals need bladders and would it make more sense to just continually "seep" urine.

assuming a human should drink 2 litres of water a day, and therefore urinate approx 2 litres too, that's only 0.023ml.s-1, if we had evolved to urinate like this at the beginning, we would be used to it obviously, and it seems the existence of a bladder causes more trouble than it's worth, (urinary infections etc.)
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Re: 0986: "Drinking Fountains"

Postby swamp_ig » Mon Dec 05, 2011 11:29 am UTC

Urine output from the kidneys tops out at around 200ml per hour. That's only 3ml per min, or a couple of drops. In terms of fluid input, that equates to ~220ml in per hour (some you breath out). Short of putting in tubes and things, which gets done pretty regularly in hospital, or some rather unpleasant and irreversable urological surgery, I don't think it's possible.

Another issue is that the ureters deliver urine in drops, and they don't come through when the bladder pressure is up when urinating. This means even with the unpleasant surgery you'd still only drip, rather than stream, and without it you couldn't deliver more while you were pushing out what was already there.

I suspect the reason why animals have bladders is that a slow dribble means an easy pathway for infection to enter the body and track up to the kidneys, causing a kidney infection which are often deadly.
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Re: 0986: "Drinking Fountains"

Postby AvatarIII » Mon Dec 05, 2011 11:38 am UTC

swamp_ig wrote:Urine output from the kidneys tops out at around 200ml per hour. That's only 3ml per min, or a couple of drops. In terms of fluid input, that equates to ~220ml in per hour (some you breath out). Short of putting in tubes and things, which gets done pretty regularly in hospital, or some rather unpleasant and irreversible urological surgery, I don't think it's possible.

Another issue is that the ureters deliver urine in drops, and they don't come through when the bladder pressure is up when urinating. This means even with the unpleasant surgery you'd still only drip, rather than stream, and without it you couldn't deliver more while you were pushing out what was already there.

I suspect the reason why animals have bladders is that a slow dribble means an easy pathway for infection to enter the body and track up to the kidneys, causing a kidney infection which are often deadly.


that's true I suppose, although I would have thought the constant flow of urine out would help prevent bacteria getting up the urethra into the kidneys.

Also biology was always quite good with developing valves, a series of biological valve would possible prevent infections better than a bladder.
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Re: 0986: "Drinking Fountains"

Postby songster » Mon Dec 05, 2011 11:42 am UTC

AvatarIII wrote:that's true I suppose, although I would have thought the constant flow of urine out would help prevent bacteria getting up the urethra into the kidneys.

Also biology was always quite good with developing valves, a series of biological valve would possible prevent infections better than a bladder.


Um, the bladder sphincter IS a biological valve, that's the whole point. A constant flow is useless if it's slow enough for the bacteria to swim "upstream", or crawl along the mucosal surfaces. Solution: store the urine for a while and release it under higher pressure, to flush the pipes clean.
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