# lung capacity **URL:** \ **Category:** Factual Questions\ **Created:** [March 29, 2000, 2:01am UTC](https://boards.straightdope.com/t/lung-capacity/9419 "2000-03-29T02:01:00Z")\ **Posts on this page:** 16\ **Page:** 1
**Author:** ![Jeannie](https://avatars.discourse-cdn.com/v4/letter/j/e480ec/32.png) [@Jeannie](https://boards.straightdope.com/u/Jeannie)\ **Post date:** [March 29, 2000, 2:01am UTC](https://boards.straightdope.com/t/lung-capacity/9419/1 "2000-03-29T02:01:00Z")
Okay, so my mom had to go into the hospital to have some fluid removed from her left lung. (It’s a somewhat long story). Anyway, they took out a quart of fluid. That sounds like an awful lot to me. So, how much would the lung hold? BTW, she’s awake and fine and the doc says it’s probably no big deal. ---
**Author:** ![Ursa\_Major](https://avatars.discourse-cdn.com/v4/letter/u/a88e57/32.png) [@Ursa\_Major](https://boards.straightdope.com/u/Ursa_Major)\ **Post date:** [March 29, 2000, 2:28am UTC](https://boards.straightdope.com/t/lung-capacity/9419/2 "2000-03-29T02:28:00Z")
The max for both lungs is about 4 quarts, however, during normal breathing you only take in about half a quart at a time. ---
**Author:** ![kinoons](https://avatars.discourse-cdn.com/v4/letter/k/a698b9/32.png) [@kinoons](https://boards.straightdope.com/u/kinoons)\ **Post date:** [March 29, 2000, 2:53am UTC](https://boards.straightdope.com/t/lung-capacity/9419/3 "2000-03-29T02:53:00Z")
actally, total lung capacity is 6000ml it is broken down to the following Inspiratory reserve volume (amount you can take in if you breath in all you can) is 3100ml tital volume (air you move during normal ventlation) is about 500ml expratory reserve volume (amount of air you can forceably exhale) is about 1200ml and residual volume (air that stays in the lungs) is about 1200ml total equals about 6000ml, or 6 liters * * * Kinooning it up for 20 years and counting ---
**Author:** ![SingleDad](https://avatars.discourse-cdn.com/v4/letter/s/9e8a1a/32.png) [@SingleDad](https://boards.straightdope.com/u/SingleDad)\ **Post date:** [March 29, 2000, 2:57am UTC](https://boards.straightdope.com/t/lung-capacity/9419/4 "2000-03-29T02:57:00Z")
I’m not following this. If you can exhale 1200ml and there’s 1200ml left, that’s a total of 2400ml. So how can you breath in 3100ml? ---
**Author:** ![kinoons](https://avatars.discourse-cdn.com/v4/letter/k/a698b9/32.png) [@kinoons](https://boards.straightdope.com/u/kinoons)\ **Post date:** [March 29, 2000, 3:03am UTC](https://boards.straightdope.com/t/lung-capacity/9419/5 "2000-03-29T03:03:00Z")
okay, here we go. during normal ventlation your lung volume hovers around 2500-3000ml (2500 when you complete exhaliation, 3000 when you complete inhaliation). Now, the inspratory reserve volume is what you can inhale forceably beyond 3000ml, and that is up to 6000 ml. The expiratory reserve volume is what you can forceably exhale beyone the 2500 that you stop at when normally breathing, down to the residual air that remains in the lungs so the math says IRV (3000) + TV (500) + ERV (1200) + RV (1200) = about 6000ml, or 6 liters The numbers above are approxmates, and may vary depending on a persons size * * * Kinooning it up for 20 years and counting ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [March 29, 2000, 3:05am UTC](https://boards.straightdope.com/t/lung-capacity/9419/6 "2000-03-29T03:05:00Z")
A point of clarification. The fluid that was removed was, no doubt, taken from a so-called _pleural effusion_. This is a collection of fluid that actually resides _outside_ the lung (between the lung and inside of the chest wall). This potential space between the lung and the chest wall is much greater than the volume of the underlying lung. So, it’s not too impressive to have had a quart or more accumulate. A similar problem occurs in the belly, between the outside of the guts and the inside of the abdominal wall. It’s called ascites. There can easily be 10 to 25 litres of such _ascitic fluid_. That’s over twenty to fifty pounds for you non-SI unit types! ---
**Author:** ![kinoons](https://avatars.discourse-cdn.com/v4/letter/k/a698b9/32.png) [@kinoons](https://boards.straightdope.com/u/kinoons)\ **Post date:** [March 29, 2000, 3:09am UTC](https://boards.straightdope.com/t/lung-capacity/9419/7 "2000-03-29T03:09:00Z")
[http://www.unm.edu/~jimmy/lung\_volumes.jpg](http://www.unm.edu/~jimmy/lung_volumes.jpg) the above link goes to a graph that demonstrates the volume of the lungs, explains their volumes much better that I seem to have been able to. As for the fluid being removed from around the lung, that is likely. It is also possible for the fluid to accumulate into the lung itself. It all depends on what is causing the accumulation and where it is going on. TO say it was undoubtably removed from the plural linging and the sac it forms around the lungs is being too general. * * * Kinooning it up for 20 years and counting ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [March 29, 2000, 3:44am UTC](https://boards.straightdope.com/t/lung-capacity/9419/8 "2000-03-29T03:44:00Z")
Actually, I can guarantee that the fluid was removed from _outside_ the lung. It was taken from a pleural effusion. I am not being too general. Fluid _within_ the lung (pulmonary edema) is diffuse and is not contained in a drainable sac or space. It cannot be mechanically drained. It can be mobilzed by medications such as diuretics. Next, we could talk about pericardial effusions (fluid around the heart), but I’d probably faint just thinking about the last one I drained. The patient did. I thought she was dead. ---
**Author:** ![kinoons](https://avatars.discourse-cdn.com/v4/letter/k/a698b9/32.png) [@kinoons](https://boards.straightdope.com/u/kinoons)\ **Post date:** [March 29, 2000, 3:55am UTC](https://boards.straightdope.com/t/lung-capacity/9419/9 "2000-03-29T03:55:00Z")
> [@](#): > > Originally posted by KarlGauss: > \*\*Actually, I can guarantee that the fluid was removed from _outside_ the lung. It was taken from a pleural effusion. I am not being too general. > > Fluid _within_ the lung (pulmonary edema) is diffuse and is not contained in a drainable sac or space. It cannot be mechanically drained. It can be mobilzed by medications such as diuretics. > > Next, we could talk about pericardial effusions (fluid around the heart), but I’d probably faint just thinking about the last one I drained. The patient did. I thought she was dead.\*\* Would you like to talk about caradic tampanod? It does suck when you have blood filling the caradic sac, preventing the heart from fully expanding to allow for the maximun input of blood into the heart. The narrowing of the BP is a good sign for this. I got my last patient who suffered from this to the hospital in time to save them. Now then you can actually suction the lungs to remove fluid from them, I’ve seen it done in the ER. It is a drastic measure, and is not commonly done. Again, to flat out say that the fluid was not removed from the lung is a generalization. It was most likely removed from the plural sac around the lung, but that would not be a deffenite. * * * Kinooning it up for 20 years and counting ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [March 29, 2000, 4:00am UTC](https://boards.straightdope.com/t/lung-capacity/9419/10 "2000-03-29T04:00:00Z")
Show me a reference attesting to the mechanical drainage of intraparenychmal lung fluid and I’ll drink the next sample that’s taken. ---
**Author:** ![kinoons](https://avatars.discourse-cdn.com/v4/letter/k/a698b9/32.png) [@kinoons](https://boards.straightdope.com/u/kinoons)\ **Post date:** [March 29, 2000, 4:25am UTC](https://boards.straightdope.com/t/lung-capacity/9419/11 "2000-03-29T04:25:00Z")
I shall swallow some pride to say that I do not have a refrence directly at hand. I can only say that I would have swore I had seen it done once in a patient I had dropped off, but that could have simply been suctioning of the trachea. Beyond that I was told that it was possible by an instructor. I shall speak with the resources I have at UNM medical center and will have to get back to you on that. * * * Kinooning it up for 20 years and counting ---
**Author:** ![Jinx](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@Jinx](https://boards.straightdope.com/u/Jinx)\ **Post date:** [March 29, 2000, 8:39pm UTC](https://boards.straightdope.com/t/lung-capacity/9419/12 "2000-03-29T20:39:00Z")
> [@](#): > > Originally posted by kinoons: > **tital volume (air you move during normal ventlation) is about 500ml** Correction! The term is “tidal”! (Was that a Freudian slip?) * * * “They’re coming to take me away ha-ha, ho-ho, hee-hee, to the funny farm where life is beautiful all the time… :)” - Napoleon IV ---
**Author:** ![system](https://global.discourse-cdn.com/straightdope/original/2X/e/e489c3b7d8fce19c4b355dd4fc3f88cc39c34b87.png) [@system](https://boards.straightdope.com/u/system)\ **Post date:** [March 30, 2000, 1:07am UTC](https://boards.straightdope.com/t/lung-capacity/9419/13 "2000-03-30T01:07:00Z")
::This is a test post. Please ignore it:: ::If you see multiposts above, please ignore them, too. I’ll clean them up:: Note to **Jinx** : You did. I saw it. I made them and the comment go bye-bye. Just call me Mr. Clean. [Note: This message has been edited by manhattan] ---
**Author:** ![kinoons](https://avatars.discourse-cdn.com/v4/letter/k/a698b9/32.png) [@kinoons](https://boards.straightdope.com/u/kinoons)\ **Post date:** [March 30, 2000, 1:24am UTC](https://boards.straightdope.com/t/lung-capacity/9419/14 "2000-03-30T01:24:00Z")
Ahh, good lord, what the heck was I thinking as I was typing. Of course it is tidal volume…good lord \ * * * Kinooning it up for 20 years and counting ---
**Author:** ![Jinx](https://avatars.discourse-cdn.com/v4/letter/j/c6cbf5/32.png) [@Jinx](https://boards.straightdope.com/u/Jinx)\ **Post date:** [March 31, 2000, 6:02am UTC](https://boards.straightdope.com/t/lung-capacity/9419/15 "2000-03-31T06:02:00Z")
If it is any help to the arguement over if it’s possible to drain fluid by mechanical mean from the lung interior, I found a reference which uses a (external) pump to drain fluid from the lungs usig a tube inserted through the lung wall. But, this reference…although legit…does not mean the method actually is successful! ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [March 30, 2000, 8:53pm UTC](https://boards.straightdope.com/t/lung-capacity/9419/16 "2000-03-30T20:53:00Z")
The tube inserted through the chest wall which drains fluid “from the lungs” is almost certainly draining pleural fluid, i.e. fluid which is outside the lung but inside the chest wall. The apparatus that you describe cetainly sounds like that’s what it’s doing. One reason why I can’t believe it’s possible to drain fluid from within the lung via an external tube is that, essentially, such a tube would ultimately be in series with your windpipe, i.e. it would suck air down your windpipe into itself (a tube between the outside of your lung and the inside of your chest wall, would not communicate in this way). Moreover, fluid in the lungs is not localized and therefore does not lend itself to be mechanically drained (an abscess does, but that’s not what we’re talking about).