robind
Well-Known Member
has/does anybody used saline enemas in a rehydration situation? If so why cant sea water be ingested in this manner for survival purposes. Just a thought
Rob. and what amounts etc
Rob. and what amounts etc
any doctors out there? a question
- Thread starter robind
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andy_wilson
Well-Known Member
osmosis
The average salt content of body fluid is too saline, and cellular fluid migrates to try to balance this out.
Not a good idea.
Andy
The average salt content of body fluid is too saline, and cellular fluid migrates to try to balance this out.
Not a good idea.
Andy
CodStewart
Well-Known Member
Re: osmosis
He he! Would be hard to find somewhere high enough in the raft to hang the bag.
He he! Would be hard to find somewhere high enough in the raft to hang the bag.
robind
Well-Known Member
Re: osmosis
Does that mean that sea water is not saline enough? When you say it is not a good idea why is this (in idiots terms please)? Bombard drank sea water whilst crossing the Atlantic just to prove a point. wouldnt sea water enemas slow down the dehydration process? sorry to appear so ignorant, but I am.
Kind regards and thanks
Rob
Does that mean that sea water is not saline enough? When you say it is not a good idea why is this (in idiots terms please)? Bombard drank sea water whilst crossing the Atlantic just to prove a point. wouldnt sea water enemas slow down the dehydration process? sorry to appear so ignorant, but I am.
Kind regards and thanks
Rob
phanakapan
Well-Known Member
Re: osmosis
Just read a book - very famous one but too late at night to remember which one! about a family who were shipwrecked, not found for more than a month, wife administered sea water enemas which she beleived did more good than harm (she was a nurse)
Just read a book - very famous one but too late at night to remember which one! about a family who were shipwrecked, not found for more than a month, wife administered sea water enemas which she beleived did more good than harm (she was a nurse)
Benbow
Well-Known Member
Re: osmosis
Unfortunately what Andy_wilson wrote was exactly the wrong way round. Sea water has a higher salt content than physiological saline (and your cells). So there would be a net loss of water from you into the seawater. It makes no difference into which orifice you shove it!
However, the difference is small; normal saline is taken as 0.09% NaCl (anyone know what sea water is?). So I guess that if you are already in terminal dehydration, then it may not make you any worse. I don’t know if sea-water salt concentrations are lethal to human physiology but someone must have done the work. The bottom line may be that if you are absolutely 100% certain you are dehydrated to the point of death, it may be worth a try. Until that point it will certainly make you much worse.
Unfortunately what Andy_wilson wrote was exactly the wrong way round. Sea water has a higher salt content than physiological saline (and your cells). So there would be a net loss of water from you into the seawater. It makes no difference into which orifice you shove it!
However, the difference is small; normal saline is taken as 0.09% NaCl (anyone know what sea water is?). So I guess that if you are already in terminal dehydration, then it may not make you any worse. I don’t know if sea-water salt concentrations are lethal to human physiology but someone must have done the work. The bottom line may be that if you are absolutely 100% certain you are dehydrated to the point of death, it may be worth a try. Until that point it will certainly make you much worse.
robind
Well-Known Member
Re: osmosis
Has anyone done the work out there? is there any point progressing this post further. would the partial use of a solar still provide a suitable amount of usable saline solution, that would have the capacity to rehydrate
Rob
Has anyone done the work out there? is there any point progressing this post further. would the partial use of a solar still provide a suitable amount of usable saline solution, that would have the capacity to rehydrate
Rob
Benbow
Well-Known Member
Re: osmosis
Oops, I seem to have an extra zero in there. Normal saline is nominally 0.9% NaCl.
Google suggest sea water is 3.5% NaCl – not as close as I had thought.
Thus to make physiological normal saline you would need to add approx 1 volume of sea water to 2.5 volumes of fresh water. (although I am told that water from solar stills is pretty salty which may wreck these sums)
You then MAY have a safer way of rehydrating a severely dehydrated patient than water alone because of reduced osmotic damage to an already knackered gut and a less rapid increase in blood volume. Certainly in a controlled environment with known accurate saline, it would be better.
But in a survival situation, if I had the water I would just give it slowly by mouth. Even if there was a luscious nurse poised with a hose pipe.
Oops, I seem to have an extra zero in there. Normal saline is nominally 0.9% NaCl.
Google suggest sea water is 3.5% NaCl – not as close as I had thought.
Thus to make physiological normal saline you would need to add approx 1 volume of sea water to 2.5 volumes of fresh water. (although I am told that water from solar stills is pretty salty which may wreck these sums)
You then MAY have a safer way of rehydrating a severely dehydrated patient than water alone because of reduced osmotic damage to an already knackered gut and a less rapid increase in blood volume. Certainly in a controlled environment with known accurate saline, it would be better.
But in a survival situation, if I had the water I would just give it slowly by mouth. Even if there was a luscious nurse poised with a hose pipe.
robind
Well-Known Member
Re: osmosis
I like the bit about the luscious nurse!
Thanks for that info
Regards
Rob
I like the bit about the luscious nurse!
Thanks for that info
Regards
Rob
vyv_cox
Well-Known Member
Re: osmosis
My recollection of the book is that the enemas administered were not 100% seawater but "fresh" water contaminated with some seawater. The process was universally hated by the family but did help to keep them alive.
My recollection of the book is that the enemas administered were not 100% seawater but "fresh" water contaminated with some seawater. The process was universally hated by the family but did help to keep them alive.
anglo_saxon
Well-Known Member
Re: osmosis
i was told that sea water can be administered through the rectum in small doses as the membrane is so fine that only the water can pass by osmosis and that a french family in a liferaft kept them selves alive by doing so. but i havn`t tried it and i hope i never have to.
i was told that sea water can be administered through the rectum in small doses as the membrane is so fine that only the water can pass by osmosis and that a french family in a liferaft kept them selves alive by doing so. but i havn`t tried it and i hope i never have to.
Benbow
Well-Known Member
Re: osmosis
I can absolutely assure you that is untrue. If you have anything like normal levels of hydration, you WILL loose water from yourself into the seawater.
Osmosis is a flow of water that 'attempts to equalise salt concentrations'. Without active pumping* you are at the mercy of the simple fact that salt levels in sea water are 3.5 times higher than in your cells, so water goes from you into the sea.
If you dry-out a human, there will come a point when water will flow the other way, but I strongly suspect that will happen some time after death.
Someone said it was actually salt-contaminated water that had been used in this way. As long as the salt concentrations are low enough (ie 3.5 times less than sea water) then that would help.
* horrible thought....may be if you pressurised the water by sticking the liferaft pump up your backside that would force water across the gradient......ie build a RO water purifier using your gut as the membrane......no just kidding
I can absolutely assure you that is untrue. If you have anything like normal levels of hydration, you WILL loose water from yourself into the seawater.
Osmosis is a flow of water that 'attempts to equalise salt concentrations'. Without active pumping* you are at the mercy of the simple fact that salt levels in sea water are 3.5 times higher than in your cells, so water goes from you into the sea.
If you dry-out a human, there will come a point when water will flow the other way, but I strongly suspect that will happen some time after death.
Someone said it was actually salt-contaminated water that had been used in this way. As long as the salt concentrations are low enough (ie 3.5 times less than sea water) then that would help.
* horrible thought....may be if you pressurised the water by sticking the liferaft pump up your backside that would force water across the gradient......ie build a RO water purifier using your gut as the membrane......no just kidding
bobgosling
Well-Known Member
Re: osmosis
Wasn't this technique employed by the author of "Survive The Savage Sea" ?
Didn't seem to do him any harm ?
Wasn't this technique employed by the author of "Survive The Savage Sea" ?
Didn't seem to do him any harm ?
andy_wilson
Well-Known Member
Re: osmosis
Quite right, I think I missed some words out. Basic mechanism is cellular fluid migrating through cells walls to balance salt level in rest of body.
Quite right, I think I missed some words out. Basic mechanism is cellular fluid migrating through cells walls to balance salt level in rest of body.
Sultans_Kapitein
RIP
Re: osmosis
I seem to recall somewhere reading that the contents of coconuts make good saline, so if you are in tropical waters maybe they would be a possible help. I don't know whether this was someones flight of fantasy, but I suppose if you had coconuts you drink them !? Sorry for going off at a tangent, seem to do alot of that lately... /forums/images/graemlins/confused.gif
I seem to recall somewhere reading that the contents of coconuts make good saline, so if you are in tropical waters maybe they would be a possible help. I don't know whether this was someones flight of fantasy, but I suppose if you had coconuts you drink them !? Sorry for going off at a tangent, seem to do alot of that lately... /forums/images/graemlins/confused.gif
anglo_saxon
Well-Known Member
Re: osmosis
must remember to take the pipe out of the grab bag. /forums/images/graemlins/grin.gif
must remember to take the pipe out of the grab bag. /forums/images/graemlins/grin.gif
Sultans_Kapitein
RIP
Re: osmosis
Would that be the Briar or the Meerschaum ? /forums/images/graemlins/smile.gif
Would that be the Briar or the Meerschaum ? /forums/images/graemlins/smile.gif
tyce
Well-Known Member
Re: osmosis
ive been on quite a few seasurvival courses when i was in the M.N. and all recommended using this method as the salt can not be absorbed thro the gut.
incidentally fish eyes are another source of fresh eater
ive been on quite a few seasurvival courses when i was in the M.N. and all recommended using this method as the salt can not be absorbed thro the gut.
incidentally fish eyes are another source of fresh eater
Benbow
Well-Known Member
Re: osmosis
[ QUOTE ]
.... salt can not be absorbed thro the gut....
[/ QUOTE ]
That is not the point. The point is that WATER cannot move out of seawater into you because that would be against an osmotic gradient. In fact it moves the other way.
Are you really saying that in a survival course you were told that a seawater enema was a means of taking in water??
[ QUOTE ]
.... salt can not be absorbed thro the gut....
[/ QUOTE ]
That is not the point. The point is that WATER cannot move out of seawater into you because that would be against an osmotic gradient. In fact it moves the other way.
Are you really saying that in a survival course you were told that a seawater enema was a means of taking in water??
wooslehunter
Well-Known Member
Re: osmosis
So don't thing just come together. This is a rare visit to the liveaboard forum for me. Also I was scanning through a book last night & came across a piece on just this subject. I'd recommend the book to anyone - "Essentials of Sea Survival" by Dr. Frank Golden DM PhD & Prof Michael Tipton PhD. Published by Human Kinetics.
I'm not a medical man but here's a summary.
The family refered to above were the Robertsons. Their 19-ton 13 meter schooner, Lucette was attacked by a killer whale & sunk about 200 miles west of the Galapagos on 15th June 1972. It sank in less than 4 minutes. The couple had three children (18 & 12 year old twins) plus a deck hand. They managed to get away in the life raft & also launched their dinghy. They had 10l of water plus some salvaged fruit. The raft also had food for 10 for 2 days.
They started water rationing immediately. On the third day it rained but they were forced to discard the collected watare as the recepticals contaminated it. Thereafter, they made sure the recepticals were clean when the rain arrived. On the 7th day it rained again. However as they could not store much water, by the 15th day the situation was becomming critical again so Mrs. Robinson, a qualified nurse suggested using the unpalatable water as an enema.
The raft turned out to be in poor condition so on the 17th day they ewere forced to abandon it & took to the tender. They had lots of rain on days 22 & 23 and devised a way to use the compartments of the damaged life raft to store the water. This extra water together with turtle blood kept them alive until they were picked up by a Japanese trawler on day 38.
On the subject of enemas, Tipton & Golden, say that there is no scientific evidence to support the claim that water is absorbed through the gut leaving unwanted salt behind in the bowel. They site two experiments: Foy et al (1942) & Bradish et al (1942). The first deprived 6 male volunteers of water for 80 hours. Three were then given sea water enemas of 1500ml while the others acted as controls. The researchers found the subjects could not retain the water because of violent colic & associated diarrhea. Thereafter 4 daily doses of 200ml were given. These were only retained with considerable effort. During the tests blood tests were done. Salt concentrations in both groups increased. In the control group it was due to dehydration. Further, urine output in the enema group increased with the volume well above the volume of water administered rectally, showing increased dehydration. In addition, body weight losses were greater in the enema group indicating worse dehydration. The researchers concluded that seawater enemas could not be of any beneficial value and would be posively harmful.
In the second study in the US, the researchers found that the large bowel was not capable of concentrating sea water. They noted the difficulty in retaining the enema. The volume retained was absorbed along with its concentration of salts. These researchers advised that sea water enemas would neither alleviate dehydration nor prolong life but instead would hasten death from dehydration.
Appologies to the authors if I've missed anything.
There's a whole load as well on the subject of drinking seawater. Basically this is a bad thing and could the commonest cause of death amongst shipwrecked sailors next to cold - Critchley giving the bradshaw lecture in 1942.
Great book with lots of real life stories plus lots of scientific evidence.
So don't thing just come together. This is a rare visit to the liveaboard forum for me. Also I was scanning through a book last night & came across a piece on just this subject. I'd recommend the book to anyone - "Essentials of Sea Survival" by Dr. Frank Golden DM PhD & Prof Michael Tipton PhD. Published by Human Kinetics.
I'm not a medical man but here's a summary.
The family refered to above were the Robertsons. Their 19-ton 13 meter schooner, Lucette was attacked by a killer whale & sunk about 200 miles west of the Galapagos on 15th June 1972. It sank in less than 4 minutes. The couple had three children (18 & 12 year old twins) plus a deck hand. They managed to get away in the life raft & also launched their dinghy. They had 10l of water plus some salvaged fruit. The raft also had food for 10 for 2 days.
They started water rationing immediately. On the third day it rained but they were forced to discard the collected watare as the recepticals contaminated it. Thereafter, they made sure the recepticals were clean when the rain arrived. On the 7th day it rained again. However as they could not store much water, by the 15th day the situation was becomming critical again so Mrs. Robinson, a qualified nurse suggested using the unpalatable water as an enema.
The raft turned out to be in poor condition so on the 17th day they ewere forced to abandon it & took to the tender. They had lots of rain on days 22 & 23 and devised a way to use the compartments of the damaged life raft to store the water. This extra water together with turtle blood kept them alive until they were picked up by a Japanese trawler on day 38.
On the subject of enemas, Tipton & Golden, say that there is no scientific evidence to support the claim that water is absorbed through the gut leaving unwanted salt behind in the bowel. They site two experiments: Foy et al (1942) & Bradish et al (1942). The first deprived 6 male volunteers of water for 80 hours. Three were then given sea water enemas of 1500ml while the others acted as controls. The researchers found the subjects could not retain the water because of violent colic & associated diarrhea. Thereafter 4 daily doses of 200ml were given. These were only retained with considerable effort. During the tests blood tests were done. Salt concentrations in both groups increased. In the control group it was due to dehydration. Further, urine output in the enema group increased with the volume well above the volume of water administered rectally, showing increased dehydration. In addition, body weight losses were greater in the enema group indicating worse dehydration. The researchers concluded that seawater enemas could not be of any beneficial value and would be posively harmful.
In the second study in the US, the researchers found that the large bowel was not capable of concentrating sea water. They noted the difficulty in retaining the enema. The volume retained was absorbed along with its concentration of salts. These researchers advised that sea water enemas would neither alleviate dehydration nor prolong life but instead would hasten death from dehydration.
Appologies to the authors if I've missed anything.
There's a whole load as well on the subject of drinking seawater. Basically this is a bad thing and could the commonest cause of death amongst shipwrecked sailors next to cold - Critchley giving the bradshaw lecture in 1942.
Great book with lots of real life stories plus lots of scientific evidence.