Dehydration
is not usually a factor in urban first aid. In the wilderness, however,
it often affects us more than we think. Dehydration is what occurs
when the body loses more water than it takes in.
Dehydration is usually
caused by: not drinking enough
losing to much water through
the skin by perspiration
losing too much water through
the lungs by evaporation
losing water through vomiting
or diarrhea
frequent urination
Because of the cold,
very dry air of the north, especially in winter, evaporation is very rapid,
and a person who is working hard outdoors for several days with little
opportunity to drink may become severely dehydrated, and may show signs
and symptoms similar to shock. But Dehydration by itself is
not usually the main problem, for almost everyone if they can will eventually
satisfy his/her thirst with the needed fluids. The combination
of dehydration and other conditions may be a real problem.
Suppose for example,
an active hunter has lost 5% of his/her total blood volume by dehydration.
The body will compensate - much as is does for shock - by reducing blood
flow to the skin. This makes the skin colder and much more likely
to be frostbitten.
Suppose the same hunter
is injured and loses blood. Since his/her blood volume is already
decreased, it takes less blood loss to produce shock.
Suppose that the same
hunter had a chest injure or a respiratory infection. Because the
body fluids have become more viscous (thicker and stickier) from dehydration,
it is harder for the hunter to cough up the fluids which accumulate in
the lungs.
PREVENTION
To balance normal water
loss, simply drink more water during outdoor activity. Try to drink
often even if you don't feel thirsty. The traditional tea/coffee
stop while traveling is very valuable in the and other ways, although tea
and coffee are not as good as plain water or the broth from boiled meat,
because tea and coffee are diuretics (that is, they make you urinate more).
Alcohol should not be drunk, as is increases dehydration.
(In fact, much of the discomfort of a hangover is due to dehydration brought
on by too much alcohol.)
Although you can reduce
this thirst for a short time by nibbling on snow, remember that melting
any amount of snow in your mouth takes an enormous amount of heat from
your body and produces little water. Any water you can get, no matter
how icy, will use up less body heat and be more thirst quenching.
Most northerners have
heard stories about people that were trapped without water and "survived"
by drinking their own urine. If the stories are true, it is likely
they survived in spite of drinking urine, not because of it.
Neither urine nor sea water should be drunk, even in small quantities,
as the salts in them will draw further water from your tissues.
Dehydration in babies
is very dangerous, and accounts for many millions of deaths worldwide each
year. Most of this dehydration is due to diarrhea or vomiting.
A baby can not tell you if he/she is thirsty, and it is easy to overlook.
It is also easy for seniors to become dehydrated.
Dehydration by normal
means is best combated by plain water or other ordinary drinks. Dehydration
due to vomiting or diarrhea should be fought using Gatorade or the salt,
soda, and sugar mix found at the bottom of this page which is also a fluid
for burn Casualties.
How to Tell
A mildly dehydrated person
may show some or all of the following signs:
thirst
dry tongue
discomfort
tiredness
nausea
sleepiness
pale, cool clammy skin
faster pulse
pinched skin on back of
hand slow to flatten out
little urine, dark in color
A person who is getting
adequate fluids and is healthy will produce at least 1,000 ml (about 4
cups) of urine each 24 hours. When a baby cries but produces no tears,
look for dehydration.
The "recipe" for
an excellent oral fluid is:
2.5 ml (1/2 tsp.) Salt
2.5 ml (1/2 tsp.) Baking
Soda (not baking powder!!)
1 litre (1 quart) of
water
sugar to taste
Next: Shock
, What it is and how to treat it! |