Monday, November 9, 2009

Wilderness Survival Myths

Survival in an emergency situation in the wilderness often depends on being able to sort out myth from reality.People who find themselves in precarious scenarios may be forced to deal with such things as how to stop bleeding, how to help a snake bite victim and how to treat a badly sprained ankle. Knowing what works and what is an old wives' tale can be of great aid and possibly even save a life.


Many people have heard that the best way to stop bleeding is by using a tourniquet. Nothing could be further from the truth. The tourniquet should be the last resort and is only a viable choice if someone has lost a limb or a limb has been partially rendered from the body by a horrible accident. The pressure that a tourniquet applies will severely damage blood vessels and can often result in tissue death, making it possible that a limb will need to be amputated. Heavy bleeding should be handled by applying pressure directly to the wound or to the area right above or below the wound. Once bleeding has been controlled the wound can be cleaned, packed and a pressure bandage applied. Less serious wounds should be allowed to bleed until they stop as this process will usually keep any organisms capable of causing infection from entering the wound.

(Correct Use of Tourniquet)
When should you apply a tourniquet? The simple answer: almost never. Tourniquets severely restrict or occlude blood flow to the arm or leg to which they are applied. Using a tourniquet to stop bleeding has the potential to damage the entire arm or leg. Patients have been known to lose limbs from the use of tourniquets.
Often, if a tourniquet doesn't cause a loss of function on the extremity which has it, then it probably wasn't applied correctly. Applying a tourniquet is a desperate move - only for the most dire emergencies where the choice between life and limb must be made.
For a step-by-step guide, see How to Use a Tourniquet.
Using a tourniquet requires wrapping a cravat (non stretchy material like terry cloth or linen) around an extremity and tightening it with the use of a windlass stuck through the bandage (see photo).
The tourniquet should be tightened until the wound stops bleeding. If there is any bleeding at the wound after placing a tourniquet, then the tourniquet must be tightened.
When a tourniquet is applied, it is important to note the time of application and write that time down somewhere handy. The best bet is to write the time on the patient's forehead with a water-proof marker

Snake Bites
Many misconceptions and myths surround snake bites and how these dilemmas should be treated. A rattlesnake does not always warn someone of an impending attack as is widely thought, and even though this species has potent venom a person rarely receives a full dose of it when bitten. Many times, no venom at all is injected into the person. When a person is bitten by a suspected poisonous snake, a tourniquet should never be applied for the reasons previously mentioned, and the area should not be cooled or iced. The myth that cutting an "X" shaped incision over the wound and then sucking the venom out, perpetuated by countless examples on film and television, has never been proven to provide any relief. This procedure in truth would only be responsible for tiny volumes of the venom being removed from the bloodstream but would make the person vulnerable to extremely dangerous infections. The proper way to treat snakebite is to clean the wound thoroughly with soap and water and to keep the bitten area below heart level. If possible, carry the person to a vehicle and get her prompt medical attention; if she must walk then have her move slowly.

(For Correct Survival Treatment - See previous posted blog here dated Nov.9.09 "Surviving a snake bite")

Sprained Ankle

How to treat a badly sprained ankle, which for a hiker or backpacker can be a serious situation when out in the wilderness, has always been subject to myth, with a large portion of the population thinking that warmth should immediately be applied. However, the opposite is true since heat will make the swelling and pain increase and slow down the healing process. If you spend time on trails and out camping, REMEMBER "RICE". This stands for Rest, Ice, Compression and Elevation. The ankle should be quickly rested and iced if possible or soaked in cold water from a stream. Even snow can be used as a substitute for ice. Ice the ankle for 20 minutes to half an hour and then put a compression bandage such as an elastic wrap on it to give it support. Elevate the affected foot. Repeat this procedure up to four or five times a day until the swelling goes down.

As a wilderness survival enthusiast I have come upon many questionable survival tips and half truths presented as fact. Unfortunately there is a great deal of survival related advice that does not actually work, or works poorly, when attempted in actual field conditions. Either the information is downright incorrect or there are vital pieces missing that put a successful outcome doubtful at best, and very dangerous at worst.
Many who relate their survival skills to others are more of the arm chair variety than real life doers. From the safety of ones home survival misinformation may seem harmless and few are the wiser. All too often these bad survival skills are merely passed on from one armchair enthusiast to another and over the years take on a mythical standing, so much so that most people consider them as facts.

Cactus Water Myth

One survival myth in particular that nearly everyone has heard is what I call the "cactus water myth". As the story goes, if you are thirsty in a desert all you need to do is lop the top off a cactus to find plenty of sweet water to drink. The common association with this myth is that a cactus must be something like a spiny watermelon with plenty of cool refreshing water just waiting to be tapped into. Nothing could be further from the truth.
Surviving on water from a cactus is generally a very bad idea. First of all, the amount of water you are likely to obtain from a cactus is minimal - its inside is tough and fibrous. Indeed, it is possible to obtain some moisture from the inside of a cactus but it is not pure water. Often cactus water is slimy and highly acidic. The survival fact is that drinking cactus juice like this may only lead to further dehydration.
But it gets worse. Should you be unlucky enough to obtain and drink plenty of cactus juice you are likely to be further dehydrated by intense vomiting and diarrhea. Cactus juice may burn your mouth, throat, and the lining all the way into your intestines. So much for a cool refreshing drink.

The few times I have had the pleasure of choking down barrel cactus fluid (notice I didn't say "water") made my stomach churn like a cement-mixer and required a Buddhist's monks meditative effort, that's humor for ya,  at keeping from vomiting. 

Save the romantic notions for the Hollywood westerns and rely on this method only if there is no other alternative. By the way, the only barrel cactus that isn't toxic is the fishhook barrel (Ferocactus

asdm041(So, Can you get Potable water from a Cactus?) 
Lets explain why the answer is a resounding NO!

NO, because the moisture within the pulp of a cactus is very acidic and many cacti contain toxic alkaloids. You can, however, eat the fruit.( but that is another post)
The moisture is acidic because of the way many succulents, including cacti, carry on photosynthesis, the process by which carbon dioxide and water are turned into carbohydrates.
Most plants have their pores (stomates) open during the day to take in carbon dioxide, and use sunlight as a catalyst for the reaction: Carbon dioxide + water sugar + oxygen. But in the desert, plants with pores open during the hot days, lose much water through evapotranspiration.
So, succulents use a modified version of photosynthesis called CAM (Crassulacean Acid Metabolism). CAM plants open their stomates only at night when it is cooler so there is less evapotranspiration. Because there is no sunlight to act as a catalyst, carbon dioxide is stored as an organic acid, principally Malic Acid (C4H6O5). Carbon dioxide is gradually released from the acid during the next day. CAM plants use about one-tenth the water to produce each unit of carbohydrate compared to standard photosynthesis. The price: a much slower growth rate.
Many plants contain malic acid, but usually in lesser quantities than found in cacti. Also cooking generally destroys the acid.
Besides malic acid, succulents produce Oxalic Acid (C2H2O4), which is toxic, as another product of photosynthesis. “Its chief function seems to be sequestering metals, principally calcium. Calcium oxalates often occur as crystalline minerals within the cactus pulp. Their function seems to be aiding structural integrity and enzymatic processes. In fact two crystalline calcium oxalate minerals have been identified in all cacti tested: CaC2O4.2H2O (weddellite) and CaC2O4.H2O (whewellite).” [Source: Plant Physiology, February 2002, Vol. 128, pp. 707-713.] Oxalates are also formed with heavy metals such as copper, perhaps to reduce toxicity to the plant.

**Oxalic acid is toxic to humans because it combines with calcium in our bodies to produce calcium oxalates which clog up our kidneys**

So, what about the barrel cactus. Can’t we get water from those? Did you bring along a machete and solar still?
The Seri Indians sometimes used the Fishhook barrel (Ferocactus wislizeni) for emergency water. However, drinking the juice on an empty stomach often caused diarrhea, and some Seri report pain in their bones if they walk a long distance after drinking the juice. The Seri called the Coville barrel (Ferocactus emoryi), “barrel that kills” because eating the flesh of the cactus causes nausea, diarrhea, and temporary paralysis. Think you can tell the two apart? (See: Edible Desert Plants – Barrel Cactus Fruit).
What about Prickly Pear pads we sometimes see in grocery stories or on the menu of Mexican restaurants? What you see are generally young spring pads which naturally contain less oxalic acid. Cooking leaches out the acid. In an emergency you can eat the young pads raw. And there are some spineless cultivars that naturally contain little oxalic acid which can also be eaten raw. These were developed mainly as cattle feed.

The bottom line is this: Your in a crap shoot against survival and in my opinion and the facts are stated. You should NOT attempt to get a drink from a cactus in spite of what you may have seen in old cowboy movies or survival tapes and discovery channel shows, without accepting that your dehydrated body stands the likely hood of your damaging it's natural water filters; ie: your kidneys and digestive tract, exposing your weakened body to even more so with toxicity. Just m,y humble opinion shared.

No comments:

Post a Comment