Sunday, August 5, 2007

MYTHS OF SNAKES AND SNAKE-BITES


Introduction
Since Adam and Eve, snakes have long been portrayed as evil creatures to be feared. Our history is long, and myths and phobias are hard to break. Built into their religious practice, Pentecostal Movement preachers in the hills of Tennessee handle rattlesnakes. They now struggle with local law enforcement since rattlesnakes are protected in many states. Aboriginal groups in Australia hold the snake in high esteem, and it is a symbol of fertility. Native Americans felt that snakes symbolized life cycles and truth.

There are widespread myths regarding snakes:

Snakes hold their tails in their mouths to create a circle and will chase you.
When you kill a snake, another one will chase you (ironically, what IS true is excessive killing of snakes leads to the overpopulation of rodents and more disease
states).
Snake Bite Facts
In the United States, only about 12 people a year die from snakebites.
The estimated chances of dying from a snakebite in the outdoors is approximately 1:10 million.
Victims of snakebites in North America usually have two common denominators, tattoos and alcohol intake.
There are approximately 23 different subspecies of rattlesnakes in the United States including the coral snake, copperhead and cottonmouth (or water moccasin), which comprise the venomous snakes indigenous to the United States. We emphasize indigenous to the United States in that due to the internet, more and more exotic/foreign snakes are being brought into the United States illegally. This is an extremely dangerous practice, posing enormous diagnostic and treatment risk for emergency rooms across the United States. Every month, there are incidents that occur where someone is tired of their exotic and most likely illegally owned pet and releases it, or possibly it escapes. Example: A few months ago, a friend of Survive Outdoors from Indiana was helping someone move when he found a king cobra in the bushes outside of the home. The cobra was poised and ready to strike; luckily no one was bitten.
There are two types of venomous snakes, falling into two separate categories, the pit vipers which include the rattlesnakes, copperheads and coppermouths, and the elapids, which are coral snakes.

Pit Viper
The pit viper has thermoreceptors, or “pits,” on their heads. These organs help the snake locate prey and adjust the amount of venom used according to the size of their prey. The glands, or venom sacks are connected to the fangs, which act like hollow hypodermic needles. These fangs are voluntarily controlled by the snake. They can raise either one or both fangs, or neither. When fangs break off, there is usually another fang below, or there may be one next to it. Therefore, snakebites can present as one puncture wound, two, three or even four (see photo of timber rattlesnake for example of multiple fangs).

The pit viper can strike about 50% of its body length, and has been recorded to strike at about 7 feet per second. The forked tongue is equivalent to our nose. The snake senses chemicals in the air with their tongue, aiding in the location of prey. Their pupils are elliptical, and all pit vipers in the United States have elliptical pupils, as opposed to non-venomous snakes which have round pupils.

The age of a rattlesnake cannot be determined by the number of rattles. Rattles frequently break off, and therefore is an unreliable method to determine age.

Elapids
Elapids in the United States consist only of the coral snake. They have red, yellow and black bands around their bodies. King snakes are very similar in color. However there is a slight difference in band sequence. Mnemonics have been created to aid in remembering the differences, such as “red on yellow, kill a fellow, red on black, venom lack,” or “red on yellow, kill a fellow, red on black, friend of Jack.”

It is best not to pick up any snake, thereby greatly reducing your chance of being bitten.

Elapid fangs are fixed as opposed to the retractable fangs of the pit viper, and are much smaller. A coral snake must chew on its victim to inject enough venom to cause damage.
Small children are bitten by handling the snake, and due to its attractive coloring, it becomes a visual “draw” for the child, who wants to pick up the “sparkling gemstone.”

Venoms
Venoms of the pit viper contain peptides and proteins. The venom leads to damage of vascular cells and red blood cells. Proteolytic enzymes damage muscle and are responsible for tissue death. There is also a histamine release by the body after the bite.

Juvenile rattlesnakes do have more toxic venom; however, they do not inject the large amount of venom as adult rattlesnakes do.

Coral Snake Bite Symptoms
Coral snake venom is different than pit viper venom. As per Auerback, it is thought that adult coral snakes carry enough venom to kill 4-5 adults. The coral snake venom is primarily a neurotoxin. Fang marks are rarely seen. Swelling is rare. Symptoms may not occur until 10-14 hours later. Symptoms may begin as nausea, vomiting and sweating. Neurological symptoms may include lethargy, difficulty speaking, hard to swallow, drooping eyelids, and in severe cases, respiratory depression or arrest.

Dry Bites
Dry bites are referred to as “misses,” no venom injected due to the lack of venom, a glancing blow, or penetration could not occur because of the clothing worn by the individual. Dry bites account for about 20-30% of all snakebites.

Pit Viper Bite Symptoms
There are many symptoms associated with the bite of a pit viper. Fang marks are always present, followed by swelling, pain, and black and blue marks on the skin. Sweating, chills and muscle twitching are commonly seen. Some feel numbness on the tongue, and reports of a metallic taste are not uncommon.

Snakebite Treatment for Pit Vipers
General support/reassurance; keep the victim calm; move the individual away from the snake, if possible; do not try to kill the snake—two people being bitten is worse and you cannot aid the first victim (note: amputated snake heads can still bite as a reflex).
Minimize all activity.
All jewelry, rings, bracelets and watches should be removed immediately.
Do not incise the wound as this causes more tissue damage.
Do not use electrical shock at the bite site as that has been shown not to work.
Sawyer extractor kits are controversial. Studies on pigs have shown little to no effect, while others recommend to only use the suction device if you can reach the victim in the first 3 minutes.
Do not suction with your mouth as the bacterial in your mouth will most likely cause more harm.
Apply cool compresses, not ice.
The Australian wrap method has proven benefit. Please see diagram. Do not wrap too tightly, but similar to wrapping a sprain.
Splint is very important. Immobilize the extremity, maintain the extremity at heart level, do not elevate above heart level.
Do not use Anti-venom in the outdoors. Many have anaphylactic type reactions from the anti-venom.
Transport, transport, transport.
Call ahead if possible to the ER. Many emergency rooms do not stock anti-venom and they may need to fly anti-venom in.
Anti-venom is very, very expensive. When traveling into the outdoors for an extended period of time, check into search and rescue insurance. Many times anti-venom is covered. It is as cheap as $12-20 for a weekend, and is well worth it if something unfortunate should occur.
Snakebite Treatment for Coral Snakes
Remember, bite symptoms from this snake are usually delayed.
In this situation, if possible, it could be very helpful to capture the snake for identification purposes since it does mimic the king snake.
The Australian wrap method is highly touted for this bite.
Transport, transport, transport.
All other treatment for the coral snake should be the same as for the pit viper.
Summary
Snakes, like sharks, have a bad reputation, as the media love to sensationalize these critters. Fear sells. If you see a snake, please do not kill it! It does a tremendous amount of good, compared to any harm done. Understand reality and not fall prey to your fears and phobias.

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