Snake Bit

Faculty of Medicinee Ain shams university Department of toxicology

SNAKE BITES Edited BY/ Mohammed Ahmed Ghanem

SUPERVISOR / DR. MARY

Snake bites

by Mohamed A. Ghanem

2008

Aim of the search 

To spot light on snake bites types.

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To spot light on effects of snake bites.

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To spot light on first aid in case of bit.

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Treatment procedure of snake bite.

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To spot light on mechanism of snake venoum.

Introduction Snakes often bite their prey when feeding, but occasionally they also bite humans. People can avoid and treat snakebites by knowing their etiology, along with prevention tips, and first-aid and hospital treatment.

ENVENOMATION Most snakebites are caused by non-venomous snakes. Of the roughly 3,000 known species of snake found worldwide, only 15 percent are considered dangerous to humans.Snakes are found on every continent except Antarctica. Venomatous snakes : Poisonous snake bites include bites by any of the following:Cobra , Copperhead ,Coral snake ,Cottonmouth (water moccasin),Rattlesnake.

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Snake bites

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year, Frequency and statistics : some estimates put the number at 2.5 million bites per year resulting in perhaps 125,000 deaths. Worldwide, snakebites occur most frequently in the summer season when snakes are active active and humans are outdoors. Agricultural and tropical regions report more snakebites s than anywhere else. Victims are typically male age Map showing global distribution of snakebite and between 17 and 27 years of age. morbidity (fig.1).

[Fig. 1]

PREVENTION   

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Avoid areas where snakes may be hiding, such as under rocks and logs. Even though most snakes are not poisonous, avoid picking up or playing with any snake unless you have been properly proper trained. If you hike often, consider buying a snake bite kit (available from hiking supply stores). Do not use older snake bite kits, such as those containing razor blades and suction bulbs. Don't provoke a snake. That is when many serious snake bites occur. o Tap ahead of you with a walking stick before entering an area where you can't see your feet. Snakes will try to avoid you if given enough warning. When hiking in an area known to have snakes, wear long pants and boots if possible.

Symptoms In principle, ple, snake venoms act in three 'different' ways: ways Pa g e 3 o f

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Snake bites

by Mohamed A. Ghanem

2008

1. haemotoxins, ie venoms that split (haemolyse) the red blood cells, or affect the ability of the blood to clot (coagulate). 2. neurotoxins, ie venoms that in particular paralyse nerve transmission to the muscles and in the worst case paralyse the muscles involved in swallowing and breathing. 3. cardiotoxins, ie venoms that have a direct harmful action on the heart and lead to circulatory failure and shock. But as a number of other factors, including possible allergic allergic reactions, are also involved in poisoning, the situation is often far more complex and unclear, and there are often typically 'mixed' reactions and symptoms.

Symptoms depend on the type of snake, but may include: include Bleeding from wound ,Blurred vision ,Burning ,Burning of the skin ,Convulsions ,Diarrhea ,Dizziness ,Excessive sweating ,Fainting ,Fang marks in the skin ,Fever ,Increased thirst ,Loss of muscle coordination ,Nausea and vomiting ,Numbness and tingling ,Rapid ,pulse ,Tissue death, Severe pain, Skin discoloration, discoloration, Swelling at the site of the bite, WeaknessRattlesnake Rattlesnake bites are painful when they occur. a.Neurotoxic venom (Nerve destroying)         

The casualty has speech and swallowing difficulties often accompanied by drooling. Difficulty breathing. Respiratory arrest. Dizziness. Tunnel vision or blurred vision. Visible increase in sweating. Convulsions. Unconsciousness. This venom attacks the central nervous system by causing a high loss of the synaptic vesicles, resulting in the blockage of nerve impulses from the brain too the muscles.

b. Haemotoxic venom (poisoning of blood)    

Often no pain or symptoms occur for 1 -3 hours and as long as 8 hours. Casualty feels lethargic with headaches. Nausea and vomiting may occur. Constant bleeding from the bite bi wound. Pa g e 4 o f

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Snake bites

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by Mohamed A. Ghanem

2008

Bruising as well as blood spots may occur under the skin. Blood oozing from other bodily openings. This venom affects the blood clotting mechanism, resulting in headaches, and loss of blood through the bodily openings and if left untreated internal intern bleeding of the organs will occur.

Treatment F i r s t

a i d

1. Keep the person calm, reassuring them that bites can be effectively treated in an emergency room. Restrict movement, and keep the affected area below heart level to reduce the flow of venom. 2. If you have a pump suction device (such as that made by Sawyer), follow the manufacturer's directions. 3. Remove any rings or constricting items because the affected area may swell. Create a loose splint to help restrict movement of the area. 4. If the area of the bite begins to swell and change color, the snake was probably poisonous.

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Snake bites

by Mohamed A. Ghanem

2008

5. Monitor the person's vital signs -- temperature, pulse, rate of breathing, and blood pressure -- if possible. If there are signs of shock (such as paleness), lay the person flat, raise the feet about a foot, and cover the person with a blanket. 6. Get medical help right away. 7. Bring in the dead snake only if this can be done safely. Do not waste time hunting for the snake, and do not risk another bite if it is not easy to kill the snake. Be careful of the head when transporting it -- a snake can actually bite for up to an hour after it's dead (from a reflex). 8. DO NOT  DO NOT allow the person to become over-exerted. If necessary, carry the person to safety.  DO NOT apply a tourniquet.  DO NOT apply cold compresses to a snake bite.  DO NOT cut into a snake bite with a knife or razor.  DO NOT try to suck out the venom by mouth.  DO NOT give the person stimulants or pain medications unless a doctor tells you to do so.  DO NOT give the person anything by mouth.  DO NOT raise the site of the bite above the level of the person's heart. P

R E S S U R E I MMOB I L I Z A T I ON

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pressure immobilization is not appropriate for cytotoxic bites such as those of most vipers but is highly effective against neurotoxic venoms such as those of most elapids. the object of pressure immobilization is to contain venom within a bitten limb and prevent it from moving through the lymphatic system to the vital organs in the body core a.Neurotoxic venom  Keep casualty calm and advise not to move. Either sitting or lying down.  Cover the site of the bite with a clean dressing and apply a pressure bandage from the start of the limb then wrapping towards the bite area.  Splint and elevate the limb if possible.  If a suction syringe is available, then use on the site of the bite within three minutes, any time after that would be prove useless. Don’t use your mouth to suck the venom out as you may have a cut or mouth ulcer where the venom can enter through.  Don’t cut the sight of the bite as this may lead to infection of the wound.  Keep the airways open and monitor respiration and heart rate. Pa g e 6 o f

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Snake bites

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by Mohamed A. Ghanem

2008

Mouth to mouth respiration may be required to keep the casualty alive. Try to identify the snake if possible but don’t waste time doing this. Don’t try catching the snake if it is still alive as this may result in another snake-bite. Transport casualty to hospital promptly. Neurotoxic venom is extremely powerful, so a tourniquet may be used if the casualty is far from any hospital. The tourniquet should be released and put back on every 10 – 15 minutes to allow for blood circulation.

b.Haemotoxic venom  Keep casualty calm and advise not to move. Either sitting or lying down.  Cover the site of the bite with a clean dressing and apply a pressure bandage from the start of the limb, then wrapping towards the bite area.  Splint and elevate the limb if possible.  If a suction syringe is available, then use on the site of the bite within three minutes, any time after that would be prove useless. Don’t use your mouth to suck the venom out as you may have a cut or mouth ulcer where the venom can enter through.  Don’t cut the sight of the bite as this may lead to infection of the wound.  Keep the airways open and monitor respiration and heart rate.  Try to identify the snake if possible but don’t waste time doing this. Don’t try catching the snake if it is still alive as this may result in another snake-bite.  Transport casualty to hospital promptly. Anti-venom  Anti-venom is made up of the antibodies from horses, sheep, goats, rabbits or dogs blood. Horses are more commonly used as more blood can be tapped.  These animals are injected with small, non-lethal doses of venom over a period of time, with the dosage slowly increased. Their immune systems respond by creating antibodies to attack the venom. Once the animal is immune to the venom, the antibodies are then extracted to make anti-venom.  Horse serum often causes serum sickness which is when the immune system reacts against the foreign proteins in the serum, the reaction can cause kidney failure and even death.  Sheep serum is made by a purified fraction of the plasma, specifically refined antibody fragments and is a lot safer to use. Sheep serum is used for the treatment of the American rattlesnake bites.

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Snake bites

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2008

A.Monovalent anti-venom – this is made by injecting the venom of a specific species of snake into an animal to develop the anti-venom. This is effective against one specific snake species. B.Polyvalent anti-venom – this is made by injecting the venom from a variety of different snake species into an animal to develop the anti-venom. This is effective against a broad range of snake species.

References 1. Wikipedia the free encyclopedia. http://en.wikipedia.org/wiki/Main_Page T

I T L E S NA K E B I T

2. Article base

T I T L E S N A K E V E N OM S Y MP T OMS A N D

T R E A T ME N T

http://www.articlesbase.com/environment-articles/types-of-snake-venomsymptoms-and-treatment-543049.html

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