Snake Bite

What is a snake bite?

A snake bite is a wound that you get from being bitten by a poisonous snake. A venomous (poisonous) snake bite is a bite caused by a snake that has venom (poison). Venomous snakes use venom to paralyze (cannot move) and start digesting (breakdown tissues) the prey animals they eat. A poisonous snake has two fangs (big pointed teeth) that inject the venom when it bites. When venom is released during a bite, it enters your tissues and spreads to other body parts. The venom can cause swelling, bleeding, and damage to your muscles, blood vessels, nerves, and other tissues. This can lead to low blood pressure, organ failure, and even death if not treated right away. Getting treatment within four hours after the bite may prevent the venom from spreading and causing these problems.

What types of poisonous snakes cause bite injuries?

There are many different species (types) of poisonous snakes that can cause venomous bite injuries:

• Snakes native to the United States: Venomous snakes live in all but three states (not Alaska, Hawaii, or Maine) in the United States (U.S.). Native snakes are those that are naturally found in an area.
  
  
  • Pit vipers: Rattlesnakes, copperheads, and cottonmouths (also called water moccasins) are pit viper snakes found in the U.S. These snakes have small heat-sensitive pits between their eyes and nostrils to sense their prey. They also have a large, triangle-shaped head.
    
    
  • Coral snakes: These colorful snakes with small heads are also found in the U.S. Coral snakes usually do not bite unless they feel they are being attacked. Their bites may be painless and easy to miss.
  
  
• Non-native snakes: Rarely, snake bites are caused by snakes that are not native to the U.S. These snakes include adders, asps, boomslangs cobras, kraits, mambas, sea snakes, and vipers. Bites caused by these types of snakes often occur when people have them for pets. Bites by these snakes may also happen in zoos and other places that keep such snakes. You may also encounter one of these snakes in the wild if you travel to other another country.

How do snake bites happen?

Snake bites in the U.S. are more common from April to September when the weather is warm. During this time, snakes are more active and people spend more time outdoors. Snakes may bite to defend themselves when they feel threatened. If you accidently step on a snake, you may be bitten on the foot or leg. This usually occurs when the snake is not moving and not seen, or is hidden by plants. Your foot is more likely to be bitten when you walk barefoot or wear only sandals. You may also be bitten, usually on the hard or arm, if you try to pick up a snake.

What are the signs and symptoms of a snake bite?

Signs and symptoms may be mild to severe, and may appear within minutes to hours after being bitten. You may have any of the following:

• You may not feel anything at first. You may see fang marks as one or more punctures (holes), or scratches on your skin. Within minutes after the bite, you may have any of the following:
  
  
  • Mild burning, tingling or prickling feeling, or numbness (no feeling) on the bite wound.
    
    
  • Redness and swelling on the bitten area of your skin.
  
  
• The venom may cause severe (very bad) skin and tissue damage after several minutes, hours, or days. You may see any of the following:
  
  
  • Severe swelling and pain at the site.
    
    
  • Enlarged lymph nodes in the groin (for bitten lower limb), or in the armpit (for bitten upper limb).
    
    
  • Bruise (bluish color) around the bite, or blisters that may become enlarged.
    
    
  • Bleeding from the wound or redness that may spread up the bitten limb.
    
    
  • Pus, ulcer (open wound with loss of skin), or black, dead tissue in the wound site.
  
  
• The venom may also act as a poison in your body. You may have any of the following:
  
  
  • Abdominal (stomach) pain, upset stomach, throwing up, loose bowel movements, or passing little or no urine.
    
    
  • Chest tightness, trouble breathing, or cyanosis (pale or bluish color of the skin, lips, or nailbeds).
    
    
  • Feeling anxious, weak, or dizzy, trouble thinking clearly, trouble staying awake, or having seizures (convulsions).
    
    
  • Fever or chills, headache, or having more sweat or spit than usual.
    
    
  • Muscle twitching, or unable to move your arms or legs.
    
    
  • Rubbery, minty or metallic taste, nose bleed, or having blood in your spit, vomit, or stool.
    
    
  • Tingling or numbness (loss of feeling) of your tongue, mouth, scalp, fingers, or toes.

What problems may come with having a snake bite?

Venom from a snake bite may damage different parts of your body. How fast these problems occur and how bad they are depends on the amount of venom you receive. Different snakes give different kinds and amounts of venom. Children usually develop more serious problems because of their smaller bodies. How bad the problems are may also depend on what body part you were bitten. Certain medical conditions may also worsen the effects of venom in your body. Venom may one or more of the following problems:

• Blood or blood vessel: The venom may interfere with your body's ability to stop bleeding and may damage red blood cells. You may have swelling and bruising in the area that was bitten. You may also have bleeding that happens in other parts of your body. Too much bleeding may lead to anemia (low amounts of red blood cells) and low blood pressure. Too little blood going to your organs may cause them to fail (not work properly).
  
  
• Muscle: Your arm or leg near where you were bitten may become very swollen and painful. Too much swelling may squeeze your blood vessels and nerves. Your skin may feel very tight or become numb (no feeling). The venom may also cause breakdown of your muscle tissues. When this happens, the cells, body salts, and chemicals inside your muscles may leak into your blood. These can lead to increased potassium levels in your blood, which may harm your kidneys or cause death.
  
  
• Nerves: The venom may damage your nerves and cause paralysis (unable to move). You may have a hard time opening your eyes, swallowing, breathing, or moving.

How is a snake bite diagnosed?

Your caregiver may ask you where and when you were bitten. Tell your caregiver if you know what kind of snake bit you or describe it to him. Your caregiver will closely look at your injury, and check the areas around it. He may press your skin in the groin or armpit area to feel the nodes. Your caregiver may use a measuring tape to measure around your bitten limb every now and then. This lets him check if your limb becomes swollen or if swelling increases. You may also need any of the following tests:

• Heart monitor: This test is also called an EKG or ECG. Sticky pads are placed on your skin to record your heart's electrical activity. An EKG gives information about how your heart is working. Lie as still as possible during the test.
  
  
• Blood tests: You may need blood taken to give caregivers information about how your body is working. The blood may be taken from your hand, arm, or IV.
  
  
• Urine test: A sample of your urine is collected and sent to a lab for tests.

How is a snake bite treated?

You may need any of the following:

• First-aid:
  
  
  • Stay calm, sit or lie down, and stay still. Avoid moving the part of your body where you were bitten. Too much movement may help spread the venom to other parts of your body.
    
    
  • Remove items on your body near the bite to prevent problems if swelling happens. This includes tight-fitting clothing and jewelry items such as rings, watches, and arm and ankle bracelets.
    
    
  • Keep the bitten area below the level of your heart. If the bite is on your arm or leg, immobilize the limb with a splint if possible.
    
    
  • See a caregiver right away. Do not wait until you have symptoms before seeing a caregiver.
    
    
  • Things you should not do:
    
    
    • Do not cut into the wound, or apply suction to try and remove the venom.
      
      
    • Do not use tourniquets, or apply heat, cold, or electric shock to the bite area.
  
  
• Anti-venom: This is the main treatment for poisonous snake bites. Most, but not all, poisonous snake bites need this treatment. This is most effective if given within four hours after you are bitten. It neutralizes the venom in your body, preventing it from causing more damage. You may need more than one dose of anti-venom. People who are allergic to papaya or other vaccines may be allergic to anti-venom. Tell your caregiver if you are allergic to any of these or have other allergies or medical conditions.
  
  
• Wound care: Your bite wound will be cleaned with soap, water, and germ-killing solutions. This helps wash away germs which may be in the wound, and decrease the chances of infection. If the wound area of tissue damaged by venom becomes large, surgical cleaning may be done. Damaged and dead tissues from the wound will be removed with surgical cleaning.
  
  
• Other treatments:
  
  
  • Intravenous therapy: You may get fluid through a tube placed in your vein (IV). IV fluids have water, sugar, protein, and mineral salt. This replaces the fluid you have lost, such as when throwing up.
    
    
  • Pain medicine: Caregivers may give you medicine to take away or decrease your pain.
    
    
    • Do not wait until the pain is severe to ask for your medicine. Tell caregivers if your pain does not decrease. The medicine may not work as well at controlling your pain if you wait too long to take it.
      
      
    • Pain medicine can make you dizzy or sleepy. Prevent falls by calling a caregiver when you want to get out of bed or if you need help.
    
    
  • Physical therapy: Your caregiver may want you to go to physical therapy. A physical therapist will help you with special exercises. These exercises help make your bones and muscles stronger. You may start physical therapy once your problems in the bitten area have cleared.
    
    
  • Td vaccine: This vaccine is a booster shot used to help prevent diphtheria and tetanus. The Td booster may be given to adolescents and adults every 10 years or for certain wounds and injuries.
    
    
  • More severe injuries: The chances of having severe injuries from a poisonous snake bite are small. If this occurs, you may need any of the following:
    
    
    • Blood transfusion: You will get whole or parts of blood through an IV during a transfusion. Blood is tested for diseases, such as hepatitis and HIV, to be sure it is safe.
      
      
    • Dialysis: Dialysis cleans your blood when your kidneys cannot. Extra water, chemicals, and waste products are removed from your blood by a dialyzer or dialysis machine. The dialysis machine does this by passing your blood through a special filter, then returning it back to you. You may need dialysis for a short time, or for the rest of your life. Caregivers will check your vital signs often during dialysis. You may also be given medicines or have blood taken for lab tests during dialysis.
      
      
    • Surgery: Surgery, called fasciotomy, may be done if there is too much swelling in your muscles. This is to cut tissues covering the muscles to decrease pressure on your blood vessels and nerves.
      
      
    • Ventilator: This is a machine that gives you oxygen and breathes for you when you cannot breathe well on your own. An endotracheal (ET) tube is put into your airway through your mouth or nose. You may need a trach if an ET tube cannot be placed. A trach is an airway tube put into an incision (cut) in the front of your neck. The ET tube or trach is attached to the ventilator.

How can a snake bite be prevented?

• Dress to protect yourself: Wear footwear and clothing to protect your feet and legs, such as shoes or boots, and long pants.
  
  
• Learn what poisonous snakes look like: Learn to recognize venomous snakes, especially if you spend much time outdoors. Learn to distinguish between similar-looking poisonous and non-poisonous snakes, such as coral snakes versus king snakes.
  
  
• Learn where snakes may be found: Know what snakes may be found where you are and where they may hide. Rattlesnakes rest in cool, shaded area during hot weather. Know when snakes are likely to be active and to come out. Stay away from places where snakes live. Do not put your hands or fingers into holes or places you cannot see.
  
  
• Leave snakes alone: Do not try to catch, frighten, or attack a snake if you find one. If you see a snake, back away from it and do not try to touch it. Do not pick up a snake that appears to be dead. Even dead snakes can still deliver venom through their fangs.
  
  
• Watch out for snakes: Use a flashlight or lamp when walking outside at night. Do not walk in areas where you cannot see the ground.

When should I call my caregiver?

Call your caregiver if:

• Your wound gets larger or becomes more red and has pus.
  
  
• You have questions or concerns about your injury, medicine, or care.

When should I seek immediate help?

Seek care immediately or call 911 if:

• You feel dizzy, have a fever, start throwing up, or sweat more than usual.
  
  
• You have chest pain or trouble breathing, or your skin is red, swollen, or more painful.
  
  
• You have joint pains, problems moving the injured part, or get tender lumps in your groin or armpits.
  
  
• You have numbness (no feeling) or tingling in the area of the bite.
  
  
• You have tightness in your throat, wheezing when breathing, swollen tongue, or rashes all over your body.
  
  
• You start bleeding through your nose or other parts of your body.
  
  
• You start passing dark urine or less urine than is usual for you.

Where can I find more information?

Contact any of the following:

• 24-Hour Nationwide Poison Control Hotline
  National Capital Poison Center
  3201 New Mexico Avenue, Suite 310
  Washington , DC 20016
  Phone: 1- 800 - 222-1222
  Web Address: http://www.poison.org
  

• American Academy of Family Physicians
  11400 Tomahawk Creek Parkway
  Leawood , KS 66211-2680
  Phone: 1- 913 - 906-6000
  Phone: 1- 800 - 274-2237
  Web Address: http://www.aafp.org
  

• Centers for Disease Control and Prevention
  1600 Clifton Road
  Atlanta , GA 30333
  Phone: 1- 404 - 6393311
  Phone: 1- 800 - 3113435
  Web Address: http://www.cdc.gov
  

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment.

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The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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