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| | {{Snakebites (Patient information) }} |
| | '''For the WikiDoc page for this topic, click [[Snakebites|here]]''' |
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| | {{CMG}}; {{AE}} {{KD}} |
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| ==Overview== | | ==Overview== |
| | Snake bites occur when a snake bites the skin. They are medical emergencies if the snake is poisonous |
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| A '''snakebite''', or snake bite, is a [[bite]] inflicted by a [[snake]]. Snakes often bite their prey when feeding, but occasionally, they bite humans. People can avoid and treat snakebites by knowing their [[etiology]], along with prevention tips, and first-aid and hospital treatment.
| | ==What are the symptoms of Snakebites?== |
| | Symptoms depend on the type of snake, but may include: |
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| ==Envenomation==
| | * [[Bleeding]] from wound |
| 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.<ref>{{cite journal | author = Russell F | title = When a snake strikes | journal = Emerg Med | volume = 22 | issue = 12 | pages = 33-4, 37-40, 43 | year = 1990}}</ref> Snakes are found on every continent except Antarctica. The most diverse and widely hihpihh
| | * Blurred vision |
| distributed snake family, the [[Colubrid]]s, has only a few members which are harmful to humans. Of the 120 known indigenous snake species in North America, only 20 are venomous to human beings, all belonging to the families [[Viperidae]] and [[Elapidae]].[http://www.fda.gov/fdac/features/995_snakes.html] However, in the [[United States]], every state except [[Maine]], [[Alaska]], and [[Hawaii]] is home to at least one of 20 venomous snake species.[http://www.fda.gov/fdac/features/995_snakes.html]
| | * 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 |
| | * Swelling at the site of the bite |
| | * [[Weakness]] |
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| Since the act of delivering venom is completely voluntary, all venomous snakes are capable of biting without injecting venom into their victim. Such snakes will often deliver such a "dry bite" (about 50% of the time)[http://www.cdc.gov/nasd/docs/d000001-d000100/d000054/d000054.html] rather than waste their venom on a creature too large for them to eat. Some dry bites may also be the result of imprecise timing on the snake's part, as venom may be prematurely released before the fangs have penetrated the victim’s flesh. Even without venom, some snakes, particularly large constrictors such as those belonging to the [[Boidae]] and [[Pythonidae]] families, can deliver damaging bites; large specimens often causing severe [[laceration]]s as the victim or the snake itself pulls away, causing the flesh to be torn by the needle-sharp recurved teeth embedded in the victim. While not normally as life-threatening as a bite from a venomous species, the bite can be at least temporarily debilitating and as mentioned [[#Symptoms|below]], could lead to dangerous infections if improperly dealt with.
| | Rattlesnake bites are painful when they occur. Symptoms usually begin right away and may include: |
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| == Frequency and statistics==
| | * [[Bleeding]] |
| [[Image:Snakebite morbidity map.png|right|300px|thumb|Map showing global distribution of snakebite morbidity.]] | | * Breathing difficulty |
| Since reporting is not mandatory, many snakebites go unreported. Consequently, no accurate study has ever been conducted to determine the frequency of snakebites on the international level. However, some estimates put the number at 2.5 million bites per year, resulting in perhaps 125,000 deaths.[http://www.who.int/bloodproducts/animal_sera/en/] Worldwide, snakebites occur most frequently in the summer season when snakes are active and humans are outdoors.<ref name="WingertChan1988">{{cite journal | author = Wingert W, Chan L | title = Rattlesnake bites in southern California and rationale for recommended treatment | journal = West J Med | volume = 148 | issue = 1 | pages = 37-44 | year = 1988 | id = PMID 3277335|url=http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1026007
| | * Blurred vision |
| |accessdate=2006-05-26}}</ref> [[Agricultural]] and [[tropical]] regions report more snakebites than anywhere else.[http://www.who.int/bloodproducts/animal_sera/en/] Victims are typically male and between 17 and 27 years of age.<ref name="WingertChan1988"/>
| | * Eyelid drooping |
| | * Low blood pressure |
| | * Nausea and vomiting |
| | * Numbness |
| | * Pain at site of bite |
| | * [[Paralysis]] |
| | * Rapid pulse |
| | * Skin color changes |
| | * [[Swelling]] |
| | * Tingling |
| | * Tissue damage |
| | * Thirst |
| | * Tiredness |
| | * [[Weakness]] |
| | * Weak pulse |
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| A late 1950s study estimated that 45,000 snakebites occur each year in the [[United States]].<ref>{{cite journal | author = Parrish H | title = Incidence of treated snakebites in the United States | journal = Public Health Rep | volume = 81 | issue = 3 | pages = 269-76 | year = 1966 | id = PMID 4956000}}</ref> Despite this large number, only 7,000 to 8,000 of those snakebites are actually caused by venomous snakes, resulting in an average of 10 deaths.[http://www.cdc.gov/nasd/docs/d000001-d000100/d000054/d000054.html][http://www.aphis.usda.gov/mrpbs/safety_security/library/snake_bites.pdf] This puts the chance of survival at roughly 499 out of 500. The majority of bites in the United States occur in the southwestern part of the country, in part because [[rattlesnake]] populations in the eastern states are much lower.<ref>Russell, Findlay E. “Snake venom poisoning.” Great Neck, N.Y.: Scholium, 1983:163.</ref>
| | Cottonmouth and copperhead bites are painful right when they occur. Symptoms, which usually begin right away, may include: |
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| Most snakebite related deaths in the [[United States]] are attributed to eastern and western diamondback rattlesnake bites. Children and the elderly are most likely to die (Gold & Wingert 1994). The state of [[North Carolina]] has the highest frequency of reported snakebites, averaging approximately 19 bites per 100,000 persons. The national average is roughly 4 bites per 100,000 persons.<ref>{{cite journal | author = Russell F | title = Snake venom poisoning in the United States | journal = Annu Rev Med | volume = 31 | issue = | pages = 247-59 | year = | id = PMID 6994610}}</ref>
| | * [[Bleeding]] |
| | * Breathing difficulty |
| | * [[Low blood pressure]] |
| | * Nausea and vomiting |
| | * [[Numbness]] and tingling |
| | * Pain at site of bite |
| | * Shock |
| | * Skin color changes |
| | * [[Swelling]] |
| | * Thirst |
| | * Tiredness |
| | * Tissue damage |
| | * Weakness |
| | * [[Weak pulse]] |
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| {| border="1" cellpadding="5" cellspacing="0" class="wikitable"
| | Coral snake bites may be painless at first. Major symptoms may not develop for hours. Do NOT make the mistake of thinking you will be fine if the bite area looks good and you are not in a lot of pain. Untreated coral snake bites can be deadly. Symptoms may include: |
| |+'''Global evaluation of snakebites [http://www.who.int/bloodproducts/publications/en/bulletin_1998_76(5)_515-524.pdf]'''
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| |-
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| ! width="250" style="background:#FFE4C4;" | '''Landmasses'''
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| ! style="background:#FFE4C4;" | Population (x10<sup>6</sup>)
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| ! style="background:#FFE4C4;" | Total number of bites
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| ! style="background:#FFE4C4;" | No. of envenomations
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| ! style="background:#FFE4C4;" | No. of fatalities
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| |-
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| | width=250 | Europe
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| | 730
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| | width=150 | 25,000
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| | 8,000
| |
| | 30
| |
| |-
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| | width=250 | Middle East
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| | 160
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| | width=150 | 20,000
| |
| | 15,000
| |
| | 100
| |
| |-
| |
| | width=250 | USA and Canada
| |
| | 270
| |
| | width=150 | 45,000
| |
| | 6,500
| |
| | 15
| |
| |-
| |
| | width=250 | Central and South America
| |
| | 400
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| | width=150 | 300,000
| |
| | 150,000
| |
| | 5,000
| |
| |-
| |
| | width=250 | Africa
| |
| | 760
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| | width=150 | 1,000,000
| |
| | 500,000
| |
| | 20,000
| |
| |-
| |
| | width=250 | Asia
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| | 3,500
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| | width=150 | 4,000,000
| |
| | 2,000,000
| |
| | 100,000
| |
| |-
| |
| | width=250 | Oceania
| |
| | 20*
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| | width=150 | 10,000
| |
| | 3,000
| |
| | 200
| |
| |-
| |
| | width=250 style="background:#DCDCDC;" |'''Total'''
| |
| | style="background:#DCDCDC;" | 5,840
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| | width=150 style="background:#DCDCDC;" | 5,400,000
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| | style="background:#DCDCDC;" | 2,682,500
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| | style="background:#DCDCDC;" | 125,345
| |
| |}
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| '''*Population at risk'''
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| == Prevention == | | * Blurred vision |
| | * Breathing difficulty |
| | * [[Convulsions]] |
| | * [[Drowsiness]] |
| | * Eyelid drooping |
| | * Headache |
| | * [[Low blood pressure]] |
| | * Mouth watering (excessive salivation) |
| | * [[Nausea]] and [[vomiting]] |
| | * Numbness |
| | * Pain and swelling at site of bite |
| | * [[Paralysis]] |
| | * [[Shock]] |
| | * Slurred speech |
| | * Swallowing difficulty |
| | * Swelling of tongue and throat |
| | * [[Weakness]] |
| | * Skin color changes |
| | * Skin tissue damage |
| | * Stomach or abdominal pain |
| | * Weak pulse |
| | ==What causes Snakebites?== |
| | Poisonous snake bites include bites by any of the following: |
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| Snakes are most likely to bite when they feel threatened, are startled, provoked, and/or have no means of escape when cornered. Encountering a snake is always considered dangerous and it is recommended to leave the vicinity. There is no practical way to safely identify any snake species as appearances vary dramatically, <!--BUT-->see [[#Snake identification|below]].
| | * Cobra |
| | * Copperhead |
| | * Coral snake |
| | * Cottonmouth (water moccasin) |
| | * Rattlesnake |
| | * Various snakes found at zoos |
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| Snakes are likely to approach residential areas when attracted by prey, such as [[rodents]]. Practicing regular [[pest control]] can reduce the threat of snakes considerably. It is beneficial to know the species of snake that are common in home areas, while traveling, or hiking. Areas of the world such as [[Africa]], [[Australia]], [[Neotropics]], and [[southern Asia]] are inhabited by many particularly dangerous snakes species. Being wary of snake presence and ultimately avoiding it when known is strongly recommended.
| | All snakes will bite when threatened or surprised, but most will usually avoid people if possible and only bite as a last resort. |
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| Sturdy over-the-ankle [[boot]]s, loose clothing and responsible behavior offer effective protection from snakebites when in the [[wilderness]]. It is important to tread heavily and cause loud ground noises. The rationale behind this is that the snake will feel the vibrations and flee from the area. However, this generally only applies to [[North America]] as some larger and more aggressive snakes in other parts of the world, such as [[king cobra]]s and [[black mamba]]s, will actually protect their territory. When dealing with direct encounters it is best to remain silent and motionless. If the snake has not yet fled it is important to step away slowly and cautiously.
| | Snakes found in and near water are often mistaken as being poisonous. Most species of snake are harmless and many bites are not life-threatening, but unless you are absolutely sure that you know the species, treat it seriously. |
| | ==When to seek urgent medical care?== |
| | Call 911 or your local emergency number if someone has been bitten by a snake. If possible, call ahead to the emergency room so that antivenom can be ready when the person arrives. |
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| When doing camping activities such as gathering firewood at night, it is important to make use of a [[flashlight]] and avoid walking [[barefoot]]ed. Approximately 85% of the natural snakebites occur below the victims' knees. [http://www.cdc.gov/nasd/docs/d000001-d000100/d000054/d000054.html] Snakes may be unusually active during especially warm nights with ambient temperatures exceeding 70°F, and a person not wearing footwear will have no protection from a potential bite.
| | You may also call the National Poison Control Center (1-800-222-1222). The center can be called from anywhere in the United States. This national hotline number will let you talk to experts in poisoning. They will give you further instructions. |
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| It is advised not to reach blindly into hollow logs, flip over large rocks, and enter old [[Log cabin|cabins]] or other potential snake hiding-places. When [[climbing|rock climbing]], it is not safe to grab ledges or crevices without thoroughly and extensively examining them first, as snakes are [[coldblooded]] creatures and often sunbathe atop rock ledges.
| | This is a free and confidential service. All local poison control centers in the United States use this national number. You should call if you have any questions about poisoning or poison prevention. It does NOT need to be an emergency. You can call for any reason, 24 hours a day, 7 days a week. |
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| Pet owners of domestic animals and/or snakes should be wary that a snake is capable of causing injury and that is necessary to always act with caution — approximately 65%{{vague|see "85%" above}} of snakebites occur to the victims’ hands or fingers. When handling snakes it is never wise to consume [[alcoholic beverage]]s. In the United States more than 40% of snakebite victims intentionally put themselves in harms way by attempting to capture wild snakes or by carelessly handling their dangerous pets — 40% of that number had a [[blood alcohol level]] of 0.1 percent or more.<ref>{{cite journal | author = Kurecki B, Brownlee H | title = Venomous snakebites in the United States | journal = J Fam Pract | volume = 25 | issue = 4 | pages = 386-92 | year = 1987 | id = PMID 3655676}}</ref>
| | ==Treatment options== |
| | '''First Aid''' |
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| It is also important to avoid snakes that appear to be dead, as some species will actually rollover on their backs and stick out their tongue to fool potential threats. A snake's detached head can immediately [[reflex action|reflex]] and potentially bite. The bite can induce just as bad an effect as a live snake bite.<ref>{{cite journal | author = Gold B, Barish R | title = Venomous snakebites. Current concepts in diagnosis, treatment, and management. | journal = Emerg Med Clin North Am | volume = 10 | issue = 2 | pages = 249-67 | year = 1992 | id = PMID 1559468}}</ref>
| | 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. |
| Dead snakes are also incapable of regulating the venom they inject, so a bite from a dead snake can often contain large amounts of venom.
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| == Symptoms ==
| | 2. If you have a pump suction device (such as that made by Sawyer), follow the manufacturer's directions. |
| The most common symptoms of all snakebites are [[panic]], [[fear]] and emotional instability, which may cause symptoms such as [[nausea]] and [[vomiting]], [[diarrhea]], [[vertigo (medical)|vertigo]], [[fainting]], [[tachycardia]], and cold, clammy skin.<ref>{{cite journal | author = Kitchens C, Van Mierop L | title = Envenomation by the Eastern coral snake (Micrurus fulvius fulvius). A study of 39 victims | journal = JAMA | volume = 258 | issue = 12 | pages = 1615-8 | year = 1987 | id = PMID 3625968}}</ref> [[Television]], [[literature]], and [[folklore]] are in part responsible for the hype surrounding snakebites, and a victim may have unwarranted thoughts of imminent death.
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| Dry snakebites, and those inflicted by a non-venomous species, are still able to cause severe injury to the victim. There are several reasons for this; a snakebite which is not treated properly may become [[infected]] (as is often reported by the victims of viper bites whose fangs are capable of inflicting deep puncture wounds), the bite may cause [[anaphylaxis]] in certain people, and the [[saliva]] and fangs of the snake may harbor many dangerous microbial contaminants, including ''[[Clostridium tetani]]''. If neglected, an infection may spread and potentially even kill the victim.
| | 3. Remove any rings or constricting items because the affected area may swell. Create a loose splint to help restrict movement of the area. |
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| Most snakebites, whether by a venomous snake or not, will have some type of local effect. Usually there is minor pain and [[Erythema|redness]], but this varies depending on the site. Bites by [[vipers]] and some cobras may be extremely painful, with the local tissue sometimes becoming tender and severely [[Edema|swollen]] within 5 minutes. This area may also bleed and [[blister]].
| | 4. If the area of the bite begins to swell and change color, the snake was probably poisonous. |
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| Interestingly, bites caused by the [[Mojave Rattlesnake|Mojave rattlesnake]] and the [[speckled rattlesnake]] reportedly cause little or no pain despite being serious injuries. Victims may also describe a “rubbery,” “minty,” or “metallic” taste if bitten by certain species of rattlesnake. [[Spitting cobra]]s and [[Rinkhals]]es can spit venom in their victims’ eyes. This results in immediate pain, vision problems, and sometimes [[blindness]].
| | 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. |
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| Some Australian elapids and most viper [[envenomation]]s will cause [[coagulopathy]], sometimes so severe that a person may bleed spontaneously from the mouth, nose, and even old, seemingly-healed wounds. Internal organs may bleed, including the brain and intestines and will cause [[ecchymosis]] (bruising) of the victim's skin. If the bleeding is left unchecked the victim may die of [[Hypovolemia|blood loss]].
| | 6. Get medical help right away. |
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| Venom emitted from cobras, most [[sea snakes]], mambas, and other elapids contain toxins which attack the [[nervous system]]. The victim may present with strange disturbances to their vision, including blurriness. This is commonly due to the venom [[Paralysis|paralyzing]] the [[ciliary muscle]], which is responsible for focusing the [[Lens (anatomy)|lens]] of the eye, but can be the result of eyelid paralysis as well. Victims will also report [[paresthesia]] throughout their body, as well as difficulty speaking and breathing. Nervous system problems will cause a huge array of symptoms, and those provided here are not exhaustive. In any case, if the victim is not treated immediately they may die from [[respiratory failure]].
| | 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 several hours after it's dead (from a reflex). |
| | '''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. |
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| Venom emitted from some Australian elapids, <!--the [[Daboia|Russell’s viper]], LIKE-->almost all vipers, and all sea snakes causes [[necrosis]] of muscle tissue. Muscle tissue may begin to die throughout the body, a condition known as [[rhabdomyolysis]]. Dead muscle cells may even clog the kidney which filters out proteins. This, coupled with hypotension, can lead to [[kidney failure]], and, if left untreated, eventually death.
| | ==Where to find medical care for Snakebites?== |
| | [http://maps.google.com/maps?q={{urlencode:{{#if:{{{1|}}}|{{{1}}}|map+top+hospital+Condition}}}}&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&sa=N&hl=en&tab=wl Directions to Hospitals Treating Snakebites] |
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| ==Treatment== | | ==Prevention== |
| It is not an easy task determining whether or not a bite by any species of snake is life-threatening. A bite by a North American [[Agkistrodon contortrix|copperhead]] on the ankle is usually a moderate injury to a healthy adult, but a bite to a child’s abdomen or face by the same snake may well be fatal. The outcome of all snakebites depends on a multitude of factors; the size, physical condition, and temperature of the snake, the age and physical condition of the victim, the area and tissue bitten (e.g., foot, torso, vein or muscle, etc.), the amount of venom injected, the time it takes for the patient to find treatment, and finally the quality of that treatment.
| | * 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 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. |
| | * 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. |
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| ===WebMD Information=== | | ==Sources== |
| Consult a physician or Poison Control Center. This information is not intended to be medical advice.
| | http://www.nlm.nih.gov/medlineplus/ency/article/000031.htm |
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| *Remove all jewelry.
| | [[Category:Patient information]] |
| *Wash the snakebite with soap and water.
| | [[Category:Emergency medicine]] |
| *Apply suction using an extractor device without incising the wound if less than 15 minutes have elapsed from the initial bite and the person who has been bitten is more than 1 hour from medical attention.
| | [[Category:Toxicology]] |
| *Apply a constricting band above the bite if less than 30 minutes have passed from the initial bite. Wrap the band tight enough to slow circulation but not to stop pulses. Use the pressure immobilization technique.
| | [[Category:Intensive care medicine]] |
| *Immobilize the limb below the heart.
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| *Cool the limb for pain control, but do not apply ice directly to the wound.
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| *Give 100% oxygen, if available.
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| *Perform cardiopulmonary resuscitation (CPR) if necessary.
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| ===Snake identification===
| | {{WH}} |
| Identification of the snake is important in planning treatment in certain areas of the world, but is not always possible. Ideally the dead snake would be brought in with the patient, but in areas where snake bite is more common, local knowledge may be sufficient to recognize the snake.
| | {{WS}} |
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| In countries where polyvalent antivenins are available, such as North America, identification of snake is not of much significance.
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| The three types of venomous snakes that cause the majority of major clinical problems are the [[viper]], [[krait]] and [[cobra]]. Knowledge of what species are present locally can be crucially important, as is knowledge of typical signs and symptoms of envenoming by each species of snake.
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| A scoring systems can be used to try and determine biting snake based on clinical features,<ref> {{cite journal | author = Pathmeswaran A, Kasturiratne A, Fonseka M, Nandasena S, Lalloo D, de Silva H | title = Identifying the biting species in snakebite by clinical features: an epidemiological tool for community surveys | journal = Trans R Soc Trop Med Hyg | volume = 100 | issue = 9 | pages = 874-8 | year = 2006 | id = PMID 16412486}} </ref> but these scoring systems are extremely specific to a particular geographical area.
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| ===First Aid===
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| Snakebite [[first aid]] recommendations vary, in part because different snakes have different types of venom. Some have little local effect, but life-threatening systemic effects, in which case containing the venom in the region of the bite (e.g., by pressure immobilization) is highly desirable. Other venoms instigate localized tissue damage around the bitten area, and immobilization may increase the severity of the damage in this area, but also reduce the total area affected; whether this trade-off is desirable remains a point of controversy.
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| Because snakes vary from one country to another, first aid methods also vary; treatment methods suited for rattlesnake bite in the United States might well be fatal if applied to a [[tiger snake]] bite in Australia. As always, this article is not a legitimate substitute for professional medical advice. Readers are strongly advised to obtain guidelines from a reputable first aid organization in their own region, and to beware of homegrown or anecdotal remedies.
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| However, most first aid guidelines agree on the following:
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| #Protect the patient (and others, including yourself) from further bites. While identifying the species is desirable in certain regions, do not risk further bites or delay proper medical treatment by attempting to capture or kill the snake. If the snake has not already fled, carefully remove the patient from the immediate area.
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| #Keep the patient calm and [[call for help]] to arrange for transport to the nearest hospital [[emergency room]], where [[antivenin]] for snakes common to the area will often be available.
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| #Make sure to keep the bitten limb in a functional position and below the victim's heart level so as to minimize blood returning to the heart and other organs of the body.
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| #Do not give the patient anything to eat or drink. This is especially important with consumable alcohol, a known [[vasodilator]] which will speedup the absorption of venom. Do not administer [[stimulant]]s or [[Analgesics|pain medications]] to the victim, unless specifically directed to do so by a [[physician]].
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| #Remove any items or clothing which may constrict the bitten limb if it swells (rings, bracelets, watches, footwear, etc.)
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| #Keep the patient as still as possible.
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| #Do not incise the bitten site.
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| Many organizations, including the American Medical Association and American Red Cross, recommend washing the bite with soap and water. However, do not attempt to clean the area with any type of chemical.
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| note: Treatment for [http://www.usyd.edu.au/anaes/venom/snakebite.html Australian snake bites] (which may differ to other areas of the world) stringently recommends against cleaning the wound. Traces of venom left on the skin/bandages from the strike can be used in combination with a snake bite identification kit to identify the species of snake. This speeds determination of which antivenin to administer in the emergency room.
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| ===Pressure immobilization===
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| Pressure immobilization is not appropriate for cytotoxic bites such as those of most [[Viperidae|vipers]],<ref>{{cite journal | author = Rogers I, Celenza T | title = Simulated field experience in the use of the Sam splint for pressure immobilization of snakebite | journal = Wilderness Environ Med | volume = 13 | issue = 2 | pages = 184-5 | year = 2002 |url=http://www.wemjournal.org/wmsonline/?request=get-document&issn=1080-6032&volume=013&issue=02&page=0184| id = PMID 12092977}}</ref><ref>{{cite journal | author = Bush S, Green S, Laack T, Hayes W, Cardwell M, Tanen D | title = Pressure immobilization delays mortality and increases intracompartmental pressure after artificial intramuscular rattlesnake envenomation in a porcine model | journal = Ann Emerg Med | volume = 44 | issue = 6 | pages = 599-604 | year = 2004 | id = PMID 15573035|url=http://www.llu.edu/llu/faculty/whayes/documents/2004_bush_et_al._pressure-immob.pdf|accessdate=2006-06-25}}</ref><ref>{{cite journal | author = Sutherland S, Coulter A | title = Early management of bites by the eastern diamondback rattlesnake (Crotalus adamanteus): studies in monkeys (Macaca fascicularis) | journal = Am J Trop Med Hyg | volume = 30 | issue = 2 | pages = 497-500 | year = 1981 | id = PMID 7235137|url=http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7235137
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| |accessdate=2005-06-25}}</ref> but is highly effective against neurotoxic venoms such as those of most [[elapid]]s.<ref>{{cite journal | author = Rogers I, Winkel K | title = Struan Sutherland's "Rationalisation of first-aid measures for elapid snakebite"--a commentary. | journal = Wilderness Environ Med | volume = 16 | issue = 3 | pages = 160-3 | year = 2005 | id = PMID 16209471|url=http://www.wemjournal.org/wmsonline/?request=get-document&issn=1080-6032&volume=016&issue=03&page=0160
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| |accessdate=2006-06-25}}</ref><ref> {{cite journal | author = Sutherland S | title = Deaths from snake bite in Australia, 1981-1991 | journal = Med J Aust | volume = 157 | issue = 11-12 | pages = 740-6 | year = | id = PMID 1453996}}</ref><ref>
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| {{cite journal | author = Sutherland S, Leonard R | title = Snakebite deaths in Australia 1992-1994 and a management update | journal = Med J Aust | volume = 163 | issue = 11-12 | pages = 616-8 | year = | id = PMID 8538559}}</ref> Developed by [[Struan Sutherland]] in [[1978]],<ref>{{cite journal | author = Sutherland S, Coulter A, Harris R | title = Rationalisation of first-aid measures for elapid snakebite | journal = Lancet | volume = 1 | issue = 8109 | pages = 183-5 | year = 1979 | id = PMID 84206|url=http://www.wemjournal.org/wmsonline/?request=get-document&issn=1080-6032&volume=016&issue=03&page=0164}}</ref> the object of pressure immobilization is to contain venom within a bitten limb and prevent it from moving through the [[Lymphatic system#Lymphatic circulation|lymphatic system]] to the vital organs in the body core. This therapy has two components: pressure to prevent lymphatic drainage, and immobilization of the bitten limb to prevent the pumping action of the [[skeletal muscle]]s. Pressure is preferably applied with an elastic bandage, but any cloth will do in an emergency. Bandaging begins two to four inches above the bite (i.e. between the bite and the heart), winding around in overlapping turns and moving up towards the heart, then back down over the bite and past it towards the hand or foot. Then the limb must be held immobile: not used, and if possible held with a splint or sling. The bandage should be about as tight as when strapping a sprained ankle. It must ''not'' cut off blood flow, or even be uncomfortable; if it is uncomfortable, the patient will unconsciously flex the limb, defeating the immobilization portion of the therapy. The location of the bite should be clearly marked on the outside of the bandages. Some peripheral [[edema]] is an expected consequence of this process.
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| Apply pressure immobilization as quickly as possible; if you wait until symptoms become noticeable you will have missed the best time for treatment. Once a pressure bandage has been applied, it should ''not'' be removed until the patient has reached a medical professional. The combination of pressure and immobilization can contain venom so effectively that no symptoms are visible for more than twenty-four hours, giving the illusion of a dry bite. But this is only a delay; removing the bandage releases that venom into the patient's system with rapid and possibly fatal consequences.
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| ===Outmoded treatments===
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| The following treatments have all been recommended at one time or another, '''but are now considered to be ineffective or outright dangerous, and should not be used under any circumstances'''. Many cases in which such treatments appear to work are in fact the result of dry bites.
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| [[Image:Snakebite kit.jpg|230px|thumb|Old style snake bite kit that should not be used.]]
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| *Application of a [[tourniquet]] to the bitten limb is not recommended since reducing or cutting off circulation can lead to tissue death in the area.
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| *Cutting open the bitten area often used prior to suction is not recommended (see also below) since it causes damage and increases the risk of infection.
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| *Sucking out venom, either by mouth or with a pump does not work and may harm the affected area directly.<ref name="pmid16781926">
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| {{cite journal |author=Holstege CP, Singletary EM |title=Images in emergency medicine. Skin damage following application of suction device for snakebite |journal=Annals of emergency medicine |volume=48 |issue=1 |pages=105, 113 |year=2006 |pmid=16781926 |doi=10.1016/j.annemergmed.2005.12.019}}
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| </ref> Suction started after 3 minutes removes a clinically insignificant quantity - less than one thousandth of the venom injected - as shown in a human study.<ref>
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| {{cite journal | author = Alberts M, Shalit M, LoGalbo F | title = Suction for venomous snakebite: a study of "mock venom" extraction in a human model | journal = Ann Emerg Med | volume = 43 | issue = 2 | pages = 181-6 | year = 2004 | id = PMID 14747805}}
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| </ref> In a study with pigs, suction not only caused no improvement but led to necrosis in the suctioned area.<ref name="pmid11055564">
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| {{cite journal |author=Bush SP, Hegewald KG, Green SM, Cardwell MD, Hayes WK |title=Effects of a negative pressure venom extraction device (Extractor) on local tissue injury after artificial rattlesnake envenomation in a porcine model |journal=Wilderness & environmental medicine |volume=11 |issue=3 |pages=180–8 |year=2000 |pmid=11055564 |doi=}}
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| </ref> Suctioning by mouth presents a risk of further poisoning through the mouth's mucous tissues.<ref>
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| Riggs BS, Smilkstein MJ, Kulig KW, ''et al.'' Rattlesnake envenomation with massive oropharyngeal edema following incision and suction (Abstract). Presented at the AACT/AAPCC/ABMT/CAPCC Annual Scientific Meeting, Vancouver, Canada, September 27-October 2, 1987.
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| </ref> The well-meaning family member or friend may also release bacteria into the victim’s wound, leading to infection.
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| *Immersion in warm water or sour milk, followed by the application of [[Snake-Stones]] (also known as Black Stones or la Pierre Noire), which are believed to draw off the poison in much the way a sponge soaks up water.
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| *Application of [[potassium permanganate]].
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| *Use of [[electroshock therapy]]. Although still advocated by some, animal testing has shown this treatment to be useless and potentially dangerous.<ref>
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| {{cite journal | author = Russell F | title = Another warning about electric shock for snakebite | journal = Postgrad Med | volume = 82 | issue = 5 | pages = 32 | year = 1987 | id = PMID 3671201}}</ref><ref>
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| {{cite journal | author = Ryan A | title = Don't use electric shock for snakebite | journal = Postgrad Med | volume = 82 | issue = 2 | pages = 42 | year = 1987 | id = PMID 3497394}}</ref><ref>
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| {{cite journal | author = Howe N, Meisenheimer J | title = Electric shock does not save snakebitten rats | journal = Ann Emerg Med | volume = 17 | issue = 3 | pages = 254-6 | year = 1988 | id = PMID 3257850}}</ref><ref>
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| {{cite journal | author = Johnson E, Kardong K, Mackessy S | title = Electric shocks are ineffective in treatment of lethal effects of rattlesnake envenomation in mice. | journal = Toxicon | volume = 25 | issue = 12 | pages = 1347-9 | year = 1987 | id = PMID 3438923}}</ref>
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| In extreme cases, where the victims were in remote areas, all of these misguided attempts at treatment have resulted in injuries far worse than an otherwise mild to moderate snakebite. In worst case scenarios, thoroughly constricting tourniquets have been applied to bitten limbs, thus completely shutting off blood flow to the area. By the time the victims finally reached appropriate medical facilities their limbs had to be [[amputated]].
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| ==See also==
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| * [[Snake]]
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| * [[Venomous snakes]]
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| * [[Snake venom]]
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| * [[Snake-Stones]]
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| * [[Antivenin]]
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| * [[Medical emergency]]
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| * [[Wilderness first aid]]
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| * [[Wilderness emergency medical technician]]
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| == Footnotes ==
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| {{reflist|2}}
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| == References ==
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| * {{cite paper
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| |author=Palm Beach Herpetological Society|url=http://agecon.uwyo.edu/riskmgt/humanrisk/VenomousSnakeBite.pdf
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| |title=Venomous Snake Bite"
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| |accessdate=2006-06-26}}
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| * Sullivan JB, Wingert WA, Norris Jr RL. ''North American Venomous Reptile Bites. Wilderness Medicine: Management of Wilderness and Environmental Emergencies'', 1995; 3: 680-709.
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| * U.S. Food and Drug Administration (November 2002) [http://www.fda.gov/fdac/features/995_snakes.html "For Goodness Snakes! Treating and Preventing Venomous Bites"]. Retrieved December 30, 2005.
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| * World Health Organization. [http://www.who.int/bloodproducts/animal_sera/en/ "Animal sera"]. Retrieved December 30, 2005.
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| ==External links==
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| * [http://www.bt.cdc.gov/disasters/snakebite.asp US Center for Disease Control (CDC) fact sheet on snake bites] - also Español, Tieng Viet (Vietnamese)
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| * [http://www.wildernessutah.com/brain/snakebites.html Wilderness Utah] - J. Jones, MD; Dispelling The Snakebite Myth
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| * [http://www.health-care-clinic.org/diseases/snakebite.html First Aid for Snake Bites]
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| * [http://www.emedicine.com/emerg/ENVIRONMENTAL.htm Snake envonomation treatment]
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| * [http://www.survivaliq.com/survival/poisonous-snakes-and-lizards.htm Poisonous snakes and lizards]
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| * [http://www.rattlesnakebite.org Firsthand account of a snakebite] (with graphic photos of victim's hand through multiple stages of surgery)
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| *[http://www.venomousreptiles.org/articles/72 Victim's account of rattlesnake bite - Crotalus atrox] (includes graphic photos of wound)
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| *[http://www.venomousreptiles.org/articles/95 Wife's account of the same Crotalus atrox bite]
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| *[http://www.venomousreptiles.org/articles/305 Victim's account of rattlesnake bite - Crotalus scutulatus]
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| *[http://www.venomousreptiles.org/articles/345 Victim's account of rattlesnake bite - Crotalus horridus] (includes graphic photo of wound)
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| * [http://www.snakebitenews.com/ SnakeBiteNews.com]. Accessed [[27 October]] [[2006]].
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| * [http://www.venom-center.com/ Venomous Snakes Information Community]
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| * [http://thesnakebite.tv/ TheSnakeBite.tv] - Attack videos and information collection
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| * [http://www.CrotalusandCompany.com/ Crotalus & Company] Venomous Snake Breeder
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| * [http://southamptonalumni.com/freeware101/snakebite U.S. Army pamphlet on snakebite symptoms and first aid]. Accessed [[15 May]] [[2007]].
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| [[Category:Snakes]]
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