http://news.yahoo.com/man-survives-snake-bite-wash-zoos-antivenin-004609479.html
This article and the rattler under a chair at DRV are a reminder that we need to be aware of venomous snakes/insects when we are travelling.
Dave posted this on another forum a while back. With so much conflicting info and "snake bite" kits sold at stores, I thought it was good info...good enough that I printed it out, include it in my first aid kit.
Excerpt from our US Navy Corpsman Field Medicine Manual circa 2008
TERMINAL LEARNING OBJECTIVES
1. Given an envenomation casualty, in a combat environment, and standard field medical equipment and supplies, manage envenomation injuries, to prevent further injury or death. (FMST 04.05)
ENABLING LEARNING OBJECTIVES
1. Without the aid of references, given a list of symptoms, identify the type of venomous snake, per the student handout. (FMST 04.05a)
2. Without the aid of references, given a list of symptoms, identify the type of arthropods, per the student handout. (FMST 04.05b)
3. Without the aid of references, given an envenomation casualty, identify the appropriate treatment, per the student handout. (FMST 04.05c)
1. OVERVIEW
a. Envenomation - An injury or illness caused by the poisonous secretion of an animal, such as a snake, spider, or scorpion, usually transmitted by a bite or sting.
b. Mortality rates - Of all the deaths that occur annually due to envenomation injuries, the majority are caused primarily by insects followed by snakes, then spiders.
2. CLASSIFICATIONS OF POISONOUS SNAKES
a. Crotalidae Family (Pit Vipers)
(1) Characteristics:
(a)Retractable fangs
(b)Heat sensing pit located below the nostril
(c)Large triangular shaped head (in relation to their body)
(2) Examples of Pit Vipers:
(a)Rattlesnakes- Found in the New World only, from the U.S. through Central and South America
(b)Saw-Scaled Viper- Found from Pakistan, throughout the Mid East to Africa (See fig. 2)
(c)Cottonmouth (Water Moccasin, Pilot Snake)- Found throughout Southern and Eastern U. S. (See fig. 3)
(d)Copperhead (Upland Moccasin)- Found in the eastern U. S.
(e)Habu- Found throughout Southeast Asia, including Okinawa
b. Elapidae Family
(1) Characteristics:
(a)Fixed Fangs
(b)Round pupils
(c)Head width is proportionate to body size
(2)Examples
(a)Coral Snakes- Found throughout Southern U.S. to South America, and parts of Asia (See fig. 4)
(b)Cobra –Found from South Asia through Mid East and North Africa (See fig. 5)
(c)Krait- Found throughout South Asia including Pakistan (See fig. 6)
c. Hydrophidae (Sea Snakes)(See fig. 7)
(1)Characteristics:
(a)Fixed fangs
(b)Flat tail
(c)Most are brightly colored (except the Olive Sea Snake)
(2) Example - For medical purposes, size, location and species are irrelevant. Determination of species is too difficult and dangerous to matter. Sea snakes are found throughout the world but mostly in the southern Pacific and Indian ocean. Some are found in estuaries.
d. Colubridae (Most Colubridae are not poisonous)
(1) Characteristics:
(a)Fixed fangs in rear of mouth
(b)Large eyes and small pointed head
(2) Example of venomous Colubridae:
(a) Boomslang- Found throughout the African Savannah
3. ACTIONS OF SNAKE VENOM
a. Snake venoms are chemically complex mixtures of proteins, which have mostly enzymatic properties. The quantity, lethality, and composition vary with the species and the age of the snake, the geographic location, and the time of the year. Venom is highly stable and is resistant to temperature changes, drying, and drugs.
(1) Hemotoxin - Destruction of the capillary cells with resultant leakage
(2) Neurotoxin - Has a paralytic effect
b. Snake venom may include elements that produce both of these effects
4. DIAGNOSING A SNAKE BITE
a. Fang Marks - Fang marks may be present as one or more well defined punctures, or as a series of small lacerations or scratches, or there may not be any noticeable or obvious markings where the bite occurred. The absence of fang marks does not exclude the possibility of envenomation (especially if a juvenile snake is involved). However with rattlesnake envenomation, fang marks are invariably present and are generally seen on close examination. Bleeding may persist from the fang wounds. The presence of fang marks does not always indicate envenomation; rattlesnakes when striking in defense will frequently elect not to inject venom with the bite, resulting in a “dry bite.” Manifestations of signs and sypmtoms of envenomation are necessary to confirm diagnosis of a snake venom poisoning.
b. Signs and Symptoms:
(1) Crotalidae Bite: Symptoms vary depending on the type of snake, and the amount of venom deposited, i.e. younger rattlesnakes tend to dispense all of their venom in relation to a larger, older rattlesnake dispensing either none or a larger amount. Death may occur within 24-48 hours if left untreated. Even with treatment, there is the possibility of loss of effected extremity or a portion of it.
(a)Excruciating pain at the site of the bite.
(b)Presence of fang marks.
(c)Tissue swelling at the site of the bite. Swelling begins within 3 minutes and may continue for up to an hour with enough severity to break the skin.
(d)Severe headache and thirst.
(e)Bleeding from major organs that may appear as hematuria.
(f)Destruction of blood cells and other tissue cells. Discoloration of surrounding tissue.
(g)Tingling or numbness of face and scalp
(h)Muscle fasciculation
c. Elapidae and Colubridae Bite:
(1) Impairment of circulation
(a)Irregular heartbeat
(b)Hypotension
(c)Weakness and exhaustion
(d)Circulatory system collapse
(e)Lowered blood pressure
(2) Severe headache, dizziness, blurred vision, hearing difficulty, confusion and unconsciousness
(3)Nausea, vomiting and diarrhea
(4)Chills and rapid onset of fever
(5)Muscular incoordination and twitching
(6)Excessive perspiration
(7)Respiratory difficulty leading to respiratory arrest
d. Hydrophidae Bite:
(1)Stiffness, muscle aches and spasms of the jaw.
(2)Moderate to severe pain to the effected limb.
(3)Blurred vision and drowsiness.
(4)Respiratory paralysis.
e. Persistent myths about sea snakes include the mistaken idea that they cannot bite effectively. The truth is that though their teeth are small; about 2.5 mm, they are adequate to penetrate skin and they can open their mouths wide enough to bite a person’s thigh. Envenomation from sea snakes is rare, due in most part to their temperament, but does occur. Without treatment, death from sea snake envenomation can occur within 12-24 hours.
5.TREATMENT OF A SNAKE BITE
a.Most definitive care for snake envenomation is anti-venom.
b.Keep the victim calm and reassured. If possible, allow the limb to rest at a neutral level in relation to the victim’s heart.
c.Locate the bite site
d.If the bite is on the hands or feet, immediately remove any rings, bracelets, watches or any constricting items from the extremity.
e.Wrap leg or arm rapidly with 3” to 6” ACE bandage past the knee or elbow joint to immobilize it. Leave the fang marks open.
f.Apply a splint
g.Check distal pulses
h.Monitor and evacuate ASAP
i. COMMON DON’TS
(1)DO NOT cut or incise the bite site
(2)DO NOT apply ice or heat to the bite site.
(3)DO NOT apply oral (mouth) suction.
(4)DO NOT remove dressings/elastic wraps.
(5)DO NOT try to kill the snake for identification as this may lead to other people being bitten.
(6)DO NOT have the victim eat or drink anything.
6. PREVENTION OF SNAKE BITES
a. LEAVE THE SNAKE ALONE!! - This is the best way to avoid snakebite. Most snakes will only bite if threatened. Most snake bites occur when the victim is attempting to catch, kill or play with a snake. Keep hands out of areas that you cannot see (i.e. holes, under rocks and under logs).
7. ARTHROPOD ENVENOMATION
a. Bees, Wasps and Ant Stings- Most of this group sting their victims. Their primary effect is from the strong histamine reaction they cause.
(1) Signs and Symptoms:
(a)Bee/Wasp stings – Honey bees only sting once and leave the stingers and venom sac embedded in the skin. Wasps, hornets, and bumble bees can sting multiple times.
1.Pain
2.Itching/burning sensation
3.Wheal – Raised, inflame skin
4.If patient is allergic, monitor for anaphylactic reaction
(b) Ant sting - Some species of ants, especially the fire ant, can bite and sting repeatedly.
1.Pain
2.Itching/burning sensation
3.Vesicles
4.If patient is allergic, monitor for anaphylactic reaction
5.Multiple bites – can produce the following symptoms:
a.Vomitting
b.Diarrhea
c.Generalized edema
d.Hypotension – due to vasodilation
e.Dysuria
(2) Treatment:
(a) Stingers should be removed immediately to prevent more venom from entering the victim.
1.Remove the stinger by scraping across the skin with a knife blade, ID card or similar object. Grasping the stinger with tweezers only injects the remaining venom into the victim.
(b)Apply ice to the affected area
(c)Apply Hydrocortisone Cream 1% to affected area BID (twice a day)
(d)For anaphylaxis:
1.Benadryl injectable 50mg SQ
2.Epinephrine 0.3-0.5mg 1:1000 SQ
(3) Prevention:
(a)Leave them alone
(b)Avoid nesting sites
(c)Personnel with known allergies should carry an Epi-Pen or Ana-kit
b. Centipedes, Millipedes, and Caterpillars
(1) Signs and symptoms:
(a) Millipedes - Millipedes secrete a toxin on their skin
(1)Itching
(2)Burning
(b) Centipedes - Caused by a bite:
(1)Immediate severe pain
(2)Redness
(3)Swelling
(4)Necrosis and ulceration may sometimes occur
(c) Caterpillars - Some caterpillars have venom in hollow hairs all over their bodies.
(1)Severe burning
(2)Pain
(3)Redness
(4)Swelling
(5)Necrosis
(2) Treatment:
(a)Similar to that of a bee sting. Focus mainly on anaphylactic reaction.
(b)For millipedes, wash skin with soap and water to remove secretions.
(c)For caterpillars, use scotch tape to remove hairs from skin. Do not rub area.
(3) Prevention:
(a)Leave them alone
(b)Avoid known nesting sites and hives
(c)Shake out sleeping bags and clothing and check boots before putting them on.
c. Spider Envenomation:
(1)Black Widow Spider - Only the female bites and has a neurotoxic venom
(a)Description – Glossy black with a red hourglass on the underside of the abdomen. Other species of widow spiders include Brown and Red Widows. All are poisonous and all have a red hourglass pattern on abdomen.
(b) Signs and Symptoms:
1.Initial pain is not severe, but severe local pain rapidly develops
2.The pain gradually spreads over the entire body and settles in the abdomen and legs
3.Weakness
4.Sweating
5.Excessive salivation
6.Rash may occur
7.Tremors
8.Nausea
9.Vomiting
10. Respiratory muscle weakness combined with pain may lead to respiratory arrest
11. Anaphylactic reactions can occur, but are rare
12. Symptoms usually regress after several hours and are usually gone in a few days
(c) Treatment:
1.Clean site with soap and water
2.Intermittent ice for 30 minutes each hour
3.Supportive care
4.Antibiotics if infection occurs
(2) Brown Recluse Spider - Venom is cytotoxic. (Necrotic in nature)
(a) Description- They are small, light brown, and have a dark brown violindesign on the top of their thorax.
(b) Signs and symptoms
1.Painless bite. Most often, the victim does not know they have been bitten.
2.A painful red area with a cyanotic center appears after a few hours.
3.A macular rash (a discolored area of skin that is not raised above the surface) may occur.
4.After 2 or 3 days, there is an area of discoloration that does not blanch with pressure.
5.After a week or two, the area turns dark and the scab falls off leaving an ulcer.
6.After this happens, secondary infection and regional lymphadenopathy occur.
7.The ulcer will persist for weeks or months.
8.In many cases a systemic reaction may occur that is serious and may lead to death.
9.The systemic reactions occur mainly in children and include fever, chills, joint pain, splenomegaly, vomiting, and a generalized rash. These reactions may occur at any time that the ulcer is present.
(c) Treatment:
1.Cold compresses intermittently for the first four (4) days
2.Apply bacitracin
3.It is necessary to excise all the indurated (hardened) skin and fascia before healing will begin.
4.If the ulcer is not excised, it will continue to grow until it is several inches in diameter.
5.Provide supportive care as necessary.
6.Tetanus prophylaxis and antibiotics are necessary to control secondary infection.
7.Anaphylactic reactions may occur.
d. Scorpion Envenomation:
(1) Description - These arthropods inhabit temperate climates around the world and number greater than 650 species. Fifty species can cause serious injury.
(a) The most dangerous scorpions in the U.S. inhabit Arizona and portions of California, Texas, and New Mexico. Although the size and shape of these arthropods can be both intimidating and frightening, envenomation, although potentially painful, very rarely produces mortality in humans.
(2) Signs and Symptoms:
(a)Erythema
(b)Edema
(c)Local pain and or paresthesia (an abnormal touch sensation such as burning or prickling often in the absence of external stimulas) at site of sting.
(d)Pain or paresthesia remote from the site of sting in addition to local
findings.
(e)Cranial nerve dysfunction - Blurred vision, wandering eye movements,
hypersalivation, trouble swallowing, tongue twitching/spasms,
problems with upper airway, slurred speech.
(f)Somatic skeletal neuromuscular dysfunction - Jerking of extremity(ies), restlesness, severe involuntary shaking and jerking that may be mistaken for a siezure.
(3) Diagnosis:
(a) Positive “Tap Test”: excruciating pain when tapping on the affected area. This is the only true way to diagnose a scorpion sting.
(4) Treatment:
(a)Based on the level of envenomation
(b)ABC’s
(c)Ice applied to the site for 30 minutes each hour until symptoms subside
(d)Oral analgesics
(5) Prevention:
(a)Wear shoes
(b)When in the field, bedclothes, sleeping bags, and shoes should be shaken out prior to use
(c)Many scorpions inhabit brush and debris piles in search of its prey. If one is coming in contact with this type of material, it is wise to wear gloves.
(d)Remove wood and rubbish piles around camp
(e)Cracks and recesses in rural desert dwellings should be filled
REFERENCES
Tropical Medicine (7th ed.), Pgs 877-888
Wilderness Medicine (3rd ed.), Ch 28, pgs 680-884, 704-705; Ch 31, pgs 743-768
Hospital Corpsman NAVEDTRA 14295, Pgs 5-12
Poisonous Snakes of the World, NAVMED P-5099 Pgs 83, 107, and 117
This article and the rattler under a chair at DRV are a reminder that we need to be aware of venomous snakes/insects when we are travelling.
Dave posted this on another forum a while back. With so much conflicting info and "snake bite" kits sold at stores, I thought it was good info...good enough that I printed it out, include it in my first aid kit.
Excerpt from our US Navy Corpsman Field Medicine Manual circa 2008
TERMINAL LEARNING OBJECTIVES
1. Given an envenomation casualty, in a combat environment, and standard field medical equipment and supplies, manage envenomation injuries, to prevent further injury or death. (FMST 04.05)
ENABLING LEARNING OBJECTIVES
1. Without the aid of references, given a list of symptoms, identify the type of venomous snake, per the student handout. (FMST 04.05a)
2. Without the aid of references, given a list of symptoms, identify the type of arthropods, per the student handout. (FMST 04.05b)
3. Without the aid of references, given an envenomation casualty, identify the appropriate treatment, per the student handout. (FMST 04.05c)
1. OVERVIEW
a. Envenomation - An injury or illness caused by the poisonous secretion of an animal, such as a snake, spider, or scorpion, usually transmitted by a bite or sting.
b. Mortality rates - Of all the deaths that occur annually due to envenomation injuries, the majority are caused primarily by insects followed by snakes, then spiders.
2. CLASSIFICATIONS OF POISONOUS SNAKES
a. Crotalidae Family (Pit Vipers)
(1) Characteristics:
(a)Retractable fangs
(b)Heat sensing pit located below the nostril
(c)Large triangular shaped head (in relation to their body)
(2) Examples of Pit Vipers:
(a)Rattlesnakes- Found in the New World only, from the U.S. through Central and South America
(b)Saw-Scaled Viper- Found from Pakistan, throughout the Mid East to Africa (See fig. 2)
(c)Cottonmouth (Water Moccasin, Pilot Snake)- Found throughout Southern and Eastern U. S. (See fig. 3)
(d)Copperhead (Upland Moccasin)- Found in the eastern U. S.
(e)Habu- Found throughout Southeast Asia, including Okinawa
b. Elapidae Family
(1) Characteristics:
(a)Fixed Fangs
(b)Round pupils
(c)Head width is proportionate to body size
(2)Examples
(a)Coral Snakes- Found throughout Southern U.S. to South America, and parts of Asia (See fig. 4)
(b)Cobra –Found from South Asia through Mid East and North Africa (See fig. 5)
(c)Krait- Found throughout South Asia including Pakistan (See fig. 6)
c. Hydrophidae (Sea Snakes)(See fig. 7)
(1)Characteristics:
(a)Fixed fangs
(b)Flat tail
(c)Most are brightly colored (except the Olive Sea Snake)
(2) Example - For medical purposes, size, location and species are irrelevant. Determination of species is too difficult and dangerous to matter. Sea snakes are found throughout the world but mostly in the southern Pacific and Indian ocean. Some are found in estuaries.
d. Colubridae (Most Colubridae are not poisonous)
(1) Characteristics:
(a)Fixed fangs in rear of mouth
(b)Large eyes and small pointed head
(2) Example of venomous Colubridae:
(a) Boomslang- Found throughout the African Savannah
3. ACTIONS OF SNAKE VENOM
a. Snake venoms are chemically complex mixtures of proteins, which have mostly enzymatic properties. The quantity, lethality, and composition vary with the species and the age of the snake, the geographic location, and the time of the year. Venom is highly stable and is resistant to temperature changes, drying, and drugs.
(1) Hemotoxin - Destruction of the capillary cells with resultant leakage
(2) Neurotoxin - Has a paralytic effect
b. Snake venom may include elements that produce both of these effects
4. DIAGNOSING A SNAKE BITE
a. Fang Marks - Fang marks may be present as one or more well defined punctures, or as a series of small lacerations or scratches, or there may not be any noticeable or obvious markings where the bite occurred. The absence of fang marks does not exclude the possibility of envenomation (especially if a juvenile snake is involved). However with rattlesnake envenomation, fang marks are invariably present and are generally seen on close examination. Bleeding may persist from the fang wounds. The presence of fang marks does not always indicate envenomation; rattlesnakes when striking in defense will frequently elect not to inject venom with the bite, resulting in a “dry bite.” Manifestations of signs and sypmtoms of envenomation are necessary to confirm diagnosis of a snake venom poisoning.
b. Signs and Symptoms:
(1) Crotalidae Bite: Symptoms vary depending on the type of snake, and the amount of venom deposited, i.e. younger rattlesnakes tend to dispense all of their venom in relation to a larger, older rattlesnake dispensing either none or a larger amount. Death may occur within 24-48 hours if left untreated. Even with treatment, there is the possibility of loss of effected extremity or a portion of it.
(a)Excruciating pain at the site of the bite.
(b)Presence of fang marks.
(c)Tissue swelling at the site of the bite. Swelling begins within 3 minutes and may continue for up to an hour with enough severity to break the skin.
(d)Severe headache and thirst.
(e)Bleeding from major organs that may appear as hematuria.
(f)Destruction of blood cells and other tissue cells. Discoloration of surrounding tissue.
(g)Tingling or numbness of face and scalp
(h)Muscle fasciculation
c. Elapidae and Colubridae Bite:
(1) Impairment of circulation
(a)Irregular heartbeat
(b)Hypotension
(c)Weakness and exhaustion
(d)Circulatory system collapse
(e)Lowered blood pressure
(2) Severe headache, dizziness, blurred vision, hearing difficulty, confusion and unconsciousness
(3)Nausea, vomiting and diarrhea
(4)Chills and rapid onset of fever
(5)Muscular incoordination and twitching
(6)Excessive perspiration
(7)Respiratory difficulty leading to respiratory arrest
d. Hydrophidae Bite:
(1)Stiffness, muscle aches and spasms of the jaw.
(2)Moderate to severe pain to the effected limb.
(3)Blurred vision and drowsiness.
(4)Respiratory paralysis.
e. Persistent myths about sea snakes include the mistaken idea that they cannot bite effectively. The truth is that though their teeth are small; about 2.5 mm, they are adequate to penetrate skin and they can open their mouths wide enough to bite a person’s thigh. Envenomation from sea snakes is rare, due in most part to their temperament, but does occur. Without treatment, death from sea snake envenomation can occur within 12-24 hours.
5.TREATMENT OF A SNAKE BITE
a.Most definitive care for snake envenomation is anti-venom.
b.Keep the victim calm and reassured. If possible, allow the limb to rest at a neutral level in relation to the victim’s heart.
c.Locate the bite site
d.If the bite is on the hands or feet, immediately remove any rings, bracelets, watches or any constricting items from the extremity.
e.Wrap leg or arm rapidly with 3” to 6” ACE bandage past the knee or elbow joint to immobilize it. Leave the fang marks open.
f.Apply a splint
g.Check distal pulses
h.Monitor and evacuate ASAP
i. COMMON DON’TS
(1)DO NOT cut or incise the bite site
(2)DO NOT apply ice or heat to the bite site.
(3)DO NOT apply oral (mouth) suction.
(4)DO NOT remove dressings/elastic wraps.
(5)DO NOT try to kill the snake for identification as this may lead to other people being bitten.
(6)DO NOT have the victim eat or drink anything.
6. PREVENTION OF SNAKE BITES
a. LEAVE THE SNAKE ALONE!! - This is the best way to avoid snakebite. Most snakes will only bite if threatened. Most snake bites occur when the victim is attempting to catch, kill or play with a snake. Keep hands out of areas that you cannot see (i.e. holes, under rocks and under logs).
7. ARTHROPOD ENVENOMATION
a. Bees, Wasps and Ant Stings- Most of this group sting their victims. Their primary effect is from the strong histamine reaction they cause.
(1) Signs and Symptoms:
(a)Bee/Wasp stings – Honey bees only sting once and leave the stingers and venom sac embedded in the skin. Wasps, hornets, and bumble bees can sting multiple times.
1.Pain
2.Itching/burning sensation
3.Wheal – Raised, inflame skin
4.If patient is allergic, monitor for anaphylactic reaction
(b) Ant sting - Some species of ants, especially the fire ant, can bite and sting repeatedly.
1.Pain
2.Itching/burning sensation
3.Vesicles
4.If patient is allergic, monitor for anaphylactic reaction
5.Multiple bites – can produce the following symptoms:
a.Vomitting
b.Diarrhea
c.Generalized edema
d.Hypotension – due to vasodilation
e.Dysuria
(2) Treatment:
(a) Stingers should be removed immediately to prevent more venom from entering the victim.
1.Remove the stinger by scraping across the skin with a knife blade, ID card or similar object. Grasping the stinger with tweezers only injects the remaining venom into the victim.
(b)Apply ice to the affected area
(c)Apply Hydrocortisone Cream 1% to affected area BID (twice a day)
(d)For anaphylaxis:
1.Benadryl injectable 50mg SQ
2.Epinephrine 0.3-0.5mg 1:1000 SQ
(3) Prevention:
(a)Leave them alone
(b)Avoid nesting sites
(c)Personnel with known allergies should carry an Epi-Pen or Ana-kit
b. Centipedes, Millipedes, and Caterpillars
(1) Signs and symptoms:
(a) Millipedes - Millipedes secrete a toxin on their skin
(1)Itching
(2)Burning
(b) Centipedes - Caused by a bite:
(1)Immediate severe pain
(2)Redness
(3)Swelling
(4)Necrosis and ulceration may sometimes occur
(c) Caterpillars - Some caterpillars have venom in hollow hairs all over their bodies.
(1)Severe burning
(2)Pain
(3)Redness
(4)Swelling
(5)Necrosis
(2) Treatment:
(a)Similar to that of a bee sting. Focus mainly on anaphylactic reaction.
(b)For millipedes, wash skin with soap and water to remove secretions.
(c)For caterpillars, use scotch tape to remove hairs from skin. Do not rub area.
(3) Prevention:
(a)Leave them alone
(b)Avoid known nesting sites and hives
(c)Shake out sleeping bags and clothing and check boots before putting them on.
c. Spider Envenomation:
(1)Black Widow Spider - Only the female bites and has a neurotoxic venom
(a)Description – Glossy black with a red hourglass on the underside of the abdomen. Other species of widow spiders include Brown and Red Widows. All are poisonous and all have a red hourglass pattern on abdomen.
(b) Signs and Symptoms:
1.Initial pain is not severe, but severe local pain rapidly develops
2.The pain gradually spreads over the entire body and settles in the abdomen and legs
3.Weakness
4.Sweating
5.Excessive salivation
6.Rash may occur
7.Tremors
8.Nausea
9.Vomiting
10. Respiratory muscle weakness combined with pain may lead to respiratory arrest
11. Anaphylactic reactions can occur, but are rare
12. Symptoms usually regress after several hours and are usually gone in a few days
(c) Treatment:
1.Clean site with soap and water
2.Intermittent ice for 30 minutes each hour
3.Supportive care
4.Antibiotics if infection occurs
(2) Brown Recluse Spider - Venom is cytotoxic. (Necrotic in nature)
(a) Description- They are small, light brown, and have a dark brown violindesign on the top of their thorax.
(b) Signs and symptoms
1.Painless bite. Most often, the victim does not know they have been bitten.
2.A painful red area with a cyanotic center appears after a few hours.
3.A macular rash (a discolored area of skin that is not raised above the surface) may occur.
4.After 2 or 3 days, there is an area of discoloration that does not blanch with pressure.
5.After a week or two, the area turns dark and the scab falls off leaving an ulcer.
6.After this happens, secondary infection and regional lymphadenopathy occur.
7.The ulcer will persist for weeks or months.
8.In many cases a systemic reaction may occur that is serious and may lead to death.
9.The systemic reactions occur mainly in children and include fever, chills, joint pain, splenomegaly, vomiting, and a generalized rash. These reactions may occur at any time that the ulcer is present.
(c) Treatment:
1.Cold compresses intermittently for the first four (4) days
2.Apply bacitracin
3.It is necessary to excise all the indurated (hardened) skin and fascia before healing will begin.
4.If the ulcer is not excised, it will continue to grow until it is several inches in diameter.
5.Provide supportive care as necessary.
6.Tetanus prophylaxis and antibiotics are necessary to control secondary infection.
7.Anaphylactic reactions may occur.
d. Scorpion Envenomation:
(1) Description - These arthropods inhabit temperate climates around the world and number greater than 650 species. Fifty species can cause serious injury.
(a) The most dangerous scorpions in the U.S. inhabit Arizona and portions of California, Texas, and New Mexico. Although the size and shape of these arthropods can be both intimidating and frightening, envenomation, although potentially painful, very rarely produces mortality in humans.
(2) Signs and Symptoms:
(a)Erythema
(b)Edema
(c)Local pain and or paresthesia (an abnormal touch sensation such as burning or prickling often in the absence of external stimulas) at site of sting.
(d)Pain or paresthesia remote from the site of sting in addition to local
findings.
(e)Cranial nerve dysfunction - Blurred vision, wandering eye movements,
hypersalivation, trouble swallowing, tongue twitching/spasms,
problems with upper airway, slurred speech.
(f)Somatic skeletal neuromuscular dysfunction - Jerking of extremity(ies), restlesness, severe involuntary shaking and jerking that may be mistaken for a siezure.
(3) Diagnosis:
(a) Positive “Tap Test”: excruciating pain when tapping on the affected area. This is the only true way to diagnose a scorpion sting.
(4) Treatment:
(a)Based on the level of envenomation
(b)ABC’s
(c)Ice applied to the site for 30 minutes each hour until symptoms subside
(d)Oral analgesics
(5) Prevention:
(a)Wear shoes
(b)When in the field, bedclothes, sleeping bags, and shoes should be shaken out prior to use
(c)Many scorpions inhabit brush and debris piles in search of its prey. If one is coming in contact with this type of material, it is wise to wear gloves.
(d)Remove wood and rubbish piles around camp
(e)Cracks and recesses in rural desert dwellings should be filled
REFERENCES
Tropical Medicine (7th ed.), Pgs 877-888
Wilderness Medicine (3rd ed.), Ch 28, pgs 680-884, 704-705; Ch 31, pgs 743-768
Hospital Corpsman NAVEDTRA 14295, Pgs 5-12
Poisonous Snakes of the World, NAVMED P-5099 Pgs 83, 107, and 117