Identification
of a fish following a sting is not always possible; however, symptoms and effects
of venom do not vary greatly. Venomous fish are rarely aggressive and usually
contact is made by accidentally stepping on or handling the fish. Dead fish spines
remain toxic (see Figure 5C-5). Venom is generally heat-labile and may be
decomposed by hot water. Local symptoms following a sting may first include
severe pain later combined with numbness or even hypersensitivity around the
wound. The wound site may become cyanotic with surrounding tissue becoming
pale and swollen. General symptoms may include nausea, vomiting, sweating,
mild fever, respiratory distress and collapse. The pain induced may seem disproportionately
high to apparent severity of the injury. Medical personnel should be
prepared for serious anaphylactic reactions from apparently minor stings or
envenomation.
Figure 5c-5. Venomous Fish. Shown is the weeverfish.
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Avoid handling suspected venomous fish. Venomous fish are often
found in holes or crevices or lying well camouflaged on rocky bottoms. Divers
should be alert for their presence and should take care to avoid them.
1. Get victim out of water; watch for fainting.
2. Lay patient down and reassure.
3. Observe for signs of shock.
4. Wash wound with cold, salt water or sterile saline solution. Surgery may be
required to open up the puncture wound. Suction is not effective to remove
this toxin.
5. Soak wound in hot water for 30 to 90 minutes. Heat may break down the
venom. The water should be as hot as the victim can tolerate but not hotter
than 122ºF (50ºC). Immersion in water above 122ºF (50ºC) for longer than a
brief period may lead to scalding. Immersion in water up to 122ºF (50ºC)
should therefore be brief and repeated as necessary. Use hot compresses if the
wound is on the face. Adding magnesium sulfate (epsom salts) to the water
offers no benefit.
6. Calcium gluconate injections, diazepam, or methocarbamol may help to
reduce muscle spasms. Infiltration of the wound with 0.5 percent to 2.0 percent
xylocaine with no epinephrine is helpful in reducing pain. If xylocaine
with epinephrine is mistakenly used, local necrosis may result from both the
toxin and epinephrine present in the wound. Narcotics may also be needed to
manage severe pain.
7. Clean and debride wound. Spines and sheath frequently remain. Be sure to
remove all of the sheath as it may continue to release venom.
8. Tourniquets or ligatures are no longer advised. Use an antiseptic or antibiotic
ointment and sterile dressing. Restrict movement of the extremity with immobilizing
splints and cravats.
9. Administer tetanus prophylaxis as appropriate.
10. Treat prophylactically with topical antibiotic ointment. If delay in treatment
has occurred, it is recommended that the wound be cultured prior to administering
systemic antibiotics.
The sea snake is an air-breathing reptile which has adapted to its
aquatic environment by developing a paddle tail. Sea snakes inhabit the Indo-
Pacific area and the Red Sea and have been seen 150 miles from land. The most
dangerous areas in which to swim are river mouths, where sea snakes are more
numerous and the water more turbid. The sea snake is a true snake, usually 3 to 4
feet in length, but it may reach 9 feet. It is generally banded (Figure 5C-11). The
sea snake is curious and is often attracted by divers and usually is not aggressive
except during its mating season.
Figure 5c.11. Sea
Snake.
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The sea snake injects a poison that has 2 to 10 times the
toxicity of cobra venom. The bites usually appear as four puncture marks but may
range from one to 20 punctures. Teeth may remain in the wound. The neurotoxin
poison is a heat-stable nonenzymatic protein; hence, sea snake bites should not be
immersed in hot water as with venomous fish stings. Due to its small jaws, bites
often do not result in envenomation. Sea snake bites characteristically produce
little pain and there is usually a latent period of 10 minutes to as long as several
hours before the development of generalized symptoms: muscle aching and stiffness,
thick tongue sensation, progressive paralysis, nausea, vomiting, difficulty with speech and swallowing, respiratory distress and failure, plus smoky-colored
urine from myoglobinuria, which may go on to kidney failure.
Wet suits or protective clothing, especially gloves, may provide
substantial protection against bites and should be worn when diving in waters
where sea snakes are abundant. Also, shoes should be worn when walking where
sea snakes are known to exist, including in the vicinity of fishing operations. Do
not handle sea snakes. Bites often occur on the hands of fishermen attempting to
remove snakes from nets.
1. Keep victim still.
2. Do not apply a loose constricting band or tourniquet. Apply direct pressure
using a compression bandage and immobilize the extremity in the dependent
position with splints and elastic bandages. This prevents spreading of the neurotoxin
through the lymphatic circulation.
3. Incise and apply suction (see cone shell stings, paragraph 5C-3.9).
4. Transport all sea snake-bite victims to a medical facility as soon as possible,
regardless of their current symptoms.
5. Watch to ensure that the patient is breathing adequately. Be prepared to
administer mouth-to-mouth resuscitation or cardiopulmonary resuscitation if
required.
6. The venom is a heat-stable protein which blocks neuromuscular transmission.
Myonecrosis with resultant myoglobinuria and renal damage are often seen.
Hypotension may develop.
7. Respiratory arrest may result from generalized muscular paralysis; intubation
and mechanical ventilation may be required.
8. Renal function should be closely monitored and peritoneal or hemodialysis
may be needed. Alkalinization of urine with sufficient IV fluids will promote
myoglobin excretion. Monitor renal function and fluid balance anticipating
acute renal failure.
9. Vital signs should be monitored closely. Cardiovascular support plus oxygen
and IV fluids may be required.
10. Because of the possibility of delayed symptoms, all sea snake-bite victims
should be observed for at least 12 hours.
11. If symptoms of envenomation occur within one hour, antivenin should be
administered as soon as possible. In a seriously envenomated patient, antivenin
therapy may be helpful even after a significant delay. Antivenin is available from the Commonwealth Serum Lab in Melbourne, Australia (see
Reference D of this appendix for address and phone number). If specific antivenin
is not available, polyvalent land snake antivenin (with a tiger snake or
krait Elapidae component) may be substituted. If antivenin is used, the directions
regarding dosage and sensitivity testing on the accompanying package
insert should be followed and the physician must be ready to treat for anaphylaxis
(severe allergic reaction). Infusion by the IV method or closely
monitored drip over a period of one hour, is recommended.
12. Administer tetanus prophylaxis as appropriate.
Sponges are composed of minute multicellular animals with spicules of
silica or calcium carbonate embedded in a fibrous skeleton. Exposure of skin to
the chemical irritants on the surface of certain sponges or exposure to the minute
sharp spicules can cause a painful skin condition called dermatitis.
Avoid contact with sponges and wear gloves when handling live
sponges.
1. Adhesive or duct tape can effectively remove the sponge spicules.
2. Vinegar or 3- to 10-percent acetic acid should be applied with saturated compresses
as sponges may be secondarily inhabited by stinging coelenterates.
3. Antihistamine lotion (diphenhydra-mine) and later a topical steroid (hydrocortisone),
may be applied to reduce the early inflammatory reaction.
4. Antibiotic ointment is effective in reducing the chance of a secondary
infection.
Stings by stonefish, zebrafish,
and scorpionfish have been known to cause fatalities. While many
similarities exist between these fish and the venomous fish of the previous section,
a separate section has been included because of the greater toxicity of their venom
and the availability of an antivenin. The antivenin is specific for the stonefish but
may have some beneficial effects against the scorpionfish and zebrafish. Local
symptoms are similar to other fish envenomation except that pain is more severe
and may persist for many days. Generalized symptoms are often present and may
include respiratory failure and cardiovascular collapse. These fish are widely distributed
in temperate and tropical seas and in some arctic waters. They are
shallow-water bottom dwellers. Stonefish and scorpionfish are flattened vertically,
dark and mottled. Zebrafish are ornate and feathery in appearance with alternating
patches of dark and light color (see Figure 5C-6)
Figure 5c-6. Highly Toxic Fish.
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Prevention is the same as for venomous fish (paragraph 5C-3.1.1).
1. Give the same first aid as that given for venomous fish (paragraph 5C-3.1.2).
2. Observe the patient carefully for the possible development of life-threatening
complications. The venom is an unstable protein which acts as a myotoxin on
skeletal, involuntary, and cardiac muscle. This may result in muscular paralysis,
respiratory depression, peripheral vasodilation, shock, cardiac
dysrhythmias, or cardiac arrest.
3. Clean and debride wound.
4. Antivenin is available from Commonwealth Serum Lab, Melbourne, Australia
(see Reference 4 at end of this appendix for address and phone number). If
antivenin is used, the directions regarding dosage and sensitivity testing on the
accompanying package insert should be followed and the physician must be
ready to treat for anaphylactic shock (severe allergic reaction). In brief, one or
two punctures require 2,000 units (one ampule); three to four punctures, 4,000
units (two ampules); and five to six punctures, 6,000 units (three ampules).
Antivenin must be delivered by slow IV injection and the victim closely monitored
for anaphylactic shock.
5. Institute tetanus prophylaxis, analgesic therapy and antibiotics as described for
other fish stings. 5C-3.1.1).
The stingray is common
in all tropical, subtropical, warm, and
temperate regions. It usually favors
sheltered water and will burrow into
sand with only eyes and tail exposed.
It has a bat-like shape and a long tail
(Figure 5C-7). Approximately 1,800
stingray attacks are reported annually
in the U.S. Most attacks occur when
waders inadvertently step on a ray,
causing it to lash out defensively with
its tail. The spine is located near the
base of the tail. Wounds are either of
the laceration or puncture type and
are extremely painful. The wound
appears swollen and pale with a blue rim. Secondary wound infections are
common. Systemic symptoms may be present and can include fainting, nausea,
vomiting, sweating, respiratory difficulty, and cardiovascular collapse.
Figure 5c-7. Stingray.
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In shallow waters which favor stingray habitation, shuffle feet on the
bottom and probe with a stick to alert the rays and chase them away.
1. Control local bleeding.
2. Clean and debride the wound and cover with a clean dressing.
3. For suspected blue-ringed octopus bites, do not apply a loose constrictive
band. Apply direct pressure with a pressure bandage and immobilize the
extremity in a position that is lower than the heart using splints and elastic
bandages.
4. Be prepared to administer mouth-to-mouth resuscitation and cardiopulmonary
resuscitation if necessary.
5. Blue-ringed octopus venom is heat stable and acts as a neurotoxin and neuromuscular
blocking agent. Venom is not affected by hot water therapy. No
antivenin is available.
6. Medical therapy for blue-ringed octopus bites is directed toward management
of paralytic, cardiovascular, and respiratory complications. Respiratory arrest
is common and intubation with mechanical ventilation may be required. Duration
of paralysis is between 4 and 12 hours. Reassure the patient.
7. Administer tetanus prophylaxis as appropriate.
This invertebrate
type varies according to region and is found in warm, tropical or
temperate zones. It is usually found under rocks or coral and is especially common
in the tropical Pacific, Bahamas, Florida Keys, and Gulf of Mexico. Annelida have
long, segmented bodies with stinging bristle-like structures on each segment.
Some species have jaws and will also inflict a very painful bite. Venom causes
swelling and pain.
Wear lightweight, cotton gloves to protect against bloodworms, but
wear rubber or heavy leather gloves for protection against bristleworms.
1. Remove bristles with a very sticky tape such as adhesive tape or duct tape.
Topical application of vinegar will lessen pain.
2. Treatment is directed toward relief of symptoms and may include topical steroid
therapy, systemic antihistamines, and analgesics.
3. Wound infection can occur but can be easily prevented by cleaning the skin
using an antiseptic solution of 10 percent povidone-iodine and topical antibiotic
ointment. Systemic antibiotics may be needed for established secondary
infections that first need culturing, aerobically and anaerobically.
There are various species of sea urchins with widespread distribution.
Each species has a radial shape and long spines. Penetration of the sea urchin
spine can cause intense local pain due to a venom in the spine or from another type
of stinging organ called the globiferous pedicellariae. Numbness, generalized
weakness, paresthesias, nausea, vomiting, and cardiac dysrhythmias have been
reported.
Avoid contact with sea urchins. Even the short-spined sea urchin can
inflict its venom via the pedicellariae stinging organs. Protective footwear and
gloves are recommended. Spines can penetrate wet suits, booties, and tennis
shoes.
1. Remove large spine fragments gently, being very careful not to break them
into small fragments that remain in the wound.
2. Bathe the wound in vinegar or isopropyl alcohol. Soaking the injured extremity
in hot water up to 122ºF (50ºC) may help. Caution should be used to
prevent scalding the skin which can easily occur after a brief period in water
above 122ºF (50ºC).
3. Clean and debride the wound. Topical antibiotic ointment should be used to
prevent infection. Culture both aerobically and anaerobically before administering
systemic antibiotics for established secondary infections.
4. Remove as much of the spine as possible. Some small fragments may be
absorbed by the body. Surgical removal, preferably with a dissecting microscope,
may be required when spines are near nerves and joints. X-rays may be
required to locate these spines. Spines can form granulomas months later and
may even migrate to other sites.
5. Allergic reaction and bronchospasm can be controlled with subcutaneous epinephrine
(0.3 cc of 1:1,000 dilution) and by using systemic antihistamines.
There are no specific antivenins available.
6. Administer tetanus prophylaxis as appropriate.
7. Get medical attention for deep wounds..
The cone shell is widely distributed
in all regions and is usually found under
rocks and coral or crawling along sand. The
shell is most often symmetrical in a spiral coil,
colorful, with a distinct head, one to two pairs
of tentacles, two eyes, and a large flattened foot
on the body (Figure 5C-10). A cone shell sting
should be considered as severe as a poisonous
snake bite. It has a highly developed venom
apparatus: venom is contained in darts inside
the proboscis which extrudes from the narrow
end but is able to reach most of the shell. Cone
shell stings are followed by a stinging or
burning sensation at the site of the wound.
Numbness and tingling begin at the site of the
wound and may spread to the rest of the body;
involvement of the mouth and lips is severe.
Other symptoms may include muscular paralysis,
difficulty with swallowing and speech,
visual disturbances, and respiratory distress.
Figure 5c.10. Cone Shell.
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Avoid handling cone shells. Venom can be injected through clothing
and gloves
1. Lay the patient down.
2. Do not apply a loose constricting band or ligature. Direct pressure with a pressure
bandage and immobilization in a position lower than the level of the heart
using splints and elastic bandages is recommended.
3. Some authorities recommend incision of the wound and removal of the venom
by suction, although this is controversial. However, general agreement is that
if an incision is to be made, the cuts should be small (one centimeter), linear
and penetrate no deeper than the subcutaneous tissue. The incision and suction
should only be performed if it is possible to do so within two minutes of the
sting. Otherwise, the procedure may be ineffective. Incision and suction by
inexperienced personnel has resulted in inadvertent disruption of nerves, tendons,
and blood vessels.
4. Transport the patient to a medical facility while ensuring that the patient is
breathing adequately. Be prepared to administer mouth-to-mouth resuscitation
if necessary.
5. Cone shell venom results in paralysis or paresis of skeletal muscle, with or
without myalgia. Symptoms develop within minutes of the sting and effects
can last up to 24 hours.
6. No antivenin is available.
7. Respiratory distress may occur due to neuromuscular block. Patient should be
admitted to a medical facility and monitored closely for respiratory or cardiovascular
complications. Treat as symptoms develop.
8. Local anesthetic with no epinephrine may be injected into the site of the
wound if pain is severe. Analgesics which produce respiratory depression
should be used with caution.
9. Management of severe stings is supportive. Respiration may need to be supported
with intubation and mechanical ventilation.
10. Administer tetanus prophylaxis as appropriate.
