IMMEDIATE FIRST AID
for bites by
Indian or Common Cobra
(Naja naja naja)
In the event of an actual or probable bite from an Indian or Common Cobra,
execute the following first aid measures without delay.
Snake:
- Make sure that the responsible snake or snakes have been
appropriately and safely contained, and are out of danger of inflicting any
additional bites.
Transportation:
- Immediately call for transportation.
Telephone:
Victim:
- Keep the victim calm and reassured. Allow him or her to lie flat and
avoid as much movement as possible. If possible, allow the bitten limb to
rest at a level lower than the victim's heart.
- Immediately wrap a large crepe bandage snugly around the bitten limb
starting at the site of the bite and working proximally up the limb (the full
length if possible). The bandage should be as tight as one might bind a
sprained ankle. (See the attached copy from "First Aid for Snakebite", by
Dr. S.K. Sutherland.)
- Secure the splint to the bandaged limb to keep the limb as rigid and
unmoving as possible. Avoid bending or moving the limb excessively while
applying the splint.
- DO NOT remove the splint or bandages until the victim has reached the
hospital and is receiving Antivenom.
- Have the Haffkine Bio-Pharmaceutical Corp. Polyvalent Antivenom ready
for the emergency crew to take with the victim to the hospital. Give them the
following:
- the available antivenom (at least 10 vials)
- the accompanying instruction (Protocol) packet
- the victim's medical packet (if available)
DO NOT cut or incise the bite site
DO NOT apply ice to the bite site
Summary for Human Bite
by
Indian or Common Cobra
(Naja naja naja)
The bite of the Common Cobra with envenomation can be rapidly fatal
(possibly as early as 60 minutes). Please read the attached Medical Management
Protocol and respond appropriately.
- First Aid:
- Bandage and Immobilize the bitten limb with crepe bandages and splint
as described in the Immediate First Aid section. Rest this extremity below the
level of the patient's heart (if practical).
- Transport to a medical center emergency or trauma service.
- Medical Management:
- Call your local Poison Control Center or the San Diego Regional Poison
Control Center (800 876-4766). They should locate a consultant to help you
treat this patient.
- Observe for Signs and Symptoms of Envenomation.
- If signs or symptoms are present, perform the following:
- Administer Lactated Ringers Solution at 200 to 250 mls per hour.
- Draw samples and collect initial laboratory data.
- Reconstitute the contents of 2 vials (20 mls) of Haffkine
Bio-Pharmaceutical Corp. Polyvalent Antivenom with Lactated Ringers Solution
(10 mls/vial). Administer the antivenom I.V. piggyback over 20 minutes at a
rate of 1 vial (10 mls) per 10 minutes.
- Remove the splints and crepe bandage slowly over a period of 10
minutes. If symptoms progress rapidly, reapply the bandage, and administer an
additional vial of antivenom. Again attempt to remove the bandage.
- Allergic or untoward reactions to the antivenom should be treated with
Corticosteroids, Epinephrine, Benadryl, Atarax and/or Antihistamines as
appropriate.
- Monitor Signs, Symptoms, and Laboratory data, and administer additional
antivenom in 1 vial (10 mls) increments at a rate of 1 vial per 10 minutes as
necessary to control the progression of symptoms.
- The required amount of antivenom will vary with the severity of
envenomation. One should anticipate using (including the initial dose):
3-5 vials total for a minor bite with envenomation.
10-15 vials or more may be necessary for moderate or severe bites.
MEDICAL MANAGEMENT
for bites by
Indian or Common Cobra
(Naja naja naja)
This person has received a bite and probable envenomation from an Indian or
Common Cobra (Naja naja naja). This is a very venomous and dangerous snake.
In this particular species, envenomation usually presents predominately with
local necrosis and systemic manifestations. Drowsiness, Neurological and
Neuromuscular symptoms may develop early; paralysis, ventilatory failure or
death could ensue rapidly.
Please read and execute the following procedures without delay.
- A crepe bandage and splint have been applied as immediate first aid
adjuncts to retard the absorption of the venom. DO NOT remove until the
patient has arrived at the hospital and is receiving the antivenom.
- Make sure that at least 10 packages of Haffkine Institute Polyvalent
Antivenom are present with the patient. This antivenom contains the
appropriate fractions necessary to neutralize the components of Indian Cobra
venom.
- If the patient has been envenomated, the treatment is 3 to 10 vials of
intravenous antivenom. Envenomation is diagnosed by the presence of
characteristic signs and symptoms. Necessary information follows and is
organized in sections:
- Signs and Symptoms of Envenomation
- Medical Management
- General Considerations
- Special Considerations
- Consultants
- References
Signs and Symptoms of Envenomation:
- Neurological and Neuromuscular: These signs and symptoms will usually
manifest earliest. Not all of these will necessarily develop, even with severe
envenomation.
Drowsiness
| (>90%)
|
Eyelid drooping (Ptosis) | (75-85%)
|
Respiratory paralysis or Dyspnea | (70-80%)
|
Ophthalmoplegia | (35-45%)
|
Palatal paralysis | (30-40%)
|
Glossopharyngeal paralysis | (30-40%)
|
Limb paralysis | (20-30%)
|
Convulsions | (10-20%)
|
Head drooping (Cervical muscle paresis or paralysis)
|
Headache
|
Sudden loss of consciousness
|
Stumbling gait (Ataxia)
|
- General: These symptoms typically manifest within one to four hours
following the bite if envenomation occurred.
- Nausea and Vomiting
- Hypotension
- Flushing of the face
- Warm skin
- Pain around bite site
- Abdominal Pain
- Cardiotoxicity: Increased Blood Pressure and increased Cardiac Output
followed by Myocardial Depression and Asystole. Mortality approaches 100% if
cardiotoxic complications occur.
- Local Symptoms: In some Cobra bites, local tissue destruction and
necrosis can dominate the clinical presentation. Gangrene requiring amputation
can occur. Local tissue damage appears to be less frequent and less severe in
most cases of Indian Cobra (Naja naja naja) envenomation, but may
include:
- Localized discoloration of skin
- Vesiculation (usually small and localized)
- Necrosis (can be extensive, but is characteristically localized to
the bite site)
- Local edema (usually minimal)
- Fang Marks: Fang marks may be present as one or more well defined
punctures, 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 preclude the possibility of a bite (especially if a juvenile snake is involved). In
general, the fang marks from an Indian Cobra tend to be small, but deep. The
snake in delivering the bite may hold on and chew savagely, and may inject up
to 60% of its venom. Multiple bites inflicted by a single snake or by more than
one snake are also possible, and should be noted if present (See Special
Considerations below). The presence of fang marks does not always imply that
the injection or deposition of venom into the bite wound (envenomation)
actually occurred.
Medical Management:
- Admit patient to an emergency or trauma service and call the consultant
identified by the Poison Control Center.
- Begin a peripheral intravenous infusion (16 gauge catheter) of Lactated
Ringers Solution at a rate of 250 cc/hour.
- Draw blood from the unbitten extremity, and collect urine for the
following laboratory tests. Mark STAT.
- Type and Cross Match TWO units of Whole blood.
- CBC with differential.
- Coagulation Parameters:
- Prothrombin Time (PT)
- Partial Thromboplastin Time (PTT)
- Platelet Count
- Fibrinogen levels
- Fibrin Degradation Products
- Serum Electrolytes, BUN/Creatinine, Calcium, Phosphorus.
- Lactate Dehydrogenase (with Isoenzyme analysis). Isoenzyme analysis may
indicate multiple targets of the venom components which may dictate further
management.
- Urinalysis (Macroscopic and Microscopic Analysis). Must include analysis
for:
- Free Protein
- Hemoglobin
- Electrocardiogram (Place the patient on continuous monitoring).
- Additional Tests as needed or indicated by patient's hospital
course.
- It may be necessary or practical to repeat some or all of the above
serum and urine tests periodically over the hospital course to monitor the
effects of antivenom therapy or to detect late changes in parametric
values.
- OBSERVE PATIENT CLOSELY for signs and symptoms of envenomation which
usually manifest between 15 minutes and two hours following the bite.
- If NO signs or symptoms have been noted after TWO hours, there is the
possibility that the patient received a dry bite (no venom injected).
- VERY SLOWLY begin to remove the bandages and splint watching carefully
for any changes in the patient's status. If any changes occur, assume the
patient has been envenomed and prepare to give antivenom immediately (as
directed below).
- If signs and symptoms still fail to manifest, continue CLOSE observation
of the patient for an additional 24 hours.
- IF ANY SIGN OR SYMPTOM becomes apparent or has been noted during the
course of evaluation, begin Antivenom Therapy as follows:
- Each vial of Haffkine Institute Polyvalent Antivenom is packaged as a
lyophilized dry preparation in a glass vial with an accompanying vial of
sterile water (to reconstitute the antivenom). It is preferable to
reconstitute the antivenom in Lactated Ringers Solution. The contents of TWO
vials of antivenom are to be used as the Initial dose. CAREFULLY score both
vials, and break open. Withdraw 20 ml of room temperature Lactated Ringers
Solution into a sterile syringe, and then transfer 10 ml to each antivenom
vial.
- Carefully mix and reconstitute the antivenom in each vial by covering
the open ends with several thicknesses of sterile gauze sponges and then
shaking each vial vigorously for one minute. Allow the vials to stand still
for one minute to clear. Withdraw the CLEAR solution into a clean sterile
syringe (leaving froth and undissolved particles behind), and prepare to
transfer to intravenous piggyback set-up.
- Administer the reconstituted Antivenom intravenously over a period of 20
minutes at a rate of 1 vial per 10 minutes (i.e., 1.0 mls per minute).
- Should any signs of ALLERGY/ANAPHYLAXIS (e.g., coughing, dyspnea,
urticaria, itching, increased oral secretions, etc.) develop, immediately
discontinue the
administration of antivenom, and treat symptoms with epinephrine, steroids
and antihistamines. As soon as the patient is stabilized, continue the
antivenom infusion at a slower rate.
- After the first two vials of antivenom has been administered, the splint
and the bandages may be removed. This should be done VERY SLOWLY over a FIVE
minute period to prevent a bolus release of venom. If the patient's condition
worsens:
- Reapply the crepe bandage.
- Prepare a third vial of antivenom (1 vial in 10 mls of Lactated Ringers
Solution) immediately as directed above.
- Infuse this dose at 1.0 ml per minute for 10 minutes.
- Release the bandage again slowly over 5 minutes.
- In any case, an additional vial of antivenom should be prepared and
allowed to dissolve fully. Anticipate giving this next dose approximately Two
hours after the first two vials has been delivered. If the patient's symptoms
should persist or worsen, administer this dose 60 or 90 minutes following the
first dose or doses.
- Antivenom Therapy is the mainstay of treatment for cobra envenomation.
Many of the symptoms are ameliorated or entirely eliminated by the antivenom
alone. Other symptoms will require additional modalities of therapy to
correct. Local symptoms may take several days to weeks to completely resolve;
their progression, however, may be treated with antivenom therapy.
- Neurological Symptoms (especially respiratory obstruction or failure)
are usually the most immediate cause of dangerous problems. Often, these are
improved by the antivenom. If breathing becomes impaired, provide respiratory
assistance. Secretions may become copious, necessitating suctioning.
- Hematological symptoms may present as a Disseminated Intravascular
Coagulopathy, and are treated as are other DICs. This, however, is uncommon
with cobra envenomation.
- Renal symptoms are rare in cobra envenomation, but may complicate the
situation, and if severe (i.e., Acute Renal Failure) may necessitate Peritoneal
Dialysis.
- If severe muscle paralysis develops and persists, administer 0.6 mg of
Atropine IV. Follow by giving 0.5 mg of Neostigmine IV every 30 minutes for a
maximum of FIVE doses.
- It is important to keep venom neutralization current and continuous.
The best method to accomplish this is to keep a close watch on the patient's
status. If the present condition does not improve, or should it worsen for any
reason, additional antivenom should be administered. The antivenom should
ideally be diluted 1 to 10 in Lactated Ringers Solution, and always given by
intravenous infusion at a rate of One vial per 10 minutes (1.0 mls per min).
Give all additional antivenom in one vial doses. One should anticipate using
Three to Five vials for a minor bite. Ten to Fifteen may be necessary for
moderate or severe bites.
- It is advisable to perform periodic serum and urine analyses during
therapy (as outlined above).
- It is always best to keep the patient in an Intensive Care setting
until free of major symptoms for 24 hours. The patient should be observed in
the hospital for at least 24 hours after symptoms are stabilized.
General Considerations:
- It is important that the patient be placed at rest, kept warm, and
avoids unnecessary movement.
- The onset of dangerous Neurotoxic symptoms can be rapid and
subtle. In addition, they are more rapidly reversed in their early stages than
when fully developed. It may be necessary to wake the patient and perform a
brief neurologic check every hour or so to assure that breathing and other
neurological functions are not impaired. Carefully note the progress of any
paralysis which maybe present.
- Respiratory obstruction and failure are the greatest immediate
concerns. Should the patient develop difficulties in breathing or airway
management, respiratory support will be required. If the tongue, jaw or
pharynx become paralyzed, insert an oral airway; intubation may be required.
Make sure adequate suction equipment is available and operative.
- Fluid management is very important in snake bite cases. The
patient should be well hydrated and a brisk urine output maintained.
- If any signs of Oropharyngeal paralysis or impaired
swallowing exist, give NOTHING BY MOUTH, and keep patient on his side
with head down. Watch for airway compromise and aspiration.
- Morphine is CONTRAINDICATED because of its tendency to suppress
respiration. Alcohol should also be avoided.
- In cases in which Circulatory Shock remains uncorrected by
antivenom therapy, plasma volume expanders and/or vasopressor agents may be
given with appropriate considerations.
- Tetanus prophylaxis should be current.
- Antibiotics are NOT recommended prophylactically.
Special Considerations:
- Local Necrosis:
- The degree of local necrosis appears to be less with Indian
Cobra (Naja naja naja) envenomation than with other Naja naja subspecies.
Prompt delivery of antivenom following the bite may lessen the extent of local
tissue damage, although some evidence suggests that certain antivenoms have
less efficacy in ameliorating or protecting against the local action of certain
cobra venoms. This latter statement should not be held as a contraindication
to the use of antivenom in those cases of cobra bite in which local symptoms
predominate.
- Multiple Bites:
- It is possible for a cobra to deliver more than one bite in a single
attack, and thus may inject a larger volume of venom. If there is evidence
that such an attack occurred (i.e., history or multiple bite sites), twice
(2X) the initial dose of antivenom should be given: (i.e., four vials in 40
mls of Lactated Ringers solution delivered over 40 minutes at a rate of one
vial per ten minutes). Always watch closely for signs of allergic response; if
they occur, treat appropriately and slow infusion rate. Give all subsequent
doses in One vial increments at 1 vial per 10 minutes as necessitated by the
presence of continued signs and symptoms.
- Severe Envenomation:
- If the patient shows severe signs of envenomation, particularly if early
after the bite, treat as a multiple bite administering four vials of antivenom
over the first 40 minutes. Give all subsequent doses in ONE vial increments at
a rate of one vial per 10 minutes as necessitated by the presence of continued
signs and symptoms.
- Testing for Equine Protein Sensitivity:
- It is NOT ADVISABLE to utilize subcutaneous or intradermal testing for
sensitivity to equine products in that such testing may be unreliable, and may
unnecessarily delay antivenom therapy which must be used if any signs of cobra
envenomation are present.
- If there is reason to believe that the patient may be sensitive to
equine protein products (e.g., previous snake bite treated with antivenom in
which a sensitivity reaction was noted, multiple previous snakebites):
- Administer 1 gram of Solumedrol I.V. push.
- Wait 15 minutes before administering the antivenom.
- Administer the antivenom at a rate of one vial ten minutes, but be
prepared to infuse more slowly if allergic symptoms manifest.
- Be prepared to treat for anaphylaxis with epinephrine and other
vasoactive medicines.
References:
The following references are recommended for further indepth reading. This
material includes case histories, guidelines, and recent findings in elapid
literature. These should be read only after treatment has begun, and the
patient is in stable status.
- Haffkine Bio-Pharmaceutical Corporation: Lyophilised Polyvalent
Anti-Snake-Venom Serum: Directions of Use (Package Insert with Antivenom).
CSL, December 1978
- TIGER, M.E., BRECHER, E., BEVAN, D.: Cobra Bite in Philadelphia. PA
Med. 82:53, 1975.
- STUEVEN, H., APRAHAMIAN, C., THOMSON, B., HOROWITZ, L., DARIN, J.:
Cobra Envenomation: An Uncommon Emergency. Ann Emerg Med. 12:79, 1983.
- REID. H.A.: Cobra Bites. Brit Med J. 2:540, 1964.
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