This document provides an overview of snake bite management. It discusses the epidemiology, types of venomous snakes and their venom mechanisms. It outlines the signs and symptoms of snake bites, as well as first aid measures and laboratory tests. The main treatment involves administration of antivenom. Supportive treatments are also described, such as managing hypotension, acute kidney injury, haemostatic disturbances and ophthalmia. Recent research advancements involving herbal antidotes and potential medicinal uses of snake venom are also mentioned.
2. CONTENTS
1. INTRODUCTION
2. EPIDEMIOLOGY
3. CLASSIFICATION
4. TYPES
5. MECHANISM OFACTION
6. VENOM COMPOSITION
7. SIGNS AND SYMPTOMS
8. FIRST AID
9. INVESTIGATION OR LABORATORY TEST
10.MANAGEMENT
11.RECENT ADVANCEMENT
12.REFERENCE
3. INTRODUCTION
>Snake bite is frequent and devastating medical emergency and
need hospital admission .
> It is an occupational disease results in the death or chronic
disability.
About 54 types of venomous snakes are found in India
>About 15000 to 20000 deaths are reported every year in India .
> Diagnosis of the species of snake responsible for the bite is
important for optimal clinical management.
> Antivenom is the only effective antidote for snake venom.
6. Dubio’s Sea Snake
Fierce Snake
Eastern Brown
Snake
Blue Krait
Black Mamba Tiger Snake
Philippine Cobra Vipers Death Adder Rattle Snake
MOST VENOMOUS SNAKES IN THE WORLD
Taipan
7. MAJOR VENOMOUS SNAKES OF INDIA
Cobra
Common Krait
Russel’s Viper
Saw scaled Viper
N
E
U
R
O
T
O
X
I
C
H
A
E
M
O
T
O
X
I
C
9. Neurotoxins antagonistically bind tightly and noncovalently to Nm
AChRs of skeletal muscles, thereby blocking the action of ACh at the
postsynaptic membrane, inhibiting ion flow and leading to paralysis
Haemotoxins are toxins that destroy red blood cells (that is,
cause hemolysis), disrupt blood clotting, and/or
cause organ degeneration and generalized tissue damage.
MECHANISM OF ACTION OF SNAKE
VENOM
NEUROTOXIC
HAEMOTOXIC
11. SIGNS AND SYMPTOMS
(when venom is injected)
Fang mark, pain, local bleeding, bruising, burning
sensation, enlargement of lymph node, swelling.
LOCAL
SYSTEMIC
Nausea, vomiting , abdominal pain, weakness , drowsiness,
shock, hypotension, cardiac arrhythmia, visual
disturbances, pulmonary oedema.
12.
13.
14. 1.Identify the snake species if possible
2.Keep the person calm. Acute stress reaction increases blood flow
and endangers the person
3.Immediately transport the person to hospital as soon as possible
4. Do not administer stimulants or pain medications unless
specifically directed to do so by a physician.
5.Remove any items or clothing which may constrict the bitten limb if
it swells
6.Keep the person as still as possible
7.Do not incise the bitten site.
8.Bitten limb should be placed below heart level
9. Do not use tight tourniquets
FIRST AID
15. INVESTIGATION OR LABORATORY TEST
► 20-minute whole blood clotting test
► Haemoglobin concentration/haematocrit
► Platelet and WBC count
► Blood film
► Plasma/serum
► Urine examination
► Biochemical test
16. ANTIVENOM TREATMENT
► Antivenom is immunoglobulin purified from the serum or plasma
of a horse or sheep that has been immunized with the venom of
snake.
► Monovalent or monospecific antivenom neutralizes the venom of
only one species of snake.
► Polyvalent or polyspecific antivenom neutralizes the venoms of
several different species of snakes.
► The ASV that is available in India is a polyvalent type which is
active against the commonly found snakes in India including the
Favorite Four.
17. Indications for antivenom treatment
► Neurotoxicity
► ARF
► Bleeding /coagulopathy
► Myoglobinuria/haemoglobinuria
► Cardiac toxicity
► Local swelling involving more than half of the bitten limb
► Rapid extension of swelling
► Development of an enlarged tender lymph node
18. Administration of antivenom
Epinephrine (adrenaline) should always be drawn up in readiness
before antivenom is administered.
Antivenom should be given by the intravenous route whenever
possible.
Two methods of administration are recommended:
1) Intravenous “push” injection
2) Intravenous infusion
Patients must be closely observed for at least one hour after
starting intravenous antivenom administration, so that early
anaphylactic antivenom reactions can be detected and treated
early with epinephrine.
19.
20. Criteria for repeating the initial dose of
antivenom
If the blood remains incoagulable
In patients who continue to bleed
In case of deteriorating neurotoxicity or
abnormal cardiovascular signs
21. DOSE OF VENOM
SNAKE SPECIES
AVERAGE DOSE
INTIAL DOSE
COMMON KRAIT --------- 100 ml
RUSSELL’S VIPER -------- 100 ml
SAW SCALED VIPER --------- 50ml
INDIAN COBRA ---------- 100ml
22. Supportive/ancillary treatment
Antivenom treatment can be expected to neutralize free
circulating venom, prevent progression of envenoming and allow
recovery. However, these processes take time and the severely
envenomed patient may require life support systems such as
treatment of shock, assisted ventilation and renal dialysis until
the severely damaged organs and tissues have had time to
recover.
23. Treatment of hypotension and shock
Causes of hypotension and shock
1) Anaphylaxis
2) Vasodilatation
3) Cardio toxicity
4) Hypovolaemia
5) Antivenom reaction
6) Respiratory failure
7) Acute pituitary adrenal insufficiency
8) Septicemia
In patients with hypotension as dopamine may be given by
intravenous infusion, preferably into a central vein (starting
dose 2.5-5 mg/kg/minute).
Shock is mainly due to acute adrenal insufficiency due to
hemorrhage and can be treated by Hydrocortisone.
24. Treatment of oliguria and acute kidney injury
1 Oliguric phase of renal failure
Establish intravenous access.
Give fluid challenge
Insert a urethral catheter with full sterile precautions
Diuretic treatment mainly using furesemide
Biochemical monitoring
Detection and management of hyperkalaemia
Management of severe acidosis
Dialysis
25. Cont..
Prevention of renal damage in patients with
myoglobinuria or haemoglobinuria
1) Correct hypovolaemia and maintain saline diuresis (if possible)
2) Correct severe acidosis with bicarbonate
3) Give a single infusion of mannitol (200 ml of 20% solution over
20 minutes)
26. Haemostatic disturbances
1) Bleeding and clotting disturbances may occur due to the treatment
of specific antivenom.
2) Dose may be repeated several time within the interval of six hours
before blood coagulability is finally restored.
3) Heparin and antifibrinolytic agents are not used in the treatment of
snake venom.
4) Venipuncture should be avoided in the patients with haemostatic
disturbances.
27. Management of cobra spit ophthalmia
> Urgent decontamination by copious irrigation.
>Analgesia by vasoconstrictors with weak mydriatic activity (e.g.
epinephrine) and limited topical administration of local
anesthetics (e.g. tetracaine).
> Exclusion of corneal abrasions by fluorescein staining with a
slit lamp examination and application of prophylactic topical
antibiotics .
> Antihistamines in case of allergic keratoconjunctivitis.
28. RECENT ADVANCEMENT
>Researches are going on to develop a herbal antidote
against snake venom.
>Many plant species are found to be effective against the
snake venom.Some of the important examples for them
includes Worm wood, grape vine , Arsitolochia indica , amla
etc .
>Snake venom are now found to be posess anticancer and
analgesic activity.
>Venoms of cobra , Russels viper, rattle snake etc is found to
be have potent anticancer activity.
>Venom of black mamba is found to be have potent analgesic
activity .
29. REFERENCES
1) WHO guidelines for management of snake bite
2) Wikipedia
3) WHO. Guidelines for the Production, Control and Regulation of
Snake Antivenom Immunoglobulins. Geneva: World Health
Organization, 2010.
