1. The document discusses snake classification, types of venomous snakes in India, signs and symptoms of snake bites, and management of snake bites. 2. Poisonous snakes are classified based on the type of venom secreted into three families - Elapidae which secretes neurotoxic venom, Viperidae which secretes haemotoxic venom, and Hydrophidae which secretes myotoxic venom. 3. Common poisonous snakes in India include cobras, kraits, Russell's vipers, and sea snakes. Bites from kraits and Russell's vipers are more toxic than cobra bites. 4. Management of snake bites involves local treatment, administration of antivenom, and supportive care depending

1. SNAKEBITE
A.AKHIL ROYAL
KIMS MEDICAL COLLEGE
AMALAPURAM

2. Classification of snakes
Snakes can be classified into poisonous and non-
poisonous.
Poisonous snakes belong to three Families on the basis
of poison secreted :
• 1. Elapidae : Neurotoxic
• 2. Viperidae : Haemotoxic
• 3. Hydrophidae : Myotoxic

3. India: Poisonous snakes
Elapidae Cobra, Kraits Neurotoxic
Viperidae
(Vipers)
Russell’s Vipers.,
Saw scaled Vipers.,
Pit Vipers.
Hemotoxic
Hydrophidae Sea Snakes Myotoxic
In India, >200 species of snakes.
Only 52 are poisonous.
Krait and russell’s viper is much more toxic than that of cobra

4. Krait
Cobra
Pit
Viper
Rusell’s
viper

5. Difference between poisonous and
non-poisonous snakes
Points Poisonous snakes Non Poisonous
1. Belly scales Large : They cover the entire breadth of
belly
Small : They never cover
2. Head scales a) Usually small in vipers
b) May be large in pit vipers
c) Cobras and Coral snakes where third
labial touches the eye and nasal shields
d) Kraits ,where there is no pit and the
third labial does not touch the nose and
eye
Are usually large with
exceptions as outlined under
poisonous snakes
3. Fangs Are hollow like hypodermic needle Short and solid
4. Tail Compressed Not markedly compressed
5. Habits Usually nocturnal Not so
6. Teeth bite marks Two fang marks with or without marks of
other teeth
Two fang marks with number
of small teeth marks

6. Snake Venom
Combination of
Enzymes & Non-Enzymatic polypeptides.
-Acidic
-Sp Gravity: 1.030-1.070
-On drying Fine needle like crystals.
-Water Soluble.
-Lethal Dose:
Cobra-0.12gm, Krait0.06gm- Russell’s V-0.15gm

7. Vasodilators Hypotension
Coagulopathic Consumptive coagulopathy
Hyaluronidase Spread of venom
Haemolysins
Haemorrhagins
Bleeding from fang site
Myotoxins Local tissue necrosis
Neurotoxins
Muscular paralysis &
respiratory failure
Cardiotoxins
Coronary vasoconstriction
& AV block
VENOM ACTION CLINICAL FEATURES

8. Signs and symptoms
Non poisonous snakes:
 syncope
 hypotension
 sweating
 feeble pulse
 rapid,shallow breathing
 multiple teeth impressions
 no local pain or swelling

9.  A. Elapid Bite:
Local Features :
Fang marks
Burning pain
Swelling and discoloration
Serosanguinous discharge
Local symptoms are milder in comparison
to that in Viperine bite.

10. Systemic features
 Preparalytic stage:
 Vomiting
 Headache
 Giddiness
 Weakness and lethargy
 Paralytic stage:
 Ptosis.
 Ophthalmoplegia
Drowsiness
 Convulsion
 Bulbar paralysis
 Respiratory failure
 death

11. Cardiac Depression
 Cardiogenic/ Vasogenic Shock
 Systolic cardiac arrest.
COBRA envenomation
Cardiotoxicity

12.  B. Viperid bite :
 Local features : Rapid swelling at bite site
Discoloration
Blister formation
Bleeding from bite site
Pain

13.  Systemic features:
.Generalized bleeding : Epistaxis ,hemoptysis ,
hematemesis ,bleeding gums ,hematuria ,
malena , hemorrhagic areas over skin and
mucosa
.Shock
.Renal failure

14. HYDROPHID BITE (sea snake)
Myotoxic
 Local features: minimal swelling and pain
 Systemic features:
Myalgia,
Muscle stiffness,
Myoglobinuria , renal tubular necrosis.

16. DIAGNOSIS OF SNAKE BITE
 FANG MARKS: classically, two puncture
wounds seperated by a distance varying from
8mm to 4cm, depending on the species
involved.
 However a side swipe may produce only a single
puncture,while multiple bites could result in
numerous fang marks.

17. Lab investigations
20 WBCT-Test positive for viperine bite
ELISA Test
Non Specific- Hemogram, S.Creatinine, S.Amylase,
CPK, Creatine Phosphokinase,
 PT , FDP & Fibrinogen level in viper bite
interfer with clotting mechanism.
 ABG, Electrolyte-for systemic manifestion.
 Urine Examination for Proteinuria ,
Myoglobinuria

18. Metabolic changes
• Hyperkalemia in metabolic acidosis
• urine- hematuria, proteinuria, myoglobinuria
• Kidney- acute renal failure
• Chest X-ray- pulmonary edema, pleural effusion

19. ECG CHANGES IN ENVENOMATION
 Sinus tachycardia
 Sinus bradycardia
 Sinus arrhythmia
 ST depression withT wave inversion in inferior &
anterior limb

20. Factor affecting snake bite toxicity
factor effect
Body weight Bigger the size lesser toxicity
Aggravating
factor
Predispose to harmful effect of snake venom
Part bitten Bite on face and trunk are most lethal
Exercise Poor outcome
Individual
sensitivity
Sensitivity of individual to venom modified clinical outcome
Bite
characteristic
Type of bite(business or defence),Bite number ,depth, duration of when
snake clinges to body,bite through clothes,ammount of venom,condition of
fangs,different species & their lethal dose

21. MANAGEMENT

22. Management
Management
Local
Specific
Supportive

23. Management
• The first aid being currently recommended is based around the
mnemonic: “Do it R.I.G.H.T.”
R =Reassure the patient.
I = Immobilise in the same way as a fractured limb.
G.H. = Get to Hospital Immediately.
T = Tell the doctor of any systemic symptoms such as ptosis that
manifest on the way to hospital.

24. First Aids

25. Dos
• Reassure.
• Remove all rings, Bracelets from
bitten parts of the body.
• Wash the bitten area with soap and
water.
• Keep the stricken limb below the
heart.
• Immobilize the bitten limb with
splint or slings.
• Get medical help as quick as
possible.Sanjaya Gihan

26. Sanjaya Gihan

27. Do Nots
• Don’t panic
• Don’t make any cut, scratch or
incision
• Don’t suck at the wound
• Don’t apply ice packs to the
bitten area.
• Don’t use tight bands or
tourniquet.
• Don’t drink alcohol, take
herbal medicine or Aspirin.Sanjaya Gihan

28. Management: local reactions
 BULLAE - LEFT INTACT
 NECROSIS - DEBRIDEMENT
 COMPARTMENT SYNDROME - FASCIOTOMY

29. Specific treatment
Anti snake Venom
Indication for ASV
• Spontaneous systemic Bleeding
• WBCT > 20 min
• Thrombocytopenia (platelet < 1 lac)
• Shock, paralysis, ARF, Rhabdomyolysis,
Hyperkalemia.
• Local swelling involving > ½ of bitten limb
• Rapid extension of swelling

30. What is ASV?
• Antivenom is immunoglobulin purified from the serum or
plasma of a horse or sheep that has been immunised with the
venoms of one or more species of snake.
• ASV IN INDIA: Polyvalent
COBRA
KRAIT
RUSSEL’S VIPER
SAW SCALED VIPER
Potency; 1 ml ASV neutralizes:
0.6mg Cobra, 0.45mg Krait,
0.6mg Rusell’s V, 0.45mg Saw scaled Viper.
-Lethal Dose:
Cobra-0.12gm, Krait0.06gm- Russell’s V-0.15gm

31. ASV Indication:
Systemic manifestaiton
 NEUROTOXICITY
 HAEMOTOXICITY
 NEPHROTOXICITY
 CARDIOTOXICITY
 RHABDOMYOLYSIS
 REPEATED VOMITING
 Others:
-Local swelling involving more than half of the bitten
limb.
-Rapid extension of swelling.
-Development of an enlarged tender lymph node
draining the bitten limb

32. Timing of ASV
 Best effects are observed within four hours of
bite .
 Effective in symptomatic patients even 48 hours
after bite.
 Efficacious even 6-7 days after the bite from
vipers.

33. Dose
5 vials(50ml)
5-10 vials
(50-100ml)
10-20 vials
(100-200ml)

34. Repeat dose
Criteria for repeating the initial dose of
antivenom
 Persistence or recurrence of blood incoagulability
after 1-2 hr
 Deteriorating neurotoxic or cardiovascular signs
after 1-2 hr
 Continuing absorption- due to improved blood
supply following correction of shock, hypovolaemia
etc A redistribution of venom from the tissues
into the vascular space.

35. Disadvantage of ASV
• Pain at injection site
• Hematoma formation
• Increase intra compartmental pressure

36. Antivenom reactions
20% of patients, usually develop a reaction
Types:
1. Early anaphylactic reactions- within 10-180 min
2. Pyrogenic (endotoxin) reactions- develop 1-2
hours
3. Late (serum sickness type) reactions- develop 1-
12 (mean 7) days.
Fatal reactions have probably been under-
reported, as death after snake bite is usually
attributed to the venom.

37. Treatment Of Early ASV reaction
• Adrenaline -1:1000 i.m.
0.5 mg in adult
0.01 mg/kg in children
can be repeated every 5 min if necessary
H1 antihistaminic-i.v. 1 mg of CPM
I.V. Hydrocortisone

38. Treatment Of Late ASV reaction
• 5 days course of oral anti histaminic CPM
2mg/6hour-adult
0.25 mg/kg/day in divided dose
Patient who fail to response with in 24 hr
Predinisolone-
5mg/6h in adult
0.7 mg/kg/day in divided dose in children

39. ASV and children
Dose of antivenom
 Snakes inject the same dose of venom into
children and adults.
 Children must therefore be given exactly the
same dose of antivenom as adults.

40. Supportive therapy
• For Coagulopathy - if not reverse after ASV therapy
Fresh frozen plasma
Cryoprecipitate (fibrinogen, Factor VIII),
Fresh whole blood,
Platelet concentrate.

41. For Bulbar Paralysis & Resp. Failure-
• ASV alone not sufficient
• Tracheotomy, Endotrachial intubation,& mechanical
ventilation
• Inj. of neostigmine-50 to 100 microgram/kg/4hrs as
a continuous infusion
• Glycopyrrolate-0.25 mg can be given before
neostigmine in place of atropine
don’t cross blood brain barrier
• Care of bitten part-
Antibiotic prophylaxis & ATS injection