snakebite

1. Dr.Zatul Rathiah Bt. Abdul Razak
Emergency Physician UD54
Emergency & Trauma Department
Hospital Queen Elizabeth

2. Classifications
• Elapidae - Neurotoxins
• Hydropiidae - Myotoxins + Neurotoxins
• Viperidae - Hematotoxins
“ Every New HouseMan’s life
Very Happening”

3. ELAPIDAE
• short fixed front (proteroglyph) fangs
• relatively long, thin, uniformly-coloured
snakes with large smooth symmetrical scales
(plates), on the top (dorsum) of the head.
• Some, notably cobras, raise the front part of
their body off the ground and spread and
flatten the neck to form a hood
• This family includes cobras, king cobra, kraits,
coral snakes

4. COBRAS
- Ular tedung
Naja kaouthia
(Mocellate cobra)
Naja naja
(Spectacled cobra)

5. King Cobra (Ophiophagus hannah)
- ular tedung selar
Large occipital
scale

6. Kraits (genus Bungarus)
Common krait (Bungarus
caeruleus)
Malayan krait (Bungarus
candidus)
White ventral

7. HYDROPIIDAE (Sea Snake)
•Flattened paddle-like tail of sea
snakes
•Short anterior fangs
(solenoglyph)
Enhydrina Schistosa

8. VIPERIDAE
vipers (Viperinae) pit vipers (Crotalinae)
• special sense organ, the
loreal pit organ, to detect
their warm-blooded prey.
This is situated between the
nostril and the eye
Distinct triangular head
Long anterior fangs
Calloselasma rhodostoma
- Ular kapak bodoh

9. Identify snake by it’s external appearance/
match with pictures
Look for fangs (use forceps)
*fang marks- 2 prick marks ~ 1.25- 2.5cm apart
Absent: non-venomous
Present: Venomous
Short anterior fangs Long Anterior Fangs
Flat oar-like tail Large shield
scales on head
Distinct triagular head
Hydropiidae
(Sea Snakes)
Elapidae (cobras, kraits,
coral snakes)
Viperidae (Vipers)

12. Local symptoms and signs
• fang marks
• local pain
• local bleeding
• bruising
• lymphangitis (raised red lines tracking up the bitten
limb)
• lymph node enlargement
• inflammation (swelling, redness, heat)
• blistering
• local infection, abscess formation
• necrosis

13. Fang marks 2.5cm apart
Persistent bleeding
Swelling, bruising,
blistering
Tissue necrosis

14. symptoms
General
• Nausea, vomiting, malaise, abdominal pain,
weakness, drowsiness, prostration.
Hematotoxins (Viperidae)
• Visual disturbances, dizziness, faintness,
collapse, shock, hypotension
• cardiac arrhythmias, pulmonary oedema

15. Hematotoxin
• Spontaneous systemic bleeding
Bilateral chemosis
(conjunctival oedema)
Hemoptysis
Intracranial
bleeding
Spontaneous
Gum bleeding

16. Neurotoxins
• Drowsiness, paraesthesiae
• abnormalities of taste and smell
• “heavy” eyelids - ptosis ,external
ophthalmoplegia
• paralysis of facial muscles and other muscles
innervated by the cranial nerves
• nasal voice, aphonia
• regurgitation through the nose,
difficulty in swallowing secretions
• respiratory and generalised flaccid paralysis.

17. Myotoxins
• Generalized pain, stiffness and
tenderness of muscles
• Trismus
• Skeletal muscle breakdown
• Myoglobinaemia and myoglobinuria develop 3–8
hours after the bite  Acute renal failure with
hyperkalemia within 6-12hours
• Respiratory & cardiac arrest

18. cobra-spit ophthalmia (eye injuries
from spitting cobras)
• intense burning, stinging pain, followed by
profuse watering of the eyes with
• production of whitish discharge, congested
conjunctivae, spasm and swelling of the
eyelids, photophobia, clouding of vision and
temporary blindness

19. Managements of snake bite
First Aid
Transport to hospital
Hospital treatment

20. First aids
• 1st responder 
If the area is unsafe for the rescuer or the victim, move
the victim to a safe location if it is safe to do so.
• Reassure the victim
• Immobilize the whole of the patient’s body
• Suction???
Do not apply suction as first aid for snakebites . Suction
does remove some venom, but the amount is very
small. Suction has no clinical benefit and it may
aggravate the injury.
Reference : AHA 2010 part 17 – First Aid

21. • Avoid any interference with the bite wound
• Applying pressure immobilization bandage:
 40 and 70 mm Hg in the upper extremity
 55 and 70 mm Hg in the lower extremity
* effective and safe way to slow the dissemination of
venom by slowing lymph flow
@Apply a constricting band proximal to the wound –
loose enough to admit a finger between the band
and the area of wound (applied in 30min of bite)
• Try to get the snake identified/bring it along (make
sure it is dead!)
~Reference: AHA 2010 part 17 – First Aid ~

22. Transport to Hospital
• where they can receive medical care
(dispensary or hospital) as quickly
• Any movements reduced to an absolute
minimum to avoid increasing the systemic
absorption of venom
• If possible, patients should be placed in the
recovery position, in case they vomit

23. Hospital treatment
• Triage
• Airway
• Breathing (respiratory movements)
• Circulation (BP, PR, arterial pulse)
• Disability of the nervous system (level of
consciousness)
• Exposure and environmental control

24. Physical examination
• Examination of the bitten part
- extent of swelling, tenderness, local LN
enlargement, blistering, necrosis
• General examination
- Skin and mucous membrane – petechiae,
purpura, ecchymoses
- Abdominal tenderness- abd/retroperitoneal
bleeding
- Loin pain – acute renal ischemia (Russel’s
viper)

25. • Generalised rhabdomyolysis
– Painful active and passive movements
– Myoglobinuria
• Neurotoxic envenoming: Bulbar and respiratory
paralysis
– Ptosis
– Opthalmoplegia
– Trismus
– “Broken neck sign” : muscle flexing
the neck maybe paralyzed

26. Initial managements
• Close VS monitoring
• Oxygen supply
• IV cannula
• Input output charting
• Blood and urine investigations
• Circulation chart of bitten limbs – documentation &
marking of level and size of swelling
• Release the constricting band after IV cannula inserted ,
full monitoring attached to patient, and resuscitation
equipment available
* to anticipate sudden envenomation

27. Investigations
• FBC
• BUSE/ Creat
• Coagulation profile
• ABG
• UFEME
• Urine myoglobin
• Serum creatinine phospokinase
• 20min WBCT
* Warning: Arterial puncture is contraindicated in patients
with haemostatic abnormalities (Viperidae and some
Australasian Elapidae)

28. Medications
• IV Hydrocortisone
• Antihistamine/ IV chlorphenamine
• ATT
• Analgesic
• Consider Anti-venoms (accd to grade of
envenomations)

29. antivenom
• Antivenom is immunoglobulin G purified from
the serum of plasma of a horse or sheep that has
been immunised with the venoms of snake.
• If the biting species is known, the ideal treatment
may be with a monovalent (monospecific)
antivenom.
– less expensive
– administration of a lower dose of antivenom protein
• If species unknown, polyvalent antivenom should
be given.

34. Grades of envenomation
MINIMAL
• No pain to moderate pain, erythema, oedema 2.5- 15cm
• No systemic symptom
• ANTI VENOM : NOT INDICATED
MODERATE
• Severe pain, tenderness, petechiae, oedema 25-40cm
• , vomiting, fever and weakness
• ANTIVENOMS: 2-4 VIALS (20-40 mls)
SEVERE
• Widespread pain, oedema 40-50cm, ecchymosis
•++systemic signs
• ANTIVENOMS : 5 – 9 VIALS (50-90 mls)
VERY SEVERE
• Rapid swelling, Ecchymosis
• CNS symptoms , Visual disturbances, Shock , convulsion
• ANTIVENOMS : 10 -15 VIALS (100-150 mls)

35. Method of administration
• Dilute required antivenom in 200cc NS/D5% ,
slow IVD run over 1 hour
• Close monitoring of vital sign, clinical sign and
symptoms
* Watch out for anaphylaxis – prepared with
adrenaline injection

36. Criteria to repeat Antivenom?
• Persistent or recurrence of blood
incoagulability after 6 hours
• Persistent bleeding after 1-2 hours
• Deteriorating neurotoxic or CVS signs after 1-2
hours
* watch out for recurrence phenomenon after
clinical improvement

37. Antivenom reactions
• Early anaphylactic reactions (10-180min)
• Pyrogenic / endotoxin reaction (1-2H)
• Late serum sickness reaction (Develop 1-
12days, mean 7 days after treatment)

38. Questions ?
• All sea snakes in Malaysia are venomous?
- YES. All 14 species of fresh water snakes are
harmless but all 22 species of seasnakes are
venomous
• All venomous snakes bite are painful ?
- NO. Sea snakes bite are painless, with minimal
local sign normally
• All venomous snakes bite cause envenomation?
- NO. 50% of the bite are “dry bite”

39. Referrence
• Guides to essential in Emergency Medicine by
Shirley Ooi
• WHO guidelines for snake bite 2010
• Malaysian Clinical protocol snake bite 2008
• Emergency medicine by Tintinalli