snake bite management lecture based on snakebite guidelines of India specifically west bengal 2018

1. Snakebite
Dr. Chirantan Mandal
SenioResident Medicine
AIIMS Kalyani
based on Snakebite guideline India 2018
9th October 2021

2. intro
• life threatening occupational hazard outdoor workers
• Males bitten >>more>>than females (more outdoor activity)
• most snake bite on feet and ankles
• 97% snakebites are rural (open field latrine/walking barefoot)
• snakebite peak in summer/ heavy rainfall
• 70% of all snakebites are non-venomous 50% venomousnake bites are dry
(no envenomation)
• Only 7% snakebite deaths reported in India Only 22% attend hospitals.
• 66% snakebite deaths were due krait bite

3. Epidemiology
• Snakes found everywhere except artic antartic isolated islands
• total 250 Snake species in India,
out of 250, 60 are venomous.
out of 60, 50 are seasnakes (rarely bite)
•Big 4 species account for 99% of the venomousnakebites
• 1) Spectacle Cobra
• 2) Russell Viper
• 3) Krait and
• 4) sawscaledviper 75% of bites in India (not found in WB)

4. Spectacle Cobra
Naja naja
Saw scaled Viper Echis carinatus
Russell’s Viper
Daboia russelli
Common Krait Bungerus caeruleus
Big 4

6. NEUROTOXIC
• Cobras:
• Spectacle Cobra ( Naja naja ) Gokhro
• Monocled Cobra (Naja kaouthia) Keute
• King Cobra (Ophiophagus hannah) Sankhachur.
• Kraits:
• Common Krait (Bungarus caeruleus) Kalachiti, Domnachiti
• Banded Krait (Bungarus fasciatus) Sankhamuti.
• Black Krait (Bungarus niger).
• Sind Krait (Bungarus walli).
• Coral Snakes (Calliophis maculiceps (Not found in WB).

7. Spectacled
Cobra
Naja naja
gokhro
Monocled Cobra
(Naja kaouthia)
Keute
King Cobra (Ophiophagus hannah)
Sankhachur
Krait (Bungarus caeruleus)
Banded
Krait
(Bungarus
fasciatus)
Sankhamuti.
Black
Krait
(Bungarus
niger)
Coral Snakes
(Calliophis maculiceps

8. HEMOTOXIC
• Rusell’s Viper (Daboia russelii) Chandrabora.
• Saw Scalled Viper (Echis carinatus) Pure Haemotoxic (very rare in WB)
• Humpnose Pit viper (Hypnale hypnale): Pure Hemotoxic (Only in
Western Ghats; Kerala and TN).
• Green Pit vipers (Trimeresurus gramineus): mild venom, causes local
swelling only. (Gechhobora).
• Mountain Pit Viper (Ovophis monticola) found in Darjeeling Hills of
WB. (Gurbe).

9. Russell's
Viper
(Daboia
russelii)
Chandrabora.
Saw
Scalled
Viper
(Echis
carinatus)
Saw Scalled Viper (Echis carinatus)
Green
Pit
vipers
(Trimeresurus
gramineus
(Gechhobora).
Mountain Pit Viper (Ovophis monticola)

10. NON
poisonous
Jal dhora
gharchiti
Bengal monitor lizard

11. Hele
laudoga
Bethacchra
Danras
NON
poisonous

12. pathophysiology of venomousnakebite
• 2 venom glands (modified salivaryglands connected to hollow hypodermic fangs)
inject venom into softissue, gradually absorbed via lymphatics
• Fatal dose venom (42mg Russel Viper /15 mg Cobras/ 1mg Krait)
• 90% wt of venom is biologically active proteins enzymes.
• Hemotoxic viper venoms containing procoagulant enzymes activate clotting &
stimulate fibrin formation in blood. fibrin clot is broken down immediately by
plasmin resulting incoagulable blood (consumption coagulopathy) within 30min
• postsynaptic neurotoxins Krait α-bungarotoxin & cobrotoxin both
are (irreversible nicotinic acetylcholine receptor blocker)
• AKI/ ATN direct nephrotoxicity renal tubules Hemoglobinuria

13. patterns in identifying the types of snake
• snake identification only by appearance can be misleading
• not an essential step in snake bite management.
• Current guidelines do not promote killing of snake
• Never try to catch dead / alive snake
• l̶o̶n̶g̶i̶t̶u̶d̶i̶n̶a̶l̶ ̶r̶o̶w̶s̶ ̶o̶f̶ ̶l̶a̶r̶g̶e̶,̶ ̶d̶a̶r̶k̶-̶r̶i̶m̶m̶e̶d̶,̶ ̶p̶a̶l̶e̶-
̶c̶e̶n̶t̶e̶r̶e̶d̶ ̶s̶p̶o̶t̶s̶ ̶a̶r̶e̶ ̶i̶n̶d̶i̶c̶a̶t̶i̶v̶e̶ ̶o̶f̶ ̶t̶h̶e̶ ̶R̶U̶S̶S̶E̶L̶L̶’̶S̶ ̶V̶I̶P̶E̶R̶S̶̶ ̶H̶A̶E̶M̶O̶T̶O̶X̶I̶C̶.̶ ̶ ̶
• a̶l̶t̶e̶r̶n̶a̶t̶i̶n̶g̶ ̶b̶l̶a̶c̶k̶ ̶&̶ ̶y̶e̶l̶l̶o̶w̶/̶ ̶w̶h̶i̶t̶e̶ ̶c̶i̶r̶c̶u̶m̶f̶e̶r̶e̶n̶t̶i̶a̶l̶ ̶b̶a̶n̶d̶s̶ ̶
K̶R̶A̶I̶T̶S̶-̶N̶E̶U̶R̶O̶T̶O̶X̶I̶C̶.̶ ̶ ̶
• F̶l̶a̶t̶ ̶t̶a̶i̶l̶s̶ ̶a̶r̶e̶ ̶u̶s̶u̶a̶l̶l̶y̶ ̶s̶e̶a̶ ̶s̶n̶a̶k̶e̶s̶

14. Don’ts after snakebite occurs
• Do NOT waste time in traditional first aid methods
• Do NOT apply a tourniquet.
• Do NOT apply pressure cold compresses
• Do NOT cut into with a knife or razor
• Do NOT try to suck out the venom by mouth or
• Do NOT wash the snakebite wound
• Do NOT attempt to kill or catch the snake

15. Death in untreated snakebites
• If death within 1st hr of bite mostly due to like old age cardiac causes
• takes few hours for untreated neurotoxic elapid (cobra/krait) to succumb
• several days for a untreated viper
• traditional healers/transportation problems
• inadequate artificial ventilation / Late dialysis
• to treat hypovolemia shock / airway obstruction
• complicating infections (fasciitis/ extensive cellulitis)

16. First Aid Treatment
• both tourniquets and Pressure
Immobilization Method are
discouraged in India since it needs
skilled medical or paramedical
person to be present at the site of
accident PRACTICALY IMPOSSIBLE

17. First AID do it RIGHT
• REASSURE patient panicked tachycardia spreads venom rapidly.
70% snakebites nonvenomous. 50% of venomousnake bites dry
• IMMOBILIZE the bitten limb in the same way as a fractured limb.
• GO HOSPITAL immediately.
• TELL DOCTOR of any progress/new symptoms such as ptosis that

18. Don’t look for bite marks
• Bite marks pattern cannot differentiate
venomous/nonvenomous.
• fang marks pattern cannot ascertain the amount of
venom injected, severity of systemic poisoning and
nature of neurotoxic/hemotoxic
• bite from venomous snake may show one or more
punctures

19. signs / symptoms of Viper (Hemotoxic) envenomation
• Progressive swelling & local pain/necrosis/blistering
• Epistaxis / bleeding from the gum and other orifices.
• Vomiting + Acute abdominal pain (may GI bleed).
• Hypotension (due to hypovolaemia / direct vasodilation).
• early AKI (renal failure) hematuria reduced/ nil urine output.
• skin petechiae, purpura, and ecchymosis.
• Lateralising neurological symptoms and asymmetrical pupils
(intra-cranial bleeding)
• conjunctival oedema, sub-conjunctival haemorrhage

21. Signs/symptoms of Neurotoxic envenomation
• cranialnerves paralysis (ptosis, gaze fatigue, diplopia, ophthalmoplegia)
• pharyngeal palsy (paralysis of jaw ± tongue causing upper airway obstruction
• aspiration of pooled secretions (patient’s inability to swallow)
• Numbness around lips/mouth, bulbar paralysis, respiratory failure
• Early morning stomach pain (submucosal hemorrhage) commonest in Krait
• Krait bite often in early morning, resultant paralysis often mimmics stroke.
• inadequate ventilation cause cyanosis, alteredsensorium coma.
• Paradoxical respiration (intercostal muscles becoming paralyzed)
• Neuroparalytic Cobra bites symptoms typical present within 30 min– 2 hours
• Krait bite symptom presents within 3 – 24 hours

23. 5D and 2P Neurotoxic envenomation
• dyspnea, dysphonia, dysarthria, diplopia, dysphagia, ptosis, paralysis
• Furrowing of forehead ➜ Ptosis ➜Diplopia ➜ Dysarthria ➜
Dysphonia ➜ dyspnea ➜ dysphagia
• 3rd , 4th , 6th and lower cranial nerve paralysis.
• paralysis of intercostal/ diaphragmatic paralysis in descending manner
• absent DTR and head lag heralds impending respiratory failure
• stridor, ataxia may be seen.
• Bilateral dilated, poorly or a non-reacting pupil is not the only sign in
brain death in elapid (neurotoxic) envenoming

24. Late-onset envenoming
The patient should be kept under close observation for at least 24 hours
Krait and the Hump-nosed pitviper (not present in WB)
can take upto 12 hours for symptoms to manifest.
Late onset envenoming is a well-documented occurrence.

25. compartmental syndrome (Russel viper bite)
• Compartment syndrome is diagnosed with 5P
• Pain (severe) on passive movement
• Pallor
• Paresthesia
• Pulselessness
• Paralysis or weakness of compartment muscle.

26. Signs & symptoms of Snake bite

27. Diagnosis and testing
• Progressive local swelling is the commonest sign of envenomation
• local swelling, painful tender, persistent bleeding from the bite wound, epistaxis,
hematuria, ptosis and other signs of paralysis
• cannot use Glasgow Coma scale to assess (if paralyzed by neurotoxic venom)
• Monitor the patient every 2 hourly. Pulse rate, respiratory rate, BP and
• In case of viper bites (hemotoxic) signs of coagulopathy do 20WBCT
• 20minwholebloodclotting (20WBCT) every hr for 1st 3h / every 4h next24h
• pain movement, pallor, pulseless limb, hypoesthesia (compartment syndrome)
• ptosis, hoarseness of voice, respiratory failure (in Cobras & Kraits)

28. 20minute Whole Blood Clotting Test (20WBCT)
• New dry glass testube/vial (not Plastic)
(not cleaned with detergent, else wall may not activate factorXI to clot)
• draw 3ml blood, keep 20min in testube undisturbed room temperature
[normal clotting time is 8 min maximum
• 20min later gently tilt the tube If the blood is still liquid (not clotted) it`s coagulopathy
confirms hemotoxic viper bite (coagulopathy not seen in neurotoxic Cobras or Krait)
• If 1st 20WBCTest is “clotted” repeat every hour 1st 3h, thereafter every 6hr
• In coagulopathy, there may be continuous oozing from bite site/gum.
May lead to hemoptysis and hematuria and ultimately AKI. (In Chandrabora bite there
would be Ptosis also).

31. Management of Snakebite INITIALS
• Admit all cases with history of bites (Snake/unknown)
for observation for a minimum of 24 hours
• Secure ABC Airway, Breathing and Circulation.
• observe for any sign of local or Systemic envenomation.
• 50% of known venomous snake bite are dry bite no envenomation
• If no indications for administration of AVS, (don’t give AVS)

32. following local treatments are contraindicated
• Washing X
• Antiseptics. X
• Incision. X
• Suction. X (DON’T EVEN THINK ABOUT THIS)
• Electrotherapy or Cryotherapy. X
• Venom Stone.X

33. Important don’ts
• Don't kill/catch snake (dangerous) & not essential for management.
• Don't wash wound may introduce infection,
increase absorption of venom
• Don't inject antisnakevenom (ASV) locally (it’s designed for IV)
• Don't tie tourniquets increase risk of ischemia/limb gangrene
• Cutting the biting site. No venom is removed by this.

34. Patient Assessment
• identifying the snake (not essential) (20WBCT indirectly helps)
• Ruleout any possible use of traditional medicines
• Take history of exact time of the bite. indicates progression symptoms
• Ask what the victim was doing at the time of the bite. grass cutting or
feeding stock animals in the evening can be suggestive of snakebite.

35. Management of Bite Pain
• severe pain at the bite site. use paracetamol
• Don’t use NSAIDs (avoid aspirin) cause bleeding in coagulopathy
• Mild opiates Tramadol can be used orally for relief of severe pain.
• Never remove tourniquet in ER. test for pulse distal to the tourniquet
before removal. If occluded the distal pulse, then a BP cuff can be
applied to reduce pressure slowly
• Sudden removal can lead to a massive surge of venom leading to
neurological paralysis, hypotension due to vasodilation, sudden
respiratory distress or hypotension.
Handling Tourniquets

36. Anti-snake Venom Serum (ASV)
• Indian Polyvalent Anti Snake Venom Serum is a unique solution to all big 4
venomous snakebite cases in India.
• called polyvalent, can be used to treat most types of snakebites.
• species specific Monovalent AVS is not available in India.
• 4 types of snakes are used to prepare this AVS. These snakes are
• 1) Indian Spectacle Cobra 2) Russell Viper 3) Krait and 4) sawscaledviper.
• Sub lethal dose of venom of all these four snakes are injected to a horse (to
hyper immunize). Antibody (Ig G) develops against these snake venoms in
the blood of that horse. This horse blood (plasma) is then purified in the
laboratories to prepare Polyvalent AVS. AVS is basically a horse protein, and
has every chance to be rejected by our human body, as a foreign protein..

37. Anti-snake Venom Serum (AVS)

38. Anti-snake Venom Serum (AVS) essential
• Give 0.25 ML Inj. Adrenaline S/C premedication.
• No prior AVS skin test required since patient is in danger either way
• 10vials AVS reconstituted in 100ml of distilled water
use 400ml NS given over 1hr adult
use 200ml NS given over 30min children to avoid fluid overload
• Initial 10vial AVS for Adults/children/Pregnant/hemotoxic/neurotoxic
must to neutralize venom as snakes inject the same amount regardless
• AKI patient can use infusion pump full dose ASV undiluted over 30 minutes.
• intracranial bleeding may require lifesaving surgery. coagulation must be
restored to avoid bleeding and can give up to 30 vials ASV

39. Criteria for Administration of AVS
• Use AVS any evidence of envenomation or progressive swelling.
• viper coagulopathy detected by 20WBCT or visible spontaneous bite
site bleeding
• Cobra/krait neurotoxicity- ptosis,ophthalmoplegia,paralysis, inability
to lift head
• ASV should be administered over 1hr, not longer
• ASV must NEVER be given by the IM route (poor bioavailability)
• NEVER inject the ASV locally at the bitesite

40. Signs of recovery (AVS is working)
• if adequate dose of AVS has been administered
• spontaneous systemic bleed (gum bleeding) usually stops within
15–30min. Blood coagulability is usually restored in 6 hours
• Post synaptic neurotoxic envenoming (Cobra) may improves early
• Presynaptic neurotoxic envenoming (Krait) bite usually takes several
hours to improve.
• blood pressure recover in shocked patients

41. Repeat doses of AVS
• In Viper bites, once initial 10vials of AVS over 1 hour
no further AVS is required for next 6 hours don’t hurry wait
• liver needs 6hours to restore clotting factors.
• 6hr later if 20WBCT +ve repeat 2nd dose of 10vials AVS immediately.
• If no active bleeding, keep repeating 20WBCT test every 6 hours
• 6hr later if 20WBCT –ve (blood clots) no need to give AVS any further
• regardless viper/cobra bites maximum 30vials of AVS is needed/given
• No AVS after 30 vials.

42. Monitoring/ General Workup
• Monitor Pulse, respiratory rate, blood pressure hourly
• urea, creatinine, WBC count K+ level Urine output, urine RBCs in viper
Monitor Vomiting, diarrhea, abnormal bleeding.
• Look for Extent of local swelling and necrosis

43. Management of Neurotoxicity
• post-synaptic neurotoxins (Cobratoxin / krait α-bungarotoxin) both
are (irreversible nicotinic acetylcholine receptor blocker)
• Neostigmine (anticholinesterase) prolongs / increases acetylcholine
• Atropine reversibly blocks muscarinic acetylcholine receptors
• reverses respiratory failure and neurotoxic symptoms
• particularly effective for post-synaptic neurotoxins (Cobra/krait)
• not useful against / not needed in Russell Viper
• Pralidoxime cholinesterase regenerator no role in snakebite

44. atropine/neostigmine in neurotoxic bites
• 1stdose AVS ➜1st (Inj.IV Atropine 0.6mg) then ➜ ANtrial
Neostigmine trial (1.5mg IM) ➜ monitor victim closely for 1st hr
• Improvement by atropineostigmine indicates Cobra bite
• pediatric (neostig loading dose 0.04mg/kg IM) (atropine is 0.05 mg/kg)
• after 30min 1st visible improvement in ptosis
if ptosis recovers ≥50% within 1st hour then it’s a +ve response
If ANtrial is positive, repeat 5 doses inj.neostigmine 0.5 mg IM every 30min
with 0.6mg of atropine IV every 8hr continuous infusion.
• (pediatric, repeated 5 doses Inj. Neostigmine IM 0.01 mg/kg every 30min)

45. methods to assess response of AN trial
• Single breath count
• Length of time upward gaze can be maintained
• Stop Atropine neostigmine (ANtrial) dosage schedule if:
• Patient has completely recovers from neuroparalysis.
• side effects fasciculation / bradycardia
(signs of neostigmine overdose) (℞ 0.3 mg atropine IV stat).
• If there is no improvement after 3 doses

46. atropineostigmine caveats
• no improvement in 1st hr / worsen then give 2nd/final dose atropineostigmine
• If neurodeficit persist/ no improvement dspite 2nd dose atropineostigmine
shift patient to mechanical ventilation. Repeat 2nd dose of 10 vials AVS
this also indicates Krait bite
Calcium Gluconate in Krait bites
• Krait affects pre-synaptic fibers (Ca+2 acts as neurotransmitter.
• Give Inj. Calcium gluconate 10ml IV (pediatric 1-2 ml/kg) slowly over 5-10 min
every 6hr for next 24hr. (krait neuroparalysis recovers within 5-7 days)

47. Broken neck sign

48. Renal failure = AcuteKidneyInjury = AKI
in hemotoxic viper bite
• abnormal 20WBCT (not clotted) in viper bites indicates coagulopathy,
give 1stdose of 10 vials AVS ➜ confirm hematuria/abnormal creatinine
➜refer/send patient to dialysis facility
• Can give undiluted ASV full dose infusion pump over 30min in AKI
• AKI mainly due to intravascular haemolysis, DIC, direct nephrotoxicity,
hypotension rhabdomyolysis.
• Very early AKI in Russell viper bite (within 1hr post bite)
• Suspect AKI if falling/nil urine output
creatinine > 5 / Urea >200 / K+ > 5.6 / metabolic acidosis on ABG

49. Referral criteria for Neurotoxic envenomation
• AVS alone cannot save life of a patient with bulbar and respiratory paralysis.
Death may result from aspiration, airway obstruction or respiratory failure
• If neuroparalysis progresses in a Neurotoxic Envenomation transfer patient
by ambulance with life support (Battery operated Transport Ventilator run by
qualified staff ) to tertiary center for mechanical ventilation resuscitation bag
in ambulance (only as last resort)
• ‘lift neck’ to elicit broken neck sign (heralds respiratory failure, needs
ventilator) immediately refer the patient
• declining single breath count, pooling of saliva indicate descending paralysis
• SpO2 <90% patient needs ventilator

50. REFERRAL CRITERIA for hemotoxic envenomation
• If no ASV available, transfer to a hospital (where it’s available)
• If 20 WBCT (not clotted) despite 1st loading dose of 10vials ASV
& patient continues to bleed➜transfer to a tertiary care medical college
• confirm hematuria/AKI ➜refer/send patient to dialysis facility
• Compartment syndrome
• Progressive septicemia

51. Forced Alkaline Diuresis trial to prevent AKI/ATN
• trial of forced alkaline diuresis within 1st 24hr of bite to avoid
pigment nephropathy (acute tubular necrosis)
• Sequence of FAD each 2 1/2 hr cycle
1st Furosemide40mg IV ➜ (500ml NS with 20ml NaHCO3/20min) ➜
(RL500 ml RL with 20ml NaHCO3/20min) ➜
(500ml 5%D with 10ml KCL/90min) ➜ Mannitol150 ml IV/20min
• 3ml/min urine output is expected, in response to 1st cycle
continue for 3 cycles
• FAD converts olig to polyuria (prevent ATN/AKI avoid dialysis >75%)
Delayed FAD has no role
• If unresponsive to Furosemide40mgIV➜discontinue FAD and refer to
dialysis centre

52. Indications for dialysis are
• urea >130 BUN > 100 Creatinine > 4 mg K+ >7
• daily rise urea>30 /BUN>15 / Creat>1/ K+ >1
• daily HCO3 fall >2
• pulmonary oedema
• Uremic encephalopathy, pericarditis

53. coagulopathy specific management
• prolonged CT, PT, aPTT administer fresh frozen plasma (FFP) infusion
FFP administration after 1st ASV rapidly restores clotting function in
most FFP 10-15 ml/kg over 60min given within 4hr of 1st ASV
target INR < 2.0, at 6hr after 1st FFP
• low platelets indicates consumption coagulopathy and DIC
• Low fibrinogen/high FDP will require fibrinogen/FFP infusion
• PCV > 30% must be maintained. measure serial PCV every 6hr
packed cell PRBC transfusion If anemia PCV < 30
• Avoid intramuscular injections in hemotoxic bites

54. Celullitis / swelling specific management
• Routine antibiotic not necessary, consider only if cellulitis or necrosis.
• cellulitis give amoxiclav/metronidazole/ceftriaxone after completion
1st 10 vials ASV
• swelling of the limb after bite can be successfully managed by
repeated MgSO4 + glycerin compresses (thrice dailyx 7 days)

55. ASV adverse drug reaction (adr)
• Before starting AVS always Premedicate 0.25ml Adrenaline S/C
most AVS reactions are prevented
• monitor patient closely for many anaphylactoid reactions
like urticaria, itching, fever, vomiting, diarrhea, cramps, tachycardia,
hypotension, bronchospasm angioedema
• At any sign 1st stop AVS drip temporarily
Give 0.5 ml (1:1000) Adrenaline IM (pediatric 0.01 mg/kg)
repeat 2nd dose If no improvement/worsening within 15min
• use oxygen/ fresh IV set/500ml NS + 100mg hydrocortisone Promethazine
• Post recovery 1st restart ASV 15min slowly then resume normal drip rate

57. DISCHARGE
• Nonvenomous bite with zero symptoms/signs discharge after 24hr
• if ASV was infused discharge after 48hr
• snakebitten victim discharged from hospital must follow up.
• serum sickness (fever, joint pain/swelling) upto 5-10 days after AVS
• Patient must return if bleeding, worsening of pain, swelling,
difficulty in breathing, altered sensorium, reduced urine output

58. Tourniquet trivia
• 1st blood drawn from the patient should be typed and cross-matched,
as the effects of both venom and ASV can interfere with later cross-
matching.
• before removal of the tourniquet, find for pulse distal to tourniquet.
In confirmed venomous bite, remove tourniquet only after starting of
1st loading dose of ASV and keep Atropine Neostigmine injection
ready.

59. Thank you

60. .
Suspect Haemotoxic envenomation
• If there is definite history of viper
bites or signs of abnormal bleeding
or 20WBCT test comes ‘not
clotted’ indicating coagulopathy,
refer the case to a Hospital having
facility of kidney function test/
dialysis.
• 2. Repeat another 10 vials of AVS in
fluid in jet if active bleeding
persists (this should be done
before referral).
Suspect Neurotoxic envenomation
• 1.A Neostigmine test (AN trial) is
administered using Atropine and Neostigmine
as per dosage described earlier.
• 2. Observe the patient closely for 1 hour to
determine if the neostigmine is effective. a. If
the response (AN trial) is positive, repeat dose
of neostigmine 0.5 mg IM every 30 minutes
for 5 doses with 0.6 mg of atropine IV over an
8 hour period by continuous infusion. b. If
after 1 hour the victim has not improved or
has worsened then a second and final dose
(of Both Atropine and Neostigmine should be
given.
• 3. If no improvement even after 2nd 4. Repeat
2nd dose of Atropine and Neostigmine, the
patient will require mechanical ventilation.
• 4.Repeat 2nd dose of 10 vials of AVS & Refer to
higher center having Ventilator facility

61. REFERRAL CRITERIA:
Suspect Haemotoxic envenomation
• Once AVS is finished and adverse
reaction if any is dealt with
• Active bleeding persist
• The 6 hour rule ensures that a six
hour windowis now available in
which to transport the patient.
• If haematuria present or kidney
function test result is abnormal-
may be transfer for dialysis.
Suspect Neurotoxic envenomation
• Progressive neuroparalysis - transfer with life
• support in ambulance for mechanical ventilation
• The key criteria to determine whether respiratory failure,
requiring mechanical ventilation is likely, is the ‘neck lift’ to
elicit broken neck sign.
• Other tests which indicate descending paralysis are declining
single breath count, pooling of saliva.
• The primary consideration is to be equipped toprovide
respiration support to the victim
• Transfer the patient with a face mask, resuscitation bag and a
person, other than the driver of the vehicle, who is trained of
how to use these devices. If respiration fails then the victim
must be given artificial respiration until arrival at the institute

62. Instructions while referring
• Give prior intimation to the receiving center using available communication
facilities. Transport in an ambulance equipped with transport ventilator. If
ventilator is not available, tight-fitting face mask connected to an anaesthetic
(Ambu) bag should be available. However, do not waste time to get an ideal
ambulance.
• If ASV is not available at First contact center transfer to the nearest health facility
where ASV is available (confirmed by telephone).
• Transfer to a higher health facility (Secondary Care Hospital or Tertiary Care
Hospital) where mechanical ventilator and dialysis facilities are available for
ventilation and dialysis, if required after completion of ASV infusion only.
• During transfer, continue life-supporting measures, insert nasogastric tube and
provide airway support with the help of an accompanying staff, if required.

63. Points to be mentioned in Referral Note
Suspect Haemotoxic envenomation
• Site & time of bite Initial
symptoms
• - 20 WBCT result – initial &
subsequent
• - Total AVS dose administered
with time of each dose
Suspect Neurotoxic envenomation
• Atropine & Neostigmine – doses
& time, if given - Supportive
treatment given including blood
• - Condition at the time of
referral and reason of referral

64. Basic Minimal & Essential Drugs/ Equipment
profile for primary care
• Drug:
• AV/ ASV (in domestic fridge if liquid) Adrenaline v Neostigmine
Atropine v Hydrocortisone Antihistaminics (injectables) Analgesics o
Paracetamol o Tramadol (both oral & injectable)
• NS bottles Antibiotics o Inj Amoxicillin+ clavulanic acid o Inj
Metronidazole o Inj Ceftriaxone
• Equipment o Syringes o IV set o Clean new Glass Test tubes o Blood
pressure monitor o AMBU Bag with mask
• Other desirables o Oxygen o Laryngeal tube with laryngeal mask airway
(LMA) o Nasopharyngeal Airways (these can be improvised using size 5
Endotracheal tubes cut to the required length)

65. Anti-snake Venom Serum (ASV)
• Hump nose pit vipers are quite exceptional in India. Their venom is not responsive to common AVS. As these
snakes are limited to a small geographic area (Western Ghat hill areas), few laboratories prepare specific
Polyvalent AVS including Pit viper snake venom along with other four snakes as mentioned earlier. Indian
Polyvalent AVS is available in 10 ML vials; both in liquid and lyophilized form. Liquid ones have to be kept in
the domestic refrigerators (2-8 o
• 25 o C ). No AVS can be freezed.
• Lyophilized AVS is to be dissolved into 10 ml of water for injection just before mixing in the IV fluid for
infusion. Usually Lyophilized AVS lasts for 5 yrs and liquid ones last for 2 – 3 yrs. Both must be discarded if any
precipitate is noted before mixing in the IV fluid.
• 31 C); Lyophilized AVS can be stored in room temperature ( belowOne vial of 10ml AVS is meant for
neutralizing 6 mg of Russell’s Viper venom, 6mg of Cobra venom, 4.5 mg of Common Krait venom and 4.5mg
of Saw scaled viper venom.
• Indian polyvalent AVS has some cross sensitivity to other species of snakes also; Spectacle cobra venom AVS
has good neutralizing effect on Monocled cobra and King cobra venom. Common Krait venom AVS can
neutralize Banded Krait venom also. AVS for sea snake venom is not available in India. Some authorities
recommend high dose of Indian polyvalent AVS for sea snake bite cases in India. Many Indian laboratories
prepare AVS for commercial use; all of them have to be standardized from the Central Research Laboratory of
Govt. of India, situated at Kasauli, Himachal Pradesh.
• Is SKIN Test before administering AVS recommended ? — NO
• AVS test doses have been abandoned. They have no predictive value in anaphylactoid or late serum reactions
and may pre-sensitize the patient to the protein. This test is mostly false negative

66. Do’s after snakebite occurs
• Call ambulance and transfer patient to a medical health facility. Arrange transport of the
patient to medical care as quickly, safely and passively as possible by vehicle ambulance,
boat, bicycle, motorbike, stretcher etc.
• – Keep the person calm. Reassure them that bites can be effectively treated in an
emergency room. Restrict movement.
• – Remove any rings or constricting items, because the affected area may swell. – Create a
loose splint (it should be capable of inserting one finger beneath) to help restrict
movement of the area.
• – Ideally the patient should lie in the recovery position (prone, on the left side) with
his/her airway protected to minimize the risk of aspiration of vomitus.
• – If the area of the bite begins to swell and change colour, the snake was probably
venomous.
• – Monitor the person’s vital signs — temperature, pulse, rate of breathing, and blood
pressure — if possible. If there are signs of shock (such as paleness), lay the person flat,
raise the feet about a foot, and cover the person with a blanket