SNAKE BITE (INDIAN SCENARIO)

►    3500   SPECIES

►    300     VENOMOUS
►    30000  - 40000 DEATHS ANNUALLY


POISONOUS SNAKES
INDIAN SCENARIO
►    5 DANGEROUSLY POISONOUS SNAKES
          KING COBRA
          COMMON COBRA
          COMMON KRAIT
          RUSSELL’S VIPER
          SAWSCALED VIPER
MOST COMMON POISONOUS SNAKE IS COMMON KRAIT

►    216  SPECIES

►    52  VENOMOUS



SNAKE VENOM
►    Toxic saliva secreted by modified parotid glands of a venomous snake
►    Amber coloured when fresh
►    Constituents               Toxins
                                       Enzymes
                                       Miscellaneous : neurotoxins
                                                                cardiotoxins
                                                                hemolysin


VENOM CLASSIFICATION
►    Neurotoxic              elapids(cobra,krait)
►    Hemotoxic               viperidae
►    Myotoxic                  sea snake
►    Krait and russell’s viper is much more toxic than that of cobra


SYMPTOMATOLOGY OF NON VENOMOUS SNAKES
►    Universal fear associated induce a state of shock
►    Bite site may demonstrate multiple teeth impressions
►    Lack of significant local pain or swelling
►    Adequate reassurance and symptomatic treatment measures lead to full recovery


SYMP..VENOMOUS SNAKE BITES
►    ELAPID BITE
►    Local features :
►        indistinct fang marks ,
►        burning pain,
►        swelling and discolouration,                                                                        
►        serosanguinous discharge

       
Systemic features

►    preparalytic stage  :     emesis,
                                             headache,
                                              LOC.
      paralytic stage      : ptosis,
                                           ophthalmoplegia
                                           drowsiness,
                                           dysarthria,
                                           dysphagia,
                                           convulsions,
                                           bulbar paralysis,
                                           resp failure .

     

VIPERID BITE

Local features:
                         rapid swelling,
                         discolouration,
                         blister formation,
                         bleeding from bite site,
                         severe pain
    
Generalised bleeding manifestations.                       
                          epistaxis,
                          hemoptysis,
                          bleeding gums
                          hemauria
                          purpuric spots
 Renal failure

      

HYDROPHID BITE

►    Local features: minimal swelling and pain
►    Systemic features: myalgia muscle stiffness
                  myoglobinuria , renal tubular
                  necrosis                  


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.
►    Baileys method
  
      



Management of snake bite

FIRST AID

►    DELAY ENRY OF VENOM
►    TOURNIQUET
►    ABOVE KNEE
►    ABOVE ELBOW


CLINICAL ASSESMENT
►    VITAL SIGNS—PULSE
                           --B P
                           --RESPIRATION –SBC
OBSERVE – BITE MARK
                   --LOCAL REACTION
                   --PAINFUL LNE
►               


NEUROTOXICITY
►    PTOSIS
►    OPHTHALMOPLEGIA
►    MYASTHENIA LIKE SYMPTOMS
►    ASSES SBC



HEMATOTOXICITY

►    PURPURA
►    ECHYMOSIS
►    GINGIVAL SULCUS BLEED
►    HEMATURIA

CAPILLARY LEAK SYNDROME
►    PUFFINESS
►    CHEMOSIS
►    PAROTID SWELLING




Lab. Investigations
  
Haematological-
                             leucocytosis(>20,000-
                                     severe envenomation)                          
                            elevated PCV
                             thrombocytopenia
                             evidence of hemolysis
                             prolonged CT,PT,PTT
                             elevated FDP



►    CT     >    20 MINUTES

►    SURE SIGN OF ENVONOMATION

►    PITVIPER   > 2 WEEKS

►    ECG: bradycardia
             ST    /
             Twave inversion
             QT Prolongation
             changes due to hyperkalemia
             

►    Metabolic
         hyperkalemia
         hypoxemia with resp.Ac
         met.Ac or lactic Ac
►    Urine
         hematuria,proteinuria,Hburia
         Mburia
        


►    Renal : ARF -- BU S.Cr   S E
►    CXR :  pulm.edema
               intrapulm.Hgs
               pleural effusion
►     Immunodiagnosis: by ELISA….
     highly sensitive but specificity inadequate to diff b/w diff species of snakes



SPECIFIC MANAGEMENT  ASV
►    HORSE SERUM
►    ASV IN INDIA
                        COBRA
                        KRAIT
                        RUSSEL’S VIPER
                        SAW SCALED VIPER
 1 mi ASV     ---    0.6m6 cobra R viper
                     ---    0.45mg krait S viper
                       


Indication ---- systemic manifestaiton
►    NEUROTOXICITY
►    REPEATED VOMITING
►    HAEMOTOXICITY
►    NEPHROTOXICITY
►    CARDIOTOXICITY
►    RHABDOMYOLYSIS


►    PROLONGED  CT  ALONE

                       PIT VIPER  --  NO
                       SNAKE NOT IDENTIFIED


NEUROTOXIC ENVONOMATION
►    INITIAL DOSE  10  -  15 VIALS
►    REASSESS
►    IMPROVEMENT   30  --  60 MIN
►    REPEAT  5 VIALS AFTER 60  -- 90 MINS
►    SUPPORTIVE – NEOSTIGMINE AFTER ATROPINE


HAEMOTOXIC ENVONOMATION
►    MILD            CT  <  30 MINS
                        CLOT SIZE  =  50% blood col
                        initial dose  = 5 vials
►    MODERATE   CT   >  30 MINS
►                           CLOTS ONLY SPECKLES
►                           intial dose   = 10 vials
►    SEVERE      INCOAGULABLE
►                         initial dose  = 15 vials


►    REPEAT  CT  AFTER 6 – 9 HOURS
►    IF CT PRONGED REPEAT 5- 10  VIALS
►    LOW DOSE INFUSION – FOLLOWING
                                            DAYS


SUPPORTIVE CARE

  ANTIBIOTICS
  METHYL PREDNISOLONE
  FFP,FRESH BLOOD
  PREVENTION AND Rx OF HYPOTENSION
  PRVENTION OF SHOCK



PREVENTION OF ARF
►    PROPER FLUID ADMINISTRATION
►    CORRECT MYOCARDIAL DYSFUNCTION
►    MONITOR OUTPUT BU S.Cr SE
►    AVOID  NEPHROTOXIC DRUGS
►    PROTEIN RESTRICTION



Management of local reactions
►    BULLAE   - LEFT INTACT
►    NECROSIS  - DEBRIDEMENT
►    COMPARTMENT SYNDROME – FASCIOTOMY
►    MOST COMFORTABLE POSITION


REACTIONS TO ANTIVENOM
►    ANAPHYLACTOID  10 – 90 MINS

►    PYROGENIC 2 HOURS

►    SERUM SICKNESS  5 – 21 DAYS
►    Rx  local anaesthetic ice pack


dr.muhammed faisal

calicut medical college