Protocol of Snake bite
Viperids (Vasculotoxic)
Russel Viper
Saw Scaled Viper
Elapids (Neurotoxic)
Karait (Bungarus Ceruleus), Cobra (Naja naja).
Dry Bite: In more than 20% of the cases, no venom is released, it causes no harm and no antivenom is required.
Clinical Manifestation of Elapids
General constitutional symptoms are more than the local reactions
Multisystem effects
Cranial, peripheral nerves and respiratory muscles are affected, which are change in taste, mouth numbness, muscle fasciculations, tachycardia/bradycardia.
Pulmonary oedema and renal dysfunctions.
Early findings may consist of ptosis and altered mental status
Cagulophaty, cardiotoxicity, convulsions can occur.
Severe invomation may result in paralysis including muscles of respiration and lead to death from respiratory failure within minutes to hours.
Time of onset of actions of intoxication varies depending on the species involved, site of bite and amount of venom injected.
There may be staggering of gait, in-coordination of speech, paral;ysis of limbs, drooping of head, vomiting, convulsions etc.In krait poisioning, in addition there are convulsiuon and violent abdominal pain due to internal hemorrhage.
Field Management
Clean the bitten part with water without rubbing
Dressing with antiseptic
Immobilizing the bitten part as for fracture.
Entire limb is wrapped immediately with a bandage ( Crepe / Elastic)
Supportive care i.e. A,B,C, airway, breathing and circulation
Bitten part should be positioned at the levcel of heart.
Hospital Management
Closely monitor the vital signs, cardia rhythm, oxygen saturation, urine output etc.
Quickly and rapid thorough physical exams
Large bore I.V. access in one or two unaffected extremities.
Early hypotension is treated with N.S ( 20-40 ml per KG)
If dopamine is required, it should be only be given after aggressive volume resuscitation and anti venom administration.
Antivenom administration
Goal is to allow antibodies to bind up circulating venom before they can attack the target issue.
Antivenom supplied to our hospital is polyvalent
1 ml of syrum neutralizes 0.6 mg of standard cobra venom and 0.45 mg krait venom.
Anti venom indicated at the first sign of any evidence of ptosis or peripheral neuropathy.
It may cause early anaphylaxis and serum sickness.
Some have recommended pretreatment with I.V anti-histamins and adrenalin 0.01 mg per KG up to 3 mg S.C or I.M.
Protocols of manufacture recommends sensitivity test before antivenom administration.
By injecting S.C 0.1 ml of serum in 1:10 dilution and observing for 30 minutes for any local and general reactions.
Adminstration of serum has to be decided taking in to consideration, severity of patient conditions and urgency of treatment must override the danger of anaphylaxis. In such cases it is better to inject 1 ml 1:1000 adrenalin I.M, 0.5 ml may be repeated 15 minutes later, should it be necessary.
As a first dose at least 2 vials of serum should be injected in 250 ml N.S I.V very slowly ( not over 1 ml i.e. 20 drps per minute).
At the first sign of acute reactions i.e. that is a single hive, mild itching, bronchospasm and acute cardiovascular collapses.
In this conditions administration should be stopped temporarily and immediately treated I.M/S.C adrenaline and I.V Avil, dexona or efcorline.
Rate of administration can be increased gradually in the absence of reactions until the fall starting dose has been given for a total period of 1 hour.
Once the reaction is controlled, then the dose should be diluted further in N.S.
Secomd dose should be repeated 2 hours after the first dose or even earlier if symptom persists.
Associated treatmentT.T
Antibiotics if needed ( Usually cephophalosporins)
For pain control only paracetamol .
Other N.S.A.I.D should not be advised because of theireffects on blood clotting.
Stay in the Hospital
Any patient with sign of envenomation should be observed for atleast 24 hours.
Even partient of no sign of envenomation should be observed for at least 8 hour.
Serum sickness
Can menifest as fever, chills, urticaria, myalgia, arthralgia and possibly renal or neurological dysfunctions developing 1-2 week after antivenom adminstartion.
Treatment is oral predenisolone 1-2 mg per KG until the findings resolved, dose is then tappered over 1-2 weeks.
Oral anti-histamins and paracetamol for additional relief of symptoms.
Medical World Dr Rana Sanjay