Snake bite and Management by Dr Sowmya.pptx
- 1. Case presentation Snake bite poisoning and management Chair person – Dr. M Kiran Sir ( Prof) Co chair person – Dr. Padmavathi Mam ( Asso prof) Moderator – Dr. Alekhya Mam ( Asst prof) Presenter – Dr. Sowmya ( pg 2nd yr)
- 2. Chief complaints A 59 year old male patient named Sathayya, farmer by occupation , resident of Sangareddy presented to the emergency department on 29/9/24 at 3.30pm with swelling , redness of right lower limb and difficulty in breathing with alleged history of snake bite on right lower limb PRESENTING ILLNESS • Alleged history of snake bite on right lower limb on 29/9/24 around 1pm • Pain, burning sensation of rt LL at the bite area • Swelling of right lower limb till knee joint • Drooping of eyelids, blurring of image, doubling of images • Shortness of breath
- 3. • Slurring of speech • Decreased swallowing ( drooling of Saliva ) • No bleeding from the site of bite • No bleeding gums / epistaxsis / Conjuctival hemorrhage / dark colored urine • No blood in sputum / vomitus • No rashes • No muscle pain • No involuntary movements • Generalized weakness present
- 4. • History of past illness: No similar complaints in past. Not a known case of hypertensive, diabetes mellitus, bronchial asthma, TB, epilepsy, CVA, CAD. • Family history: not significant • Personal history: Mixed diet Appetite – normal Sleep – adequate Bladder and bowel movements – normal • Addictions – occasional toddy drinker and beedi smoker since 25 years • No significant history of allergies • No Previous history of surgeries or blood transfusions.
- 5. ON EXAMINATION Patient is conscious, irritable, slurring of speech • two puncture marks on right lower limb • Swelling, redness and pain around the bite area • Drooping of eyelids present • No pallor, icterus, cyanosis, clubbing, lymphadenopathy Edema of right lower limb till knee • Hr – 130/min, Bp – 160/90 mmHg in supine position in left upper limb • CVS – s1 s2 heard
- 6. • Spo2- 96% on 10lit oxygen • Rs – bilateral air entry + , clear • Single breath count – 15 • Breath holding test – 17 sec • Unable to complete one sentence in single breath • Cannot lift his neck completely.
- 7. SYSTEMATIC EXAMINATION Respiratory system • Inspection – chest : bilaterally symmetrical Trachea- midline Respiratory rate – 25 / min Equal rise in hemithorax • Palpation – all inspectory findings confirmed • Percussion – reasonant sounds heard in all lobes bilaterally • Ascultation – bilateral air entry present , clear
- 8. • Cardiovascular examination: s1,s2 heard no murmurs heard • Abdominal examination: Soft, no organomegaly bowel sounds present. • Neurological examination: Pupils- b/ l 4 mm , reacting to light Motor power- 2/5 in lower limbs, 3/5 in upper limbs
- 9. At EMERGENCY DEPARTMENT • High flow nasal oxygen support of 10 lit / min was kept • 20 G IVC was secured on left upper limb • 20 min whole blood clot test was done – no clot was formed ( +) • Anti snake venom 10 vials bolus was given over 30 min • Tourniquet tied to lower limb was released AFTER 30 MINS OF ARRIVAL - RR-45/min , spo2- 80 % on 15 lit O2 • Patient was kept in supine position. After thorough suction patient was pre- oxygenated with 100% oxygen for 3 mins - Inj. Midazolam 10 mcg/ kg , Inj. Fentanyl 1mcg/ kg IV were given
- 10. • Patient was induced with Inj. Propofol 1mg / kg and intubated with 8 mm endotracheal tube. Foleys catheterization was done to monitor urine output • Inj. Paracetamol 1gm IV given for pain management of bite • Inj. TT was given. • Baseline Investigations – CBP,LFT, RFT, SERUM ELECTROLYTES , PT INR , aPTT were sent • CHEST XRAY PA VIEW , ECG taken • Abg was sent. • Grbs -125 mg / dl Patient shifted to AMC with bains circuit for further management
- 11. In AMC • PT was connected to Mechanical ventilator • Ventilator settings – V-SIMV mode FiO2- 70% , RR – 14/ min Tidal volume – 400 ml, PEEP - 5 • Monitors – NIBP , pulse oximeter, ECG were connected and monitored • 20 min WBCT was repeated after 1 hr after 1st dose of ASV – no clotting of blood • ASV 10 vials in 100 ml NS was repeated
- 12. • AN test was done- Inj Atropine 0.6 mg + Inj Neostigmine 1.5mg IV were given. 2 doses were repeated in 30 mins. • Patient is able open eyes ( dropping was decreased ) • Prophylactic antibiotics were given to prevent further infection at bite site. • IV fluids @ 100 ml / hr was given • 20 WBCT was repeated after 1 hr and the blood was clotted.
- 13. • Patient is conscious, irritable • Able to open eyes. Drooping of eyelids decreased • Gcs- E3 Vt M 3 • BP- 130/90 mm hg • Pr- 105/ min • Spo2 – 97% on MV fio2 40% • CVS – S1 S2+ • Rs- bilateral air entry+ clear • Urine output – 50 ml / hr • Grbs – 110 mg/dl INVESTIGATIONS •Hb- 10 mg/dl •WBC- 15k /micro litre •Platelets – 1.01 lakh / micro litre •Blood urea- 64 mg / dl •S. Creatinine – 1.4 •PT – 14 sec •INR- 1.1, aPTT – 37 sec •Na+ 139, K+ 4.9, Cl- 105 •LFT- with in normal limits DAY 1
- 14. DAY 2 • PT was self extubated • ABG – pH – 7.354 paCO2 – 34 mmhg paO2-140 mmHg HCO3- 17 • GCS – E4V5M6 • All other investigations are normal • Local necrosis in the bite area was present. Referred to surgery department for further management
- 15. Provisional diagnosis • A 59 yr old male patient named Sathayya , farmer by occupation presented with alleged history of snake bite with symptoms of swelling , redness, pain of lower limb, drooping of eyelids, difficulty in breathing most probably diagnosed as Neurotoxic snake bite poisoning.
- 17. CLASSIFICATION Broadly classified into 2 types 1. POISONOUS 2. NON POISONOUS POISONOUS snakes are classified into 3 types based on the venom ( toxin) secreted 1. Elapidae (Neurotoxic) – Cobras, krait 2. Viperidae (Haemotoxic) – Russels viper, pit viper 3. Hydrophidae (Myotoxic) – Sea snake
- 19. INTRODUCTION • Snakebite is an acute life threatening time limiting medical emergency. • Only 22.19% of the snakebite victims attended the hospitals. Nearly 65.7% of the snakebite deaths were due to common krait bite • Out of total number of bites only 30% are venomous bites. • Delayed administration of ASV or waiting until victim develops systemic manifestations results in systemic envenoming and high fatality
- 20. WHO Stages of management • First aid treatment • Transport to hospital • Rapid clinical assessment and resuscitation • Investigations/laboratory tests • Antivenom treatment • Observing the response to antivenom • Supportive treatment • Treatment of the bitten part • Follow-up and rehabilitation
- 21. FIRST AID TREATMENT 1. Check history of snakebite and look for obvious evidence of a bite (fang puncture marks, bleeding, swelling of the bitten part etc.) 2. Reassure the patient 3. Immobilize the limb in the same way as a fractured limb 4. Nil by mouth till victim reaches a hospital 5. Remove shoes, rings and tight clothing from the bitten area as they can act as a tourniquet when swelling occurs. 6. Clean superficially with plain water
- 22. Immobilisation of the limb Non poisonous and POISONOUS bite KRAIT bite have no bite marks. Visible only with magnifying lens
- 23. Don’ts 1. Do not wash wound (rubbing, vigorous cleaning, application of herbs or chemicals, cryotherapy, cautery) may introduce infection, increase absorption of the venom and increase local bleeding 2. Do not apply or inject antisnake venom (ASV) locally. 3. Do not tie tourniquets as it may cause gangrenous limbs. (crepe bandage can be used) 4. Do not cut or suction the bite ( the large number of viper bites – have anti-haemostatic effect of the venom, increases the risk of severe bleeding)
- 24. TRANSFER TO HOSPITAL • Avoid movement of the bitten limb( muscle contraction ) as it increase the systemic absorption of venom. • Patients should be placed in the left lateral position. • During transfer, continue life-supporting measures, insert nasogastric tube and provide airway support ( oxygen supplementation) if required.
- 26. ASYMPTOTIC • Nonspecific symptoms related to anxiety. • Palpitations, sweating, tremulousness, tachycardia, tachypnoea, elevated blood pressure, cold extremities and paraesthesia, dilated pupils suggestive of sympathetic over activity. • Redness, increased temperature, bleeding and tenderness locally. Local swelling can be present due to tight ligature i.e., non Venom related symptoms DRY BITE:Not always accompanied by the injection of venom . Symptoms associated with panic or stress.
- 28. 1.NEUROPARALYTI C • Symptoms within 30 min– 6 hours in case of Cobra bite and 6 – 24 hours for Krait bite • These symptoms can be remembered as 5 Ds and 2 Ps. • 5 Ds – dyspnea, dysphonia, dysarthria, diplopia, dysphagia • 2 Ps – ptosis, paralysis • All these symptoms are related to 3rd , 4th , 6th and lower cranial nerve paralysis. Finally, paralysis of intercostal and skeletal muscles occurs in descending manner. Single breath count, breath holding test – done
- 29. 2. VASCULOTOXIC ( HAEMOTOXIC / BLEEDING) Local manifestations: • Local swelling, bleeding, blistering, and necrosis. • Pain at bite site and severe swelling leading to compartment syndrome. Systematic manifestations: • Visible systemic bleeding eg.gingival bleeding, epistaxis, ecchymotic patches, vomiting, hematemesis, hemoptysis, bleeding per rectum, subconjunctival hemorrhages, continuous bleeding from the bite site. • Petechiae, purpura ecchymoses, blebs and gangrene.
- 30. • Acute abdominal tenderness may suggest gastro-intestinal or retro peritoneal bleeding. • Asymmetrical pupils may be indicative of intracranial bleeding Life threatening complications : • Renal involvement. • Patient presents with hematuria, hemoglobinuria, myoglobinuria followed by oliguria and anuria with acute kidney injury (AKI). • Reddish or dark brown urine or declining urine output • Hypotension due to hypovolaemia or direct vasodilation aggravates acute kidney injury.
- 31. 3. PAINFUL PROGRESSIVE SWELLING (PPS) • Indicative of local venom toxicity. Prominent in Russel’s viper bite, Saw scaled viper bite and Cobra bite. • Local necrosis. • Limb is swollen , taut and shiny • Blistering • Ecchymoses due to destruction of blood vessel wall.
- 32. 4. MYOTOXIC • Common in Sea snakebite. • Patient presents with: • Muscle aches, muscle swelling, involuntary contractions • Passage of dark brown urine. • Compartment syndrome, cardiac arrhythmias due to hyperkalaemia, acute kidney injury due to myoglobinuria, and subtle neuroparalytic signs.
- 33. RESUSCITATION CRITICAL ARRIVAL : FIRST HOUR is the Golden hour in Snakebite management CABD approach • CIRCULATION (arterial pulse)– hypovolemia corrected with crystalloids, colloids, inotropes • AIRWAY – o2 support, mechanical ventilation if needed • BREATHING - respiratory movements, single breath count , breath holding test • DISABILITY of the nervous system (level of consciousness, tone of muscle)
- 34. Profound hypotension and shock - such as hypovolaemia, haemorrhagic shock or rarely primary anaphylaxis induced by the venom itself. Terminal respiratory failure – mechanical ventilation. Sudden deterioration or rapid development of severe systemic envenoming following the release of a tight tourniquet or compression bandage Before removal of the tourniquet, test for the presence of a pulse distal to the tourniquet. If patient arrives late – renal failure, Septicaemia, complicating local necrosis. Cardiac arrest – due to hyperkalemia
- 35. DIAGNOSIS 20 Minute Whole Blood Clotting Test (20WBCT) -A few ml of fresh venous blood is placed in a NEW, CLEAN AND DRY GLASS vessel/tube and left at ambient temperature for 20 min Left undisturbed for 20 minutes and then gently tilted, not shaken. - If blood clotted – No need ASV - If blood is not clotted – Start ASV • The patient is re-tested every hour for the first three hours and then 6 hourly until test result is clotted.
- 36. ANTI SNAKE VENOM • Indicated when signs and symptoms of envenomation are present • Anti snake venom (ASV) in India is polyvalent i.e. It is effective against all the four common species;
- 37. ASV DOSAGE • Only by the IV route, given slowly • The rate of infusion can be increased gradually (over a period of ~1 hour). • NEVER be given by the IM route because of poor bioavailability • NOT inject the ASV locally at the bite – ineffective, painful, produce compartment syndrome. • If the biting snake is identified to be a Saw Scaled Viper, 5 vials may be given as a starting dose. Otherwise in all cases, starting dose remains 10 vials.
- 38. • For neuroparalytic snakebite – ASV 10 vials stat over 30 minutes followed by 2nd dose of 10 vials after 1 hour if no improvement within 1st hour. • For vasculotoxic snakebite – Two regimens low dose infusion therapy and high dose intermittent bolus therapy can be used Low dose infusion therapy – 10 vials stat dose over 30 mins f/b 2 vials every 6th hrly in 100ml NS ( clotting time normalizes / 3 days) High dose intermittent bolus – 10 vials over 30 mins f/b 6 vials 6th hrly till clotting time normalizes or local swelling subsides. • In case of life saving surgeries planned immediately after snake bite – High doses upto 30 vials of ASV are used. • Doses for pregnancy and pediatric patient remain same as adults dose
- 39. ASV can • Bind to a venom molecule that it is free in blood and prevent from binding to target cell. • Prevent patient condition from worsening by neutralizing free venom. ASV cannot • Reverse local swelling / necrosis of tissue • Reverse renal failure • Reverse coagulopathy • Reverse nerve damage
- 40. ADVERSE ANTI SNAKE VENOM REACTIONS • Early anaphylactic reaction: occurs within 10mins - 3hrs Itching, utricaria, dry cough, nausea, vomiting, diarrhoea, abd colic, tachycardia, fever. • Pyrogenic reaction: after 1-2 hrs. Chills, rigors, fever, hypotension • Late reaction ( serum sickness) : 1-2 days Recurrent utricaria, myalgia, arthalgia, lymphadenopathy, nephritis, encephalopathy Occurs due to complement activation by ASV proteins or immune complexes
- 41. Treatment of adverse reactions • Stop ASV • Give epinephrine ( 1: 1000 ) 0.5 mg i.e 0.5 ml in adults IM Children 0.01 mg / kg • Chlorpheniramine maleate 10 mg in adults , children 0.2mg/ kg IV • Adjust the speed of ASV and start slowly after the reactions subside
- 42. INVESTIGATIONS • Heamogram - anemia ( hemolysis) , neutrophilic leucocytosis ( systematic absorption of venom) • Renal function tests – serum creatinine elevated in AKI • Coagulation profile – PT , aPTT elevated • Urine examination – Proteinuria, Hemoglobinuria • ECG – Non specific changes : Bradycardia, AV blocks with ST changes • Serum electrolytes – hyperkalemia • ABG – respiratory or metabolic acidosis
- 43. NEUROTOXIC ENVENOMATION 1. AN CHALLENGE TEST • Anti Snake venom treatment alone is not enough • Neostigmine is an anticholinesterase that increases Ach at NMJ and can reverse respiratory failure and Neurotoxic symptoms • DOSE - Atropine 0.6mg + Neostigmine 1.5 mg IV stat Repeat dose atropine + neostigmine 0.5 mg every 30 mins for 5 doses Children Atropine 50 mcg/kg + neostigmine 40mcg/kg Repeat dose neostigmine 10mcg/kg (30min - 5 doses).
- 44. • 50% or more recovery of ptosis in 1 hr – positive AN challenge test • Stop Atropine neostigmine if - Completely recovered from neuroparalysis - Fasciculations or Bradycardia - No improvement after 3 doses Improvement by atropine neostigmine indicates Cobra bite. • If no improvement indicates Krait bite – Krait affects pre- synaptic fibres where calcium ion acts as neurotransmitter. • Give Inj. Calcium gluconate 10ml IV (in children 1ml/kg slowly over 5-10 min) every 6 hourly
- 45. 2. SUPPORTIVE TREATMENT: AIRWAY support – • Loss of gag reflex, cough reflex, pooling of secretions, respiratory distress, a cuffed endotracheal tube or LMA ( laryngeal mask airway) should be inserted. • Suction should be kept ready – secretions / blood / food particles can be present • Nasal airways and oral airways are kept ready – tongue fall is common. • Avoid sedatives & neuromuscular blocking agents Bridging devices – Laryngeal tubes, combitube, Laryngeal mask airways are used as bridging devices till definitive airway ( endo tracheal tube ) is secured.
- 46. • In the ICU, assisted ventilation provided and monitored for level of consciousness. • Some patients go into a deep coma state but recover completely. Diagnosis of brain death should not be considered. • Recovery of respiratory muscles is reflected by improvement of neck flexors indicates timing to wean off ventilation. • Advanced investigations including bacterial cultures and imaging (CT scans) • CNS complication and intracranial bleeding , Neurosurgical opinion considered • Patient in deep coma recovers fully provided there is no hypoxic brain damage. • Uncommon complications such as hepatic dysfunction, pancreatitis, endocrine insufficiency and deep venous thrombosis should be managed
- 47. HEMOTOXIC ENVENOMATION • Hypotension is most common due to hemorrhage, vasodilation effects of venom. - 2 litres of isotonic saline given until JVP is raised 8-10 cm above the sternal angle - Inj. Dopamine 2.5 mcg/kg/min given ( In cases of increased capillary permeability) - plasma expanders - raise the foot end of patient • Persistent or severe bleeding - in majority of cases ASV stops bleeding. - transfusion of FFP’s , cryo, platelets
- 48. • Renal failure - occurs due to intravascular hemolysis , DIC, nephrotoxicity , hypotension, rhabdomyolysis. INDICATIONS for dialysis - Urine output < 400ml/ day or < 20 ml / hr - Blood urea > 130mg/ dl - serum creatinine > 4 mg /dl - serum potassium >7 mmol/l - fluid overload - unresponsive to conservative treatment
- 49. PAIN & WOUND MANAGEMENT • Snake bite is very painful ! - Due to tissue damaging toxins • Paracetamol 500 – 1000 mg ( adults) , 10 mg/kg ( children) 4-6th hrly orally. • Tramadol 50 mg oral can be given in severe pain. • Aspirin , NSAIDS are contraindicated due to impaired hemostasis. • Prophylactic Broad spectrum antibiotics are given for cellulitis after completion of 1st 10 ASV vials. • Tetanus toxid (TT) Injections are given
- 50. SURGERY & SNAKE BITE • Debridement of necrotic tissue - Local necrosis occurs due to venom action - Wait for 5-7 days before debridement to get a line of demarcation between viable and non viable tissue • Compartment syndrome - immobile, tensely-swollen, cold and apparently pulseless snake-bitten limb - increase in tissue pressure above the venous pressure, resulting in ischaemia - clinical features: 6 P’s – pain on passive stretch, pain out of proportion Pulselessness, pallor Paresthesia, Paralysis
- 51. - Intra compartmental pressure > 40mmhg (adults) - Clinical features of compartmental syndrome - After correcting hemostatic abnormalities Early treatment with ASV remains the best way of preventing irreversible muscle damage WHO criteria for fasciotomy
- 52. SNAKE VENOM OPTHALMIA • Sometimes snake spat venom into eyes of the person - extreme pain & conjunctivitis . MANAGEMENT • Decontamination with copious irrigation with water • Instill topical 0.5% adrenaline into eye • Topical local anaesthetics – tetracaine, proparacaine • Topical antibiotics – moxifloxacin • Topical cycloplegics – prevent posterior synechiae, Ciliary spasm • Antihistaminics – in allergic kerato-conjunctivitis
- 53. FOLLOW UP • Advised to return to emergency in case of – increased bleeding, worsening of pain & swelling at the site of bite, difficulty in breathing and altered sensorium • The patients should also be explained about the signs and symptoms of serum sickness. (fever, joint pain, joint swelling) which may manifest after 5-10 days. REHABILITATIO N • Severe local envenoming, the limb should be maintained in a functional position.( Persistent stiffness) • In case of tissue loss, especially dermonecrosis, and requiring skin grafting and gangrene requiring debridement and amputation. • Simple exercises, rehabilitation activities are advised at the time of discharge. • Conventional physiotherapy can accelerate functional recovery of
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