Snakebite Management Guide for Healthcare Providers in Malaysia 2011

SNAKEBITE MANAGEMENT GUIDE FOR HEALTHCARE PROVIDERS IN MALAYSIA

International Workshop on Advanced Marine animals & Snake Envenomation Management (AMSEM) & Intermediate Level Workshop on Snakebite and Envenomation Management (SEM)

Prepared by Dr Ahmad Khaldun Ismail – December 2011. Updated: June 2013 © Copyrights UKM 2013 Webpage: http://www.facebook.com/amsemukmmc

Date: ___/___/_____ Time: ______hr Name: ___________________ Age: _____y/o

Reg num: ____________

(Note: All cases should be supervised by a physician or clinical toxinologist who are familiar and experienced with snakebite and envenomation management in Malaysia) 1. FIRST-AID TREATMENT Avoid any interference with the bite wound (e.g. tourniquet, incisions, sucking, rubbing, vigorous cleaning, application of herbs/chemicals, massage or electrical shocks). STEP ACTION √ 1 Reassure the victim who may be very anxious. Move away from danger. Reduce physical movements. 2 Lay patient down in a comfortable position, and immobilize the bitten area/limb with a splint or sling. Maintain immobilization throughout the patient’s stay in the ED. 3 Irrigate eyes with copious amount of water if the venom enters the eyes. 4 Remove jewelry and loosen tight-fitting clothing enroute to health centre. Urgent transport. 2. RAPID CLINICAL ASSESSMENT AND RESUSCITATION STEP ACTION 1 Manage patient in Priority I or II area with close monitoring of vital signs and cardiac rhythm 2 Primary clinical assessment (ABCDE approach) and resuscitation as indicated 3 Prop up patient to a comfortable position and administer Oxygen to keep sPO2 >95% 4 Obtain two (2) venous access and maintain with Normal Saline solution 5 Immobilize the bitten limb 3. INVESTIGATIONS 20 minute whole-blood clotting test (20WBCT): It is a quick bed-side test (with a questionable sensitivity) for

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unidentified bite or when a pit viper bite is suspected.

1 2 Note:

Place 2mls of freshly sampled venous blood in a small, new or heat cleaned, dry, glass vessel. Leave undisturbed for 20 minutes at ambient temperature, then tip the vessel once. If initial test was normal (fully clotted) repeat test every 30 minutes for first 3 hours then hourly up to 6hrs post bite or as necessary. If the blood remain liquid (unclotted), this is suggestive of coagulopathy or defibrination syndrome secondary to systemic envenomation from a pit viper bite. Others: Repeat serially. Note: * to include d-dimer and directly measured fibrinogen level. 1 Coagulation profile* 4 Creatine kinase (CPK) 2 Full blood count & picture 5 Urinalysis (myoglobinuria) 3 Renal profile & electrolyte 6 Liver function 4. DETAILED CLINICAL ASSESSMENT A. History: Obtain precise history of the circumstances of the bite. Useful initial questions: STEP QUESTIONS 1 In which part of your body have you been bitten? 2 When were you bitten? What were you doing at that time? 3 Where is the snake or picture of the snake that bit you? Can you describe it? Any eye witness? 4 What did you do after the bite? 5 How are you feeling now? Consider analgesic agent carefully. B. General examination: STEP ACTION (repeat serially) 1 Examine for signs of shock 2 Examine the skin and mucous membranes and in the conjunctivae for evidence of bleeding 3 Thoroughly examine the gingival sulci and the nose for spontaneous systemic bleeding 5 Examine the abdomen for tenderness 6 Examine the Loin (low back) for tenderness 7 Examine for neurological signs

Prepared by Dr Ahmad Khaldun Ismail – December 2011. Updated: June 2013 © Copyrights UKM 2013 Webpage: http://www.facebook.com/amsemukmmc

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C. Examination of the bitten area: STEP ACTION (repeat serially) 1 The extent of swelling (start proximally). Take pictures. Measure distance from bite marks 2 Palpate lymph nodes draining the limb. Note overlying ecchymosis and lymphangitic lines 3 If significant swelling, intra-compartmental pressure should be measured (consider fasciotomy only when >40 mmHg) 4 Blood flow, perfusion and patency of arteries and veins assessed. Capillary refill time < 2secs D. Examination for neurotoxic envenoming: STEP ACTION (repeat serially) 1 Ask patient to look down then look up and observe the upper lids retracting fully or lagging 2 Test eye movements for external ophthalmoplegia 3 Check the size and reaction of the pupils to light (fixed dilated in postsynaptic neurotoxicity) 4 Ask the patient to open his/her mouth wide and protrude his/her tongue (trismus) 5 Check other muscles innervated by the cranial nerves (facial muscles, tongue, gag reflex etc). 6 Examine the neck muscle (the neck flexor muscles may be paralyzed, i.e. “broken neck sign”) 7 Check if patient can swallow or secretions accumulating in the pharynx (early sign of bulbar paralysis) 8 Ask the patient to take deep breaths in and out (look for Paradoxical respiration) 9 Measure the ventilatory capacity. Use a peak flowmeter/spirometer (FEV1 or FVC)

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5. SPECIES IDENTIFICATION (Ref: Image Gallery of Land Snakes of Medical Significance in Malaysia) If the dead snake has been brought or a picture taken, it may be possible to identify it. Take pictures of the dead specimen with a measurement reference (e.g. measuring tape): a. 2 views of the head: top (dorsal) and lateral b. Coil the specimen for 1 dorsal view and 1 ventral view Get an experienced physician or clinical toxinologist familiar with snakes species to verify (e.g. via email or MMS etc.). You may preserve the dead specimen in an airtight container submerged in 10% Formaldehyde (Formalin) or 70% alcohol.

6. ANTIVENOM Antivenom is selected ONLY if its stated range of specificity and para-specific neutralization capacity includes the species known or highly suspected to have been responsible for the bite. Antivenom treatment is recommended when a patient with proven or suspected snake-bite develops one or more of the following signs: Envenomation √ A. Systemic envenoming 1. Haemostatic abnormalities: Spontaneous systemic bleeding, coagulopathy (20WBCT or other laboratory tests) or thrombocytopenia (