SNAKE BITES

By BISHAL GYAWALI 



1. Snake venom is a cocktail of proteins: many (>20) are enzymes like phospholipase, ATPase, nucleotidase and other non enzymatic compounds like neurotoxins, hemorrhagins, and cardiotoxins. The outcome of snake bites is very unpredictable ranging from virtually no effect to death.
2. Local pain, paresthesia(altered sensation) and swelling suggest Cobra bites. Tissue necrosis suggests viper bites.

3. Nausea, vomiting, tachycardia, syncope, cold and clammy skin soon after the bite. These features are seen due to fright rxn.

4. Signs of envenomation are : vomiting, shock, bleeding from different sites, neurotoxic effects, reduced level of consciousness. Hemorrhagic effects are more prominent in viper bites; like ecchymosis, bleeding from gums, hemoptysis, hematuria ,malena and DIC. Circulatory collapse and renal failure are most important complications. Neurotoxic effects are more prominent in cobra and krait bites; and include ptosis, ophthalmoplegia, IX and other cranial nerve palsies, slurred speech, dysphagia, respiratory paralysis. Cardiotoxicity in form of arrhythmias, arrest and hypotension can also occur!!

5. What can common people do by themselves in case of snake bite emergency?

a. If they had already killed the snake, preserve it and take that while going to hospital. Identifying the snake helps in better management. But beware, sometimes they maynot have been totally killed!!!

b. Reassure the patient. Give him hope. Encourage him. This point is very important but easily neglected!!

c. Clean the bite site with sterile water and leave the wound open!

d. Immobilize the limb(don’t let him/her walk or move) and apply a firm bandage to occlude lymphatic drainage. This will prevent the venom from getting into circulation!

e. DO NOT----
i. Use a tourniquet
ii. Incise the wound
iii. Attempt to suck out the venom
iv. Use ice to relieve pain.

f. Take to the hospital ASAP.Dont delay !! And keep him/her under doctors observation for 12-24 hrs because the symptoms of envenomation can be delayed(esp with cobra and krait)!!

6. Please give me feedback whether such posts are useful or not. Its not going to come in entrance exams, of course, but i posted it just in case someone requires this knowledge in any emergency they can see here--also as a future medical student sb might have an interest in these things. Do you want such posts related to medicine but useful to common people as well to appear again in this page? Do provide a feedback.

7. Thank you. Lets work together to create a happier and healthier Nepal!!

References: 1. Manual Of Medical Emergencies by Prof. Dr. Gopal P. Acharya
2. Death and Deduction by Prof. Dr. A. J. Chapman
3. Davidson's Principles and Practice of Medicine