( The second article of this two-part series focuses on snake bites, their characteristics and types of toxins, and how they affect your body. Previously, our columnist covered the topic of what to do when a snake bites you (Read that article here.)
You mentioned that the three commonest types of venomous snakes in Malaysia are the cobra, the viper and the sea snake, right? What happens when a cobra bites me? It is the snake I am most frightened of!
Okay, we talked about some local (at the site of the bite) effects once a venomous snake bites you. These include:
• Two puncture marks at the wound from the fangs of the snake.
• Redness and swelling around the bite (denoting inflammation).
• Severe pain at the area of the bite.
• Nausea and vomiting.
• Heavy and difficult breathing. In some cases, you may stop breathing altogether.
• Difficulty in seeing.
• Increased salivation and sweating.
• Numbness or tingling around the face and/or limbs.
These symptoms may vary from person to person, depending on toxin type and amount absorbed.
Cobra bites tend to be very painful and very quick in disseminating toxin, however.
In general, small children are more likely to be affected faster and more severely than adults or teens because of their smaller body size, which allows the toxin to spread faster. Cobras’ toxin contains neurotoxins and cardiotoxins.
What does that mean? Does it mean that a cobra’s bite is doubly dangerous?
A cobra’s bite with envenomation is definitely dangerous. Envenomation means that the venom is injected inside the flesh and bloodstream of the victim.
In addition to all the things that can happen at the site of the bite, as detailed above, the neurotoxins in a cobra’s venom can lead to neurological and neuromuscular symptoms and signs. These are all due to your nerves and muscles being paralysed, including those of your face and brainstem, and ultimately, the nerves and muscles that help you breathe.
Unfortunately, these symptoms will usually present the earliest. It is also important to note that not all symptoms will present.
Your brain can also be severely affected, leading to:
• Drooping of your eyelids (called ptosis).
• Shortness of breath when the muscles of your diaphragm and chest are affected.
• Inability to move your eyes when your eye nerves and muscles are affected.
• Inability to swallow or speak.
• Paralysis of your limbs.
• Inability to lift your head when your neck muscles become paralysed.
• Inability to walk in a straight line. This happens when the part of the brain that controls balance is affected.
• Sudden loss of consciousness.
This sounds awful. That can result in death, right?
If you can’t breathe, ultimately, it will result in death. However, it is the cardiotoxins that are even more dangerous. Cardiotoxins from a cobra’s venom can wreak havoc on your body’s circulation and the heart’s pumping action. They can lead to increased blood pressure.
Your heart can also pump very fast – too fast, in fact. Ultimately, this can result in your whole heart being “overstressed”, and finally not being able to pump. If cardiotoxic complications occur, you can almost be 100% certain that you will die.
Okay, my friend was bitten while we were hiking in the jungle. I have now brought him to the hospital’s A&E department. What will happen to him?
Your friend will immediately be put on a drip (intravenous infusion). Blood will be taken and sent for tests, including blood counts and coagulation profiles.
This is in case the snake was a viper – vipers have haemotoxins in their venom that can cause bleeding and prolonged clotting times. His blood will also be cross-matched just in case he needs blood transfusion. Again, this is because of possible bleeding (internal or otherwise) caused by a viper’s toxin.
They will run a continuous ECG on him to monitor his heart rhythm in case of cardiotoxins from a cobra or snakes that have such in their venom. If no signs and symptoms of envenomation are noted after two hours, then it’s possible the bite was a dry one. Your friend will be observed for 24 hours, then discharged if alright.
If any signs of envenomation occur, then antivenom therapy will be injected. This therapy is the cure. You may need as many as 15 vials for moderate to severe bites.
The rest will be supportive therapy depending on the symptoms.