This week, Patrick Snowman, a board-certified emergency medicine physician at Hilton Head Hospital, discusses the treatment of snake bites.
Question. If someone gets bitten by a poisonous snake, is it a good idea to suck the venom out? What's the best way to treat snake bites, and how common are they in this area?
Answer. As the weather warms up, the potential for coming across snakes around your home and community greatly increases. These cold-blooded creatures spend more time out in the open in the warmer months of the year. In the U.S. alone there are 8,000 venomous snake bites yearly, with most of them between April and October. It's extremely important to know how to prevent snake bites: Avoid the animal altogether.
The most common kind of snake in the Hilton Head area is the pit viper, which includes the copperhead, cottonmouth and water moccasins. They get their name from heat-sensing pits in the middle of their eyes on their triangular heads. Of those snakes, you will most likely run across copperheads. They are nocturnal animals and ambush hunters. They stay in the shade during the day and come out in the evening to cool off and feed. Copperheads don't pursue prey; they lay and wait for it. They are not normally aggressive toward humans, and camouflage is their main form of defense.
You are most likely to encounter copperheads in places like your driveway, yard, on the golf course and around a pool deck. The vast majority of bites occur because the snakes aren't seen and are stepped on. If you go outside at night, from dusk on, you need a lighting source because you need to be able to see where you are stepping. Avoid pine straw and dense, grassy areas, and don't step where you can't see.
Some snake bites are either nonvenomous warning bites or "dry" bites. Adult snakes are able to control how much venom they release in a warning bite, whereas a juvenile snake might not have the skill of a warning bite and will release their full venom load. If you get bit by a snake, the most important thing to notice is pain. If they inject venom during the bite, it will be intensely painful -- if not immediately, within an hour.
An envenomation from a pit viper often results in swelling, bruising and blisters in the affected extremity. This swelling and bruising can progress rapidly. Less commonly, there may be systemic symptoms such as hypotension, numbness and tingling, nose bleeds and respiratory distress. Symptoms are also more severe in children.
Many techniques for removal of the venom are no longer used, such as sucking out the wound, cutting an "X" into the puncture wound or heat or ice packs. It is suggested to minimize activity, lay still, and seek medical attention as soon as possible.
Antivenin is the treatment of choice in significant envenomation of poisonous snakes. CroFab (crotalidae polyvalent immune antibody) has replaced horse antivenin because of its effectiveness, and it has a lower risk for immediate allergic reactions and serum sickness. Antivenin binds to the toxins in the venom to prevent local and systemic effects. Best results are achieved if given in the first four to six hours of an envenomation.