by Buck Tilton

An estimated 200 species of snakes on planet Earth carry the potential for human death in their venom, and a best guess by experts places the number of deaths each year at more than 50,000. Few of these deaths occur in the United States: None in 1990, one in 1991, one in 1992. Ninety-nine out of every 100 poisonous bites by indigenous snakes in the U.S. are received from a pit viper, family Crotalidae: Rattlesnakes, copperheads, and water moccasins.

All pit vipers have distinctly triangular heads, catlike pupils, heat-sensitive pits between eyes and nostrils, and danger squirting from two very special teeth, hinged to swing downward at a 90-degree angle from the upper jaw. The jaw opens alarmingly wide, allowing the venom to be ejected down canals within the fangs and into the tissue of a prey or enemy. The amount of venom and the toxicity of the venom determine the danger to the bitten. Poison from the Mojave rattlesnake, for instance, rates as approximately 44 times more potent than the Southern Copperhead1s. Arizona is the most likely place to die of a snakebite, with Florida, Georgia, Texas, and Alabama filling out the top five.

Mild pit viper envenomations hurt, swell, turn black and blue, and sometimes form a blister at the site. Moderate envenomations add swelling that moves up the arm or leg toward the heart, numbness, and swollen lymph nodes. A severe envenomation might add big jumps in pulse rates and breathing rates, profound swelling, blurred vision, headache, lightheadedness, sweating, and chills. Death is possible.

How dangerous is pit viper venom to a human? Depends on the age, size, health, and emotional stability of the victims, whether or not they1re allergic to the venom, where they were bitten (near vital organs being the most dangerous), how deep the fangs go, how pissed off or afraid the snake was, the species and size of the snake, and the first aid provided.

Snake venom often varies greatly depending on the species, and specific treatment may vary. Most patients will benefit from these guidelines which have been developed especially for North American pit viper envenomation: Calm and reassure the patient. Keep the patient physically at rest with the bitten extremity immobilized and kept lower than the heart. Remove rings, watches, or anything else that might reduce the circulation if swelling occurs. Wash the wound. Measure the circumference of the extremity at the site of the bite and at a couple of sites between the bite and the heart, and monitor swelling. Evacuate the patient by carrying, or going for help to carry, or, if the patient is stable, by slow walking. Do not cut and suck. Mechanical suction (not oral suction) may be valuable if you get there in the first three to five minutes. Suction should be applied for 30 minutes via the Sawyer Extractor. Do NOT give painkillers unless the patient is very stable, showing no signs of getting worse. Do not apply ice or immerse the wound in cold water. Do NOT apply a tourniquet. Do not give alcohol to drink. Do not electrically shock the patient. Antivenins are available for most pit viper envenomations.

© 1999 Buck Tilton. All Right Reserved.