Tuesday, June 28, 2011

Use an Ointment for Snake Bite?

A nitroglycerine ointment can slow the spread of venom
Time is the foe for people who have been bitten by a poisonous snake, but a new study may give them a bit more of it. Researchers have identified an ointment that slows the spread of some kinds of snake venom through the body, potentially giving snakebite victims longer to reach a hospital or clinic.

Although poisonous snakes kill only a handful of people in the United States each year, the World Health Organization puts the global toll at about 100,000 people. When some snakes strike, the bulky proteins in their venom don't infiltrate the bloodstream immediately but wend through the lymphatic system to the heart. In Australia, a country slithering with noxious snakes, the recommended first aid for a bite includes tightly wrapping the bitten limb to shut the lymphatic vessels—a method called pressure bandage with immobilization (PBI). The idea is to hamper the venom's spread until the victim can receive antivenom medicine, essentially antibodies that lock onto and neutralize the poison. But PBI is not practical if the bite is on the torso or face, and one study found that even people trained to perform the technique do it right only about half the time. As a result, some people don't get antivenom in time.

So physiologist Dirk van Helden of the University of Newcastle in Australia and colleagues went looking for a chemical method to detain the venom. They settled on an ointment that contains glyceryl trinitrate, the compound better known as nitroglycerin that doctors have used to treat everything from tennis elbow to angina. The ointment, prescribed for a painful condition called anal fissures, releases nitric oxide, causing the lymphatic vessels to clench. The researchers first injected volunteers in the foot with a harmless radioactive mixture that, like some snake toxins, moves through the lymphatic vessels. In control subjects that didn't receive the ointment, the mixture took 13 minutes to climb to the top of the leg. But it required 54 minutes if the researchers immediately smeared the ointment around the injection site, the team reports online today in Nature Medicine.
Sounds promising.  Anything to give you more time to get to treatment would be a big help.  It needn't be specific to a particular snake, and I would hope that an ointment could be made that would be stable enough to put in snake bite kites, even if it might have to be in two parts that are mices (stabilized nitroglycerine and ointment separately).  

I keep a calcium gluconate ointment available at home, since we use hydrofluoric acid at work, and the consequences of a HF burn from an unexpected exposure is so severe. 

I wonder if the nitroglycerine ointment would be good for other uses, like dangerous insect stings and spider bites?

No comments:

Post a Comment