Snake Bite Extraction

[Holy Mackerel]

I was just cruising Midwest's site (www.tongs.com) as I am purchasing some tubing. On the site they have a product called "The Extractor", which is used to extract snake venom (and bee, spider, etc).

Has anyone had any expereince with this product? Does it work at all?

Midwest is a great company with top of the line products (at least hooks and tongs), so if this is a poor product, I am surprised they would be carrying it.


Steve

[BWSmith]

The only real use that I have found for it is to remove tarantula urticating hairs from my skin.

[Removed_2815]

Here's a little debate on the efficacy of venom extractors that I found in the NEW ENGLAND JOURNAL of MEDICINE.

More on Snake-Venom and Insect-Venom Extractors

To the Editor: Dr. Gellert makes several errors of fact and gives a controversial opinion in his letter, "Snake-Venom and Insect-Venom Extractors: An Unproved Therapy" (Oct. 29 issue)1. He is correct in stating that the application of suction to snakebites and hymenoptera stings by most devices is worthless, but he is wrong in his blanket condemnation of all such devices. Bornstein et al.2 have demonstrated that a patented device, the Sawyer extractor, which is capable of producing nearly 1 atmosphere of vacuum, is efficacious in removing up to 37 percent of radiolabeled venom in rabbits when applied three minutes after injection. The use of this extractor as immediate first aid has been advocated by the Wilderness Medical Society in a peer-reviewed position paper,3 in the Merck Manual,4 and in Conn's Current Therapy5.

Contrary to Dr. Gellert's assertion, there is no consensus that it is necessary to kill a biting snake so that it can be identified. In the emergency department, antivenom will be administered on the basis of the extent and rapidity of the swelling of the wound, owing to the frequency of "dry" bites. The exceptions are the bite of the Mojave rattler, which justifies the rapid use of 30 vials of multivalent antivenom (Wyeth), and that of the coral snake, which requires a specific antivenom. Attempting to kill a poisonous snake could place the other members of a party at considerable risk.

It is inconceivable that the Sawyer device could be used incorrectly so that it spread venom further, as Dr. Gellert asserts. Its instructions include the advice not to make incisions into the wound; in fact, Bornstein et al. demonstrate that doing so causes the wound to seal itself under the effect of the strong vacuum and negates the value of using the extractor2.

Gellert is right when he advises persons known to be sensitive to hymenoptera stings to carry kits containing injectable doses of 1:1000 epinephrine, but not when he instructs such persons to inject this agent when bitten, without waiting for symptoms to develop.


William W. Forgey, M.D.
Wilderness Medical Society
Merrillville, IN 46410

References


1. Gellert GA. Snake-venom and insect-venom extractors: an unproved therapy. N Engl J Med 1992;327:1322-1322.[Medline]
2. Bornstein AC, Russell FE, Sullivan JB. Negative pressure suction in field treatment of rattlesnake bite. Vet Hum Toxicol 1985;25:297-297.
3. Iserson KV, ed. Wilderness Medical Society position statements. Indianapolis: Wilderness Medical Society, 1989.
4. The Merck manual of diagnosis and therapy. 15th ed. Rahway, N.J.: Merck, 1987.
5. Rakel RE, ed. Conn's current therapy. Philadelphia: W.B. Saunders, 1988.

--------------------------------------------------------------------------------

Dr. Gellert replies:
To the Editor: Dr. Forgey incorrectly attributes to me a condemnation of all vacuum extractors for the treatment of snake and insect bites. In my letter I merely stated, accurately, that these products have not been evaluated scientifically and found to support the advertising claims of their manufacturers. Extractors thus remain an unproved therapy. Regarding the study cited by Dr. Forgey in which 37 percent of radiolabeled venom in rabbits was removed by an extractor, it is questionable whether a single report of marginal success in an animal model is a suitable basis for widespread marketing of such a product to the public, to whom it is being sold around the globe as a certain therapeutic panacea. The problem remains that these products provide a false sense of security and reduce the imperative to seek professional care, an undesirable consequence even if the product can remove 37 percent of venom in people -- which is unsubstantiated.

The recommendation that a snake of unknown species be killed for the purpose of identification is supported by numerous sources1. There is no question that, as Dr. Forgey points out, attempting to kill a poisonous snake could place people at risk of more bites. Extreme caution is indeed warranted in such a circumstance, but this has not deterred the Centers for Disease Control and Prevention from recommending, in an analogous situation, that a biting carnivore or bat be captured for rabies investigation when a possibly rabid animal has bitten a person in an area not known to be free of rabies2. This recommendation is based on the potentially severe, even fatal consequences of these contacts with animals. Killing animals should not be undertaken lightly, but it should be undertaken.

It is hardly "inconceivable" that an extractor could spread venom if used incorrectly. Devices of much less complexity are frequently used incorrectly by persons with low levels of literacy and education. Dr. Forgey's assertion that people with known hypersensitivity should wait for symptoms to appear after an insect bite before injecting epinephrine is contrary to both the medical literature1 and the manufacturer's recommendations for the use of an epinephrine injector intended for "immediate self-administration by a person with a history of an anaphylactic reaction" (EpiPen)3.

Dr. Forgey has sought to defend the extractor; I have pointed out that its effectiveness in the treatment of snake envenomation remains incompletely documented, and that supportive evidence is entirely lacking for its use in the treatment of insect bites. He has focused on issues such as when epinephrine should be injected by a hypersensitive person with an insect sting -- rather than on the fact that some extractor manufacturers are claiming the device should be used to treat stings, without mentioning epinephrine, a proved therapy. As the Food and Drug Administration moves to hold manufacturers of retail food and medical products to their advertising claims, those made by the manufacturers of extractors should not be exempt, but warrant scrutiny.


George A. Gellert, M.D., M.P.H., M.P.A.
Orange County Health Care Agency
Santa Ana, CA 92701

References


1. Wallace JF. Disorders caused by venoms, bites, and stings. In: Wilson JD, Braunwald E, Isselbacher KJ, et al., eds. Harrison's principles of internal medicine. 12th ed. New York: McGraw-Hill, 1991:2187-94.
2. Rabies prevention -- United States, 1991. MMWR Morb Mortal Wkly Rep 1991;40(RR-3).
3. Physicians' desk reference. 46th ed. Montvale, N.J.: Medical Economics, 1992:843.

[JD@reptiles]

BW, you had another good point when we went herping, the whole mind over matter thing. using it a few inches below the bite so they feel like something is being done, they will calm down and slow the spread of venom.

Dr. Sean Bush did a presentation on snake bite and snake bite treatment at the rattle snake symposium and he said he does not recommend them.

[Removed_2815]

That's a very good point Jordan (or BW), especially when you're talking about something that is so dependent on the person's state of mind. If the person believes it's working, then conceivably they would be less panicked (i.e. lower heart rate).
Interesting...
Ryan

[Holy Mackerel]

Ryan,

I did a little more research and found this in Annals of Emergency Medicine, Volume 43, Issue 2, Pages 181-186
M. Alberts


Suction for venomous snakebite: a study of "mock venom" extraction in a human model.

Alberts MB, Shalit M, LoGalbo F.

Department of Emergency Medicine, University Medical Center, University of California, San Francisco, Fresno 93702, USA. hanamakena@earthlink.net

STUDY OBJECTIVE: We determine the percentage of mock venom recovered by a suction device (Sawyer Extractor pump) in a simulated snakebite in human volunteers. METHODS: A mock venom (1 mL normal saline solution, 5.0 mg albumin, 2.5 mg aggregated albumin) radioactively labeled with 1 mCi of technetium was injected with a curved 16-gauge hypodermic needle 1 cm into the right lateral lower leg of 8 supine male volunteers aged 28 to 51 years. The Sawyer Extractor pump was applied after a 3-minute delay, and the blood removed by suction was collected after an additional 15 minutes. A 1991 Siemens Diacam was used to take measurements of the radioactive counts extracted and those remaining in the leg and body. RESULTS: The "envenomation load," as measured by mean radioactivity in the leg after injection, was 89,895 counts/min. The mean radioactivity found in the blood extracted in the 15 minutes of suction was 38.5 counts/min (95% confidence interval [CI] -33 to 110 counts/min), representing 0.04% of the envenomation load. The postextraction leg count was less than the envenomation load by 1,832 counts/min (95% CI -3,863 to 200 counts/min), representing a 2.0% decrease in the total body venom load. CONCLUSION: The Sawyer Extractor pump removed bloody fluid from our simulated snakebite wounds but removed virtually no mock venom, which suggests that suction is unlikely to be an effective treatment for reducing the total body venom burden after a venomous snakebite.


Interesting.

JD, and BW,

I agree that reducing anxiety is extrememly important, but if you know that this thing doesn't work, i'm not sure how much that will help ;) (but might be a great tactic for those travelling with you that don't know this!!)


Steve

[Removed_2815]

Originally posted by Holy Mackerel
(but might be a great tactic for those travelling with you that don't know this!!)

That's what I'm thinking too. I bet there would be a significant difference in how fast the venom spreads between people who are told that this suction device is guaranteed to remove the venom and people who are told that it's hopeless and they're going to die. I wouldn't call it a placebo effect, but it is quite similar.
Ryan

[Ontario_herper]

Jordan... why did Bush say he wasn't for their use?

[JD@reptiles]

"The Extractor" was tested on a pig with a real rattle snake bite. The suction pulled a little "plug" through the skin and did more damage than good. he said it removed 0.001 of the venom that was injected and said that it should not be used due to the damage.

I just sent Sean an Email asking to send the photograph of the damage the extractor did.

As soon as i get the photo, I will post it.

Jordan

[Reticsrule]

i have "the extractor". i wasnt planning on getting it but i went to a store to buy a flashlight for snake hunting and the guy showed me it and said i "need"one if im looking for snakes. i have never had to use it luckily:)

[SCReptiles]

I am familiar with research claiming the extractor does not remove venom, but to say the extractor never works would be grossly inaccurate. There are certainly occasions when venom would be trapped beneath the skin and would be removed by the negative pressure. The extractor will certainly “hold” venom in place and one must bear that in mind when making the decision to use it. Is the added necrosis worth the possible benefit? In my opinion, location of the bite and venom type are the deciding factors. If I am bitten by a snake known to be neurotoxic, such as a coral snake, I will by all means apply the extractor. If I am bitten by a snake known to be hemotoxic, (Cotton mouth) I will apply the extractor only if the bite location is in such as area that the added necrosis will not out weigh the possible benefit. If bitten in the mass areas of the arm or leg, necrosis can successfully treated in most cases, however, added necrosis in the hand or foot could lead to an amputation. I would not use the extractor below the wriest or ankle, however, I would use it on the arm or leg. I recently took a bite in the forearm from a 40” northern copper. I had the extractor on within a minute and had the compression wrap on immediately following that. This first aide was successful and no anti-venom was needed.

[JD@reptiles]

I got the Email back from Sean but I had no work weather I could use it on the forum. So, when I hear back I will be able to post it.

Jordan

[Holy Mackerel]

Chuck,

Was that the first hit you've taken from a hot?

[SCReptiles]

nope, was number two. first was a timber....couple years before.

[JD@reptiles]

Hey Chuck. How did you manage to get bit on the forearm?

[chas*e]

If your bit reach for a phone before an extractor...and you can play with it while you wait for the ambulance/death

[SCReptiles]

JD: Religious serpent handling.

[BWSmith]

I recently took a bite in the forearm from a 40” northern copper. I had the extractor on within a minute and had the compression wrap on immediately following that. This first aide was successful and no anti-venom was needed.
That logic is a little flawed since you have no idea the degree of envenomation. More than likely, it was a very mild envenomation to begin with. There are far to many variables for such a bold statement to be accurate. If it was mild envenomation, electric shock therapy could have yielded the same result. But I am glad that you recovered so well.

If you think of an envenomation this way, it is easier to understand why the Extractor does not really work. Think of tissue as a wet sponge. Now inject that sponge with red dye (venom). Now try to suck out the red dye. It simply does not work. Same basic premise as when venom is injected into the human body, even a SQ envenomation.

[cobraman]

I have used the Sawyer Extractor on several occasions, but most of my bites have been on areas that were difficult to get good suction, so in most cases it was of no value for me. Even IF it does remove some venom along with other body fluids, it may not remove enough to be of any real value (especially when the venom is one that requires so little to be a real problem).

Just my two cents.
Ray

[fedupdon]

i have used one on the bite of a western massasuga when i went to the doctor there was not a lot of venom in the blood but 2nd infection made treatment cost @2500.00