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Doc T
02-18-2004, 01:27
You are in north carolina training and your teammate is heard swearing and comes to you with the following saying he has just been bit by something...

most likely culprit?
plan of action?
dangerous?

doc t.

Roguish Lawyer
02-18-2004, 01:33
Originally posted by Doc T
most likely culprit?

My extensive medical training tells me it was a snake. :D

Doc T
02-18-2004, 01:35
did not realize the photo name would show...changed it but too late obviously.... :)

shadowflyer
02-18-2004, 06:43
DX---Snakebite, mostlikely from the viper family due to the distance between the bite marks.


Had to do some research for the following.

NC is home to the following species:

Agkistrodon contortrix-- Copperhead
Agkistrodon piscivorus piscivorus----Eastern Cottonmouth
Crotalus adamanteus----Eastern Diamond-backed Rattlesnake
Crotalus horridus----Timber Rattlesnake
Sistrurus miliarius miliarius----Carolina Pygmy Rattlesnake


If the bite was in fact a rattlesnake, the PT will have the following symptoms:

If a rattlesnake injects venom into the wound, a variety of symptoms develop: swelling, pain, bleeding at the site, nausea, vomiting, sweating, chills, dizziness, weakness, numbness or tingling of the mouth or tongue, and changes in the heart rate and blood pressure. Other symptoms can include excessive salivation, thirst, swollen eyelids, blurred vision, muscle spasms and unconsciousness. Rattlesnake venom also interferes with the ability of the blood to clot properly.

TX ---Rattlesnake bite:


1. Wash area.
2. Cover with pressure bandage.
2.5. Identify snake if possible.
3. Evac for treatment ASAP.
4. Antivenom WILL have to be used to treat the PT, if the bite is found to be from a venomous snake.

Controversy exists in regards to the initial care of a snake bite victim. However, immediate evacuation of the bite victim to the nearest medical facility is the most important method of first aid. Snake classification, if possible, is also helpful. Generally, when care can be administered, it is agreed that splint immobilization and elevation of the bitten part above the level of the heart is indicated. Systemic signs of toxicity should be immediately identified.

Severe symptoms can be life-threatening and must be treated with antivenin, a prescription medication. Antivenin is given intravenously with fluids. Other therapy may include numerous laboratory tests, antibiotics and an update on the tetanus shot, if needed.

Doc T
02-18-2004, 07:32
good research on rattlesnakes so of course I will make it a different type...

lets say he trapped it after it bit him...

shadowflyer
02-18-2004, 07:58
After looking at the picture. It looks to be a Copperhead.

Agkistrodon contortrix-- Copperhead

TX--
Venow is hemotoxic.
Same as for a Rattler but from what I have read there have been no documented deaths from a copperhead bite. The bite will be very painful and cause severe swelling.
The PT will have to be EVAC'd as soon as possible to an appropriate medical facility.

Tissue necrosis and infection seems to be the big factor with a copperhead envenomation.

Guy
02-18-2004, 08:59
1. Keep patient calm.
2. Ice pack to bite area. (Cold reduces blood flow by making capillaries constrict)
3. Ace bandage above bite site to further reduce blood flow.
4. Start IV
5.Evac ASAP!

Generally, when care can be administered, it is agreed that splint immobilization and elevation of the bitten part above the level of the heart is indicated.

Why elevate? Makes no sense...only increases blood flow from the infected area to the heart...GRAVITY.

shadowflyer
02-18-2004, 09:08
Originally posted by Guy
1. Keep patient calm.
2. Ice pack to bite area. (Cold reduces blood flow by making capillaries constrict)
3. Ace bandage above bite site to further reduce blood flow.
4. Start IV
5.Evac ASAP!



Why elevate? Makes no sense...only increases blood flow from the infected area to the heart...GRAVITY.


You are right. I was kinda wondering myself about that, even though I was trusting of the source of the information. I reckon I should go with my first instinct.

Sacamuelas
02-18-2004, 09:25
Memories...
I used to hunt copperheads with my crossman pellet gun by walking the drainage canals in shorts as a kid. They are not that tough. It usually just swelled up and hurt for about a week from what I remember. :p

Great thread Doc T.

My take on the issue after refreshing myself:
-make possible ID of snake by noting pattern/color/shape of head,etc not by trapping it and risking further bite.

-Immobilize bitten extremity, use splinting if available.

-wrap tightly (make sure pulses present distal to your wrap. It is not an arterial tournaquet. It is only to slow lymphatic flow and drainage.

-If possible, try and keep bitten extremity at heart level or in a gravity-neutral position. Raising it above heart level can cause venom to travel into/towards the body. Holding it down, below heart level can cause an increase swelling.

-Go to nearest hospital/evac to medical facility ASAP

Doc T
02-19-2004, 16:32
you are correct... it is a copperhead...sorry it brings back memories for some.

as said before, it is very rarely a fatal injury...just painful. About 8000 snake bites a year of varying types of snakes with about 0.2% being fatal. (Not copperheads but other variety)

as for treatment...most have been mentioned.

Immobilize to lessen the spreading of the venom. After about 20-30 minutes the venom will localize within the wound. So if you can avoid having someone walk who has just been bitten it is advised to wait the 30 minutes....obviously depends on the situation.

remove all bracelets, rings, watches, etc that can become constricting as the extremity swells because it will swell...that includes boots.

as mentioned wrap tightly but not too tightly. You don't want to cut off arterial flow. The wrap needs to be reassessed frequently because it can start off loose enough but quickly become tight with the increased swelling on will expect.

Pain control would be nice...

no cutting or sucking of venom...doesn't work and cutting may actually increase the spread of the venom.

Icing is questionable as recent studies show it may make the wounds worse and not help to decrease the spread.

just a side note...when do you consider antivenom? I know you would not carry it in the field...just asking.

doc t.

Razor
03-04-2004, 09:43
Guy, is the IV to possibly dilute the venom in the bloodstream?

Guy
03-04-2004, 10:02
Originally posted by Razor
Guy, is the IV to possibly dilute the venom in the bloodstream?

No...It's for the introduction/administration of drugs if need be.

Doc T:



remove all bracelets, rings, watches, etc that can become constricting as the extremity swells because it will swell...that includes boots.

As much as I love my wife...the wedding band comes off when I'm working. The only thing I wear is a G-Shock watch.

If the individual is ambulatory...his boots stay on! He may just have to walk some until we can get him evacuated.

myclearcreek
04-14-2004, 15:02
Great thread.

One more question. In the case of the patient having asthma, is anything going to change regarding treatment? I would obviously have an inhaler handy wherever we go, but the nebulizer stays in the house near an electric socket.

Surgicalcric
04-14-2004, 15:15
Not unless he begins having respiratory difficulty.

At that point your treatment would be aimed at the cause. You can try the inhaler, but the cause of respiratory difficulty would be the toxin itself. The patient would require other medications (Epi and Brethine here in the civilian world) and possibly an advanced airway.

myclearcreek
04-14-2004, 15:18
Originally posted by Surgicalcric
Not unless he begins having respiratory difficuly. At that point your treatment would be aimed at the cause.

Epi and Brethine here in the civilian world.


That is what concerns me. I have this fear he will have a severe attack if he gets hurt badly. Asking for the epi seems to be an even better idea now. Thanks.

Surgicalcric
04-14-2004, 15:21
If you ask, make sure you get atleast two.

myclearcreek
04-14-2004, 15:37
Originally posted by Surgicalcric
If you ask, make sure you get atleast two.

Thanks. I'll call and ask and get the specifics.

Team4medic
04-22-2004, 01:58
For whst it's worth, I have yet to give antivenin for Copperhead bites. They usually cause a lot of swellin and pain but no significant systemic findings. I would temper my last statement if the victim was very young or old. Fortunately, I've had no major problems with Copperhead bites. Only local care would be indiated

Rattle Snakes, Cotton Mouths are anther story. They do cause Severe pain and swelling sometimes needing an escharotmy.Systemic tocxicity is common and antivenin is usually needed

I'd worry more about this bite!!!

Doc T
04-22-2004, 02:57
usually not an escharotomy but rather a fasciotomy, no?

Doc T
04-22-2004, 03:12
Originally posted by Team4medic


Rattle Snakes, Cotton Mouths are anther story. They do cause Severe pain and swelling sometimes needing an escharotmy.Systemic tocxicity is common and antivenin is usually needed





There are specific indications for the use of antivenom because of the risk ofa hypersensitivity reaction or anaphylaxis. Therefore, antivenom is indicated only if serious manifestations of envenomation are evident (coma, neurotoxicity, hypotension, shock, bleeding, DIC, acute renal failure, rhabdomyolysis and ECG changes for example). In the absence of the above, extensive swelling or increasing bruising or edema within a very short time (30-60 minutes) can also be an indication.

This is all taken off a site here online that I thought gave useful information


Dose


Despite widespread use of antivenom, there are virtually no clinical trials to determine the ideal dose. Conventionally 50 ml (5 vials) is infused for mild manifestations like local swelling with or without lymphadenopathy, purpura or echymosis. Moderate envenomation defined by presence of coagulation defects or bradycardia or mild systemic manifestations, merits the use of 100 ml (10 vials). 150 ml (15 vials) is infused in severe cases, which includes rapid progression of systemic features, DIC, encephalopathy and paralysis.



Administration


The freeze dried powder is reconstituted with 10 ml of injection water or saline or dextrose . A test dose is administered on one forearm with 0.02 ml of 1:10 solution intradermally. Similar volume of saline in the other forearm serves as control. Appearance of erythema or wheal greater than 10 mm within 30 min is taken as a positive test. In this event, desensitization is advised starting with 0.01 ml of 1:100 solution and increasing concentration gradually at intervals of 15 minutes till 1.0 ml s.c can be given by 2 hours. Infusion is started at 20 ml/kg per hour initially and slowed down later.


Antivenom is administered by the intravenous route and never into fingers or toes. Some authors recommend that 1/3 to 1/2 the dose be given at the local site to neutralize venom there. However, animal experiments have established that absorption begins almost instantly from bite sites. Besides this, systemic administration of antivenom has been shown to be effective at the local site as well. Therefore most experts do not advise local injection of antivenin.

Efficacy of intramuscular administration of antivenom followed by standard hospital management has also been evaluated and a definite reduction in the number of patients with systemic envenomation, complications and mortality from Russell's viper toxemia has been noted. This route of administration is likely to have value in a field setting prior to transfer to better facilities.


Timing


There is no consensus as to the outer limit of time of administration of antivenom. Best effects are observed within four hours of bite. It has been noted to be effective in symptomatic patients even when administered up to 48 hours after bite. Reports suggest that antivenom is efficacious even 6-7 days after the bite. In experimental settings, rats injected with antivenom even 3 weeks after the bite showed good response. It is obvious that when indicated, antivenom must be administered as early as possible and data showing efficacy with delayed administration is based on use in settings where patients present late.


Response


Response to infusion of antivenom is often dramatic with comatose patients sitting up and talking coherently within minutes of administration. Normalization of blood pressure is another early response. Within 15 to 30 minutes, bleeding stops though coagulation disturbances may take up to 6 hours to normalize. Neurotoxicity improves from the first 30 minutes but may require 24 to 48 hours for full recovery

If response to antivenom is not satisfactory use of additional doses is advocated. However, no studies establishing an upper limit are available and infusion may be discontinued when satisfactory clinical improvement occurs even if recommended dose has not been completed. In experimental settings, normalization of clotting time has been taken as end-point for therapy.


Reactions


Hypersensitivity reactions including the full range of anaphylactic reactions may occur in 3-4% of cases, usually within 10 to 180 minutes after starting infusion. These usually respond to conventional management including adrenaline, anti-histamines and corticosteroids.