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A Definitive Study of Snakebite
Wilderness and Environmental Medicine, 12, 276-279 (2001)
LESSONS FROM HISTORY
A Definitive Study of Snakebite' C. C. SNYDER, M.D., J. E. PICKINS, M.D., R. P. KNOWLES, D.V.M., J. L. EMERSON, and W. A. HINES of injection and the variable of the victim's blood volume. The lethal doses of various snake venoms are dependent upon the pharmacologic complexity of the venom and the venom action in the tissues that are attacked. Injections of venom deep into the large muscle mass in the lower extremity is more detrimental than antigen injected into the forehead or scalp because action of the moving leg muscles spreads the poison, therefore creating difficulty in retrieving it. Also, in comparison, the scalp muscles tend to move less and the skull bone does not permit deep penetration, thus providing for easier removal of the antigen. Children, with a comparatively small blood volume, experience severe envenomation reaction because of venom concentration; the larger blood volume of an adult provides more diluent for the toxin, consequently rendering it less potent. The ratio of venom injected to victim's blood volume is the reason children necessitate more vigorous therapy to combat the effects of snakebite. Mindful of these variables, we outlined an investigation a decade ago to study the effects of snake venoms, to evaluate conventional treatments as well as other methods of therapy and to ascertain which treatments contribute to the best results. The four types of poisonous snakes in the United States are the rattlesnake, moccasin, copperhead and coral snake. The experiment was devoted to the venoms of the cottonmouth water moccasin (Ancistrodon piscivorus) and the eastern diamondback rattlesnake (Crotalus adamanteus). The poisons were introduced by natural bites of the snakes as well as purified venom injections labeled with Iodine 131 . Control subjects were included in the 139 canines which constituted the nucleus of the experimental effort. Many of these animals were later given away as pets. There were 41 human subjects of whom Dr. Snyder is formerly clinical associate professor of plastic surgery, 19 were bitten by the eastern diamondback rattlesnake, University of Miami School of Medicine. 10 were victims of pygmy or ground rattlesnakes and 12 From the Departments of Surgery, University of Utah College of Medreceived cottonmouth moccasin bites. Therapeutic meaicine and Veterans Administration Hospital, Salt Lake City, Utah. sures evaluated included use of the tourniquet, cryo1 Excerpt reprinted with permission from the J Fla Med Assoc, Vol therapy, cruciate incisions, linear incisions, excisions, 55, No 4, April 1968, pp 330-337. Original style, spelling, and puncsuction, alcohol ingestion, rest and activity. tuation have been retained. Several figures have not been used, owing All of the animal subjects which were injected with to the difficulty of reproducing them. Figures 5 and 9 have been rethe isotope-tagged venom were given lethal doses preproduced as Table 1 and Figure 1, respectively.
Many therapeutic traditions for poisonous snakebite terminate short of expectation. The mortality rate is not disastrously high, but the morbidity is frequently prolonged with the resultant physical disability and financial loss. More published reports exist concerning serpentine envenomation than most readers have time to peruse. Unfortunately, many of these offer personal opinions in good faith which actually are of little value and occasionally are harmful. These clinical reports of snakebite patients confuse the inexperienced therapist and may lead to dreadful sequelae. Therapeutic rationale of envenomation will never be determined by treating an occasional victim with a presumable successful result, because the quantitative variables of snakebite are too divergent. Only when it is understood that the factors in snakebite vary to many extremes will there be concordant opinion on therapy. It has been determined in the laboratory that a viper may introduce its fangs into an animal and inject either an infinitesimal quantity or a deadly dose of venom, decisioned by the serpent's own physical and emotional state. A similar exercise is predictable in the snake's natural environment in the field. A poisonous snakebite may elicit unmistakable fang marks in the skin of the victim without a deposit of detectable venom hypodermically. This patient may be treated in any manner with an unquestionable "cure" and such a case reported would be misleading. We have observed a snakebite in which the fangs have pierced a dog's ear with venom injected into the air instead of the auricle. In addition to the variable of minimal venom injection, there are variables such as snake venom potency from species to species (Table 1), site of envenomation, depth
Study of snakebite Table 1. Illustration of "natural" venom toxicity of a variety of serpents compared in a ratio manner. A tiger snakebite in the natural environment is 1.66 times as dangerous as a coral snakebite regarding mortality and morbidity Relative Venom Toxicity Tiger Snakes (Australian) 20 Mamba Snakes (Africa) . . . . . . . . . . . . . . . . . . .. 15 Cobras (Asia & Africa) . . . . . . . . . . . . . . . . . . .. 15 Coral Snakes 12 Fer-de-Lance Snakes 11 (S. America) 11 Rattlesnakes Cottonmouth Snakes 3 Copperhead Snakes . . . . . . . . . . . . . . . . . . . . . . .. 2 Pygmy Rattlesnakes 2
determined by an experiment. The first group of control animals inoculated with labeled antigen were placed at rest and no treatment was administered. The GeigerMueller counter revealed that only 22% of the venom spread from the site of injection during the first two hours (Fig. 1). If a tourniquet was used, 9% of the injected venom spread and if the limb was placed in a bag of ice there was a 2% spread of venom in one hour. Although the tourniquet and cryotherapy were excellent treatments initially, upon release of the tourniquet and removal of the ice the tagged venom spread rapidly with detrimental results. If the tourniquet was reapplied and released intermittently, as currently published in first aid manuals, the antigen was actually propelled from the limb, ensued by generalized venom intoxication, local edema, ecchymosis, cyanosis and paralysis. Prolonged cryotherapy was subject to frostbite which has proven to be a disastrous complication in snakebite patients. The fast removal of ice application enhances tagged venom release. Incisions coupled with bulb suction retrieved an average of 16% of the labeled antigen in the first 10 minutes and 53.6% in 15 minutes, which proved effectual. Cruciate incisions produced necrosis at their crossings in the soft tissue due to compromised blood supply and these wounds became subject to anaerobic contaminants. Crosshatch scars have been found difficult to correct, especially when placed on the cheeks or forehead where they need plastic surgery for correction. Cruciate incisions are contradictory to basic surgical principles and a single straight incision through the fang punctures is preferable. Mouth suction of a poisonous snakebite wound is mentioned only to rescind this placative measure from the therapeutic regimen. Contrary to some therapists' impressions, alcohol in moderate quantities produced an uptake of 9% of tagged
277
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20
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15
. c:. 0
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Control
10
5
30
60
90
120
Time in Minutes Venom Spread from Envenomed Site
Fig. 1.-Tagged venom injected into a limb reveals that only 22% spreads from the site of injection when the host is at rest and without treatment. Our team debated this finding until such was substantiated in six animals.
venom in 10 minutes, 19% in 20 minutes and 27% in 30 minutes. From these figures it may be assumed that alcohol ingestion is not advocated for snakebite. Exercise proved to be equally detrimental, and therefore one should avoid running after receiving a bite from a venomous serpent. The group study using Wyeth's Polyvalent Antivenin paralleled most other authors' results; that is, the moccasin-venomized animals all survived with a slough of soft tissues when the antivenin was given intravenously. Six animals subjected to rattlesnake antigen and treated 30 minutes later with two vials of intravenous antivenin resulted in two deaths. Six animals more recently treated with one vial of intra-arterial antivenin survived. In a final series of animals subjected to lethal doses of tagged venom, elliptical excisions of the wounds were made after delays of 10, 30, 60 and 120 minutes. The excised specimens were one inch equidistant from the two inoculation punctures and comprised skin, subcutaneous fat and sections of muscles. The scanned specimens surprisingly contained an average of 79% of the injected tagged venom. This slow spread of venom makes possible another satisfactory means of retrieving snake toxin---excision of the bite site. Of the 41 human subjects, 18 had been treated by other physicians using a variety of methods and referred to us. These have been deleted from this study. Of the 23 humans treated entirely by our team, 11 were bitten by the eastern diamondback rattlesnake and eight by the cottonmouth moccasin. All of the bite sites were on the extremities with the exception of one cottonmouth moccasin bite, which was on the left cheek. The post-bite intervals of treatment averaged about 70 minutes, the
Snyder et al
278
shortest time being about 30 minutes and the longest interval about 14 hours. All of the patients except the one with the facial bite were treated with a tourniquet, excision of fang marks and regional intra-arterial antivenin infusion. Some of the wounds were closed per primam and others by skin grafts. There was only one reaction (giant hives) to the horse serum antivenin three days after treatment and this was relieved by intravenous Novocain and oral antihistamines. Based on a decade of animal studies in the laboratory and human clinical cases, we suggest the following therapeutic regimen.
Antigen Diagnosis Because treatment of a nonpoisonous serpent bite has terminated in tragedy, the identity of the offending reptile will influence the mode of treatment. Most venomous antigens cause immediate and prolonged excruciating pain in the bite site area; such is not a conventional symptom of harmless snakebite. The point of fang entrance promptly becomes edematous and circumscribed with petechiae which coalesce to become ecchymotic. The region soon is anesthetic and later paralytic. This sequence of events is not representative of nonpoisonous bites.
Antigen Incarceration A flat nonrigid tourniquet should be positioned between the bite site and the heart and applied tight enough to impede superficial venous and lymphatic return but not to obliterate deep arterial supply or cause ischemia. One should be able to insert a finger without force beneath the tourniquet as a test. Once the tourniquet is satisfactorily applied it should not be removed every 20 minutes as first aid manuals prescribe. Intermittent release and reapplication of a tourniquet significantly perpetuates spread of the venom. Surgeons have maintained pneumatic tourniquets on limbs for two hour intervals without complications.
Antigen Excision With the tourniquet in place, excision of the bite site one inch equidistant from the fang marks and elliptical in fashion is performed. The depth of excision should be to the muscle fascia and include, if involved, small sections of muscle. Enough of the antigen is retrieved by this procedure to save a life without injury to vital structures such as nerves, tendons or large blood vessels. The elliptically contoured wound thus produced lends itself to primary closure at a later date. We are satisfied that an excisional ellipse of skin and subdermal fat is more
efficacious than incision with suction therapy to retrieve the venom. Incision and suction therapy to retrieve venom is advised to the lay public until the patient is under the care of a physician. If incisional therapy is preferred, there should be only one incision, extended through and beyond each fang puncture and deep enough to include some fat. Mechanical suction should be instituted in a vigorous, but not forceful manner for at least 30 minutes, or until a physician can take charge.
Antigen Neutralization Wyeth's Polyvalent Antivenin is our choice; it is administered intra-arterially because it reaches the poisonous venom quicker than intravenous, intramuscular or direct injection surrounding the wound. With the tourniquet in position, the antivenin is pumped into the brachial artery for upper extremity bites, into the femoral artery for lower extremity bites and into the common carotid artery for head bites. Of course, a tourniquet is not used in the latter method of administration. For administration, the vial of antivenin is mixed in 100 m!. of sterile normal saline solution to which is added 100 mg. of hydrocortisone sodium succinate (Solu-Cortef, Upjohn Co.) to cover possible horse serum reaction; this mixture is then pumped into the artery with a sphygmomanometer bulb. It takes about 20 minutes for administration. A skin text for horse serum sensitivity is advised in patients with known allergy; if the reaction is positive, the treatment course should be altered to the severity of the snakebite. Antivenin given subcutaneously and intramuscularly does not contact venom in the tissues as rapidly as does intravenously administered antivenin, nor does the intravenous approach work as rapidly as does the intra-arterial because antivenin given intravenously must be returned to the heart and then eventually distributed to the bite site via the arterial system. Horse serum reactions following the intravascular administration of the material actually respond quicker to therapy than do reactions following horse serum given extra-vascularly (intramuscular or subcutaneous). Antivenin perfusion intra-arterially is the preferred route.
Antigen Symptom Therapy Pain will vary according to body weight and pain threshold of the patient and initially may be relieved through the use of narcotics. Later, milder analgesics will suffice. Shock is treated with circulatory expanders, colloids and electrolytes, and the usual supportive measure. Edema is reduced by judged semielevation of the bite site. Certain antihistamines are synergistic with snake venom and therefore contraindicated. Initially, we were apprehensive
Study of snakebite
regarding the findings in this specific antihistamine group experiment, so the project was repeated. The results proved that some antihistarninic drugs stimulated the action of the snakebite poison, thus accelerating death. Possible clostridial infections are prevented by early inoculation and continuous wound cleansings. Corticoids prolong life but are not lifesaving. Antibiotics are used in relation to the accident severity. Routine hemogram and urogram tests are utilized. All poisonous snakebite victims should be hospitalized for 24 hours for observation.
279
Given specific situations, these measures may be administered entirely by the physician or in part by the layman. Certain lay people such as boy scouts, conservation officers, game wardens, state troopers and service paramedical personnel are assumed to have knowledge of the first aid principles of tourniquet application, incising, suction and dressing of wounds. Definitive therapy such as excising and vascular administration of fluids is definitely dependent upon professional medical care.
LESSONS FROM HISTORY
A Definitive Study of Snakebite' C. C. SNYDER, M.D., J. E. PICKINS, M.D., R. P. KNOWLES, D.V.M., J. L. EMERSON, and W. A. HINES of injection and the variable of the victim's blood volume. The lethal doses of various snake venoms are dependent upon the pharmacologic complexity of the venom and the venom action in the tissues that are attacked. Injections of venom deep into the large muscle mass in the lower extremity is more detrimental than antigen injected into the forehead or scalp because action of the moving leg muscles spreads the poison, therefore creating difficulty in retrieving it. Also, in comparison, the scalp muscles tend to move less and the skull bone does not permit deep penetration, thus providing for easier removal of the antigen. Children, with a comparatively small blood volume, experience severe envenomation reaction because of venom concentration; the larger blood volume of an adult provides more diluent for the toxin, consequently rendering it less potent. The ratio of venom injected to victim's blood volume is the reason children necessitate more vigorous therapy to combat the effects of snakebite. Mindful of these variables, we outlined an investigation a decade ago to study the effects of snake venoms, to evaluate conventional treatments as well as other methods of therapy and to ascertain which treatments contribute to the best results. The four types of poisonous snakes in the United States are the rattlesnake, moccasin, copperhead and coral snake. The experiment was devoted to the venoms of the cottonmouth water moccasin (Ancistrodon piscivorus) and the eastern diamondback rattlesnake (Crotalus adamanteus). The poisons were introduced by natural bites of the snakes as well as purified venom injections labeled with Iodine 131 . Control subjects were included in the 139 canines which constituted the nucleus of the experimental effort. Many of these animals were later given away as pets. There were 41 human subjects of whom Dr. Snyder is formerly clinical associate professor of plastic surgery, 19 were bitten by the eastern diamondback rattlesnake, University of Miami School of Medicine. 10 were victims of pygmy or ground rattlesnakes and 12 From the Departments of Surgery, University of Utah College of Medreceived cottonmouth moccasin bites. Therapeutic meaicine and Veterans Administration Hospital, Salt Lake City, Utah. sures evaluated included use of the tourniquet, cryo1 Excerpt reprinted with permission from the J Fla Med Assoc, Vol therapy, cruciate incisions, linear incisions, excisions, 55, No 4, April 1968, pp 330-337. Original style, spelling, and puncsuction, alcohol ingestion, rest and activity. tuation have been retained. Several figures have not been used, owing All of the animal subjects which were injected with to the difficulty of reproducing them. Figures 5 and 9 have been rethe isotope-tagged venom were given lethal doses preproduced as Table 1 and Figure 1, respectively.
Many therapeutic traditions for poisonous snakebite terminate short of expectation. The mortality rate is not disastrously high, but the morbidity is frequently prolonged with the resultant physical disability and financial loss. More published reports exist concerning serpentine envenomation than most readers have time to peruse. Unfortunately, many of these offer personal opinions in good faith which actually are of little value and occasionally are harmful. These clinical reports of snakebite patients confuse the inexperienced therapist and may lead to dreadful sequelae. Therapeutic rationale of envenomation will never be determined by treating an occasional victim with a presumable successful result, because the quantitative variables of snakebite are too divergent. Only when it is understood that the factors in snakebite vary to many extremes will there be concordant opinion on therapy. It has been determined in the laboratory that a viper may introduce its fangs into an animal and inject either an infinitesimal quantity or a deadly dose of venom, decisioned by the serpent's own physical and emotional state. A similar exercise is predictable in the snake's natural environment in the field. A poisonous snakebite may elicit unmistakable fang marks in the skin of the victim without a deposit of detectable venom hypodermically. This patient may be treated in any manner with an unquestionable "cure" and such a case reported would be misleading. We have observed a snakebite in which the fangs have pierced a dog's ear with venom injected into the air instead of the auricle. In addition to the variable of minimal venom injection, there are variables such as snake venom potency from species to species (Table 1), site of envenomation, depth
Study of snakebite Table 1. Illustration of "natural" venom toxicity of a variety of serpents compared in a ratio manner. A tiger snakebite in the natural environment is 1.66 times as dangerous as a coral snakebite regarding mortality and morbidity Relative Venom Toxicity Tiger Snakes (Australian) 20 Mamba Snakes (Africa) . . . . . . . . . . . . . . . . . . .. 15 Cobras (Asia & Africa) . . . . . . . . . . . . . . . . . . .. 15 Coral Snakes 12 Fer-de-Lance Snakes 11 (S. America) 11 Rattlesnakes Cottonmouth Snakes 3 Copperhead Snakes . . . . . . . . . . . . . . . . . . . . . . .. 2 Pygmy Rattlesnakes 2
determined by an experiment. The first group of control animals inoculated with labeled antigen were placed at rest and no treatment was administered. The GeigerMueller counter revealed that only 22% of the venom spread from the site of injection during the first two hours (Fig. 1). If a tourniquet was used, 9% of the injected venom spread and if the limb was placed in a bag of ice there was a 2% spread of venom in one hour. Although the tourniquet and cryotherapy were excellent treatments initially, upon release of the tourniquet and removal of the ice the tagged venom spread rapidly with detrimental results. If the tourniquet was reapplied and released intermittently, as currently published in first aid manuals, the antigen was actually propelled from the limb, ensued by generalized venom intoxication, local edema, ecchymosis, cyanosis and paralysis. Prolonged cryotherapy was subject to frostbite which has proven to be a disastrous complication in snakebite patients. The fast removal of ice application enhances tagged venom release. Incisions coupled with bulb suction retrieved an average of 16% of the labeled antigen in the first 10 minutes and 53.6% in 15 minutes, which proved effectual. Cruciate incisions produced necrosis at their crossings in the soft tissue due to compromised blood supply and these wounds became subject to anaerobic contaminants. Crosshatch scars have been found difficult to correct, especially when placed on the cheeks or forehead where they need plastic surgery for correction. Cruciate incisions are contradictory to basic surgical principles and a single straight incision through the fang punctures is preferable. Mouth suction of a poisonous snakebite wound is mentioned only to rescind this placative measure from the therapeutic regimen. Contrary to some therapists' impressions, alcohol in moderate quantities produced an uptake of 9% of tagged
277
...
25
.,<>.
"~
20
E
15
. c:. 0
c: >
'0 u
~
Control
10
5
30
60
90
120
Time in Minutes Venom Spread from Envenomed Site
Fig. 1.-Tagged venom injected into a limb reveals that only 22% spreads from the site of injection when the host is at rest and without treatment. Our team debated this finding until such was substantiated in six animals.
venom in 10 minutes, 19% in 20 minutes and 27% in 30 minutes. From these figures it may be assumed that alcohol ingestion is not advocated for snakebite. Exercise proved to be equally detrimental, and therefore one should avoid running after receiving a bite from a venomous serpent. The group study using Wyeth's Polyvalent Antivenin paralleled most other authors' results; that is, the moccasin-venomized animals all survived with a slough of soft tissues when the antivenin was given intravenously. Six animals subjected to rattlesnake antigen and treated 30 minutes later with two vials of intravenous antivenin resulted in two deaths. Six animals more recently treated with one vial of intra-arterial antivenin survived. In a final series of animals subjected to lethal doses of tagged venom, elliptical excisions of the wounds were made after delays of 10, 30, 60 and 120 minutes. The excised specimens were one inch equidistant from the two inoculation punctures and comprised skin, subcutaneous fat and sections of muscles. The scanned specimens surprisingly contained an average of 79% of the injected tagged venom. This slow spread of venom makes possible another satisfactory means of retrieving snake toxin---excision of the bite site. Of the 41 human subjects, 18 had been treated by other physicians using a variety of methods and referred to us. These have been deleted from this study. Of the 23 humans treated entirely by our team, 11 were bitten by the eastern diamondback rattlesnake and eight by the cottonmouth moccasin. All of the bite sites were on the extremities with the exception of one cottonmouth moccasin bite, which was on the left cheek. The post-bite intervals of treatment averaged about 70 minutes, the
Snyder et al
278
shortest time being about 30 minutes and the longest interval about 14 hours. All of the patients except the one with the facial bite were treated with a tourniquet, excision of fang marks and regional intra-arterial antivenin infusion. Some of the wounds were closed per primam and others by skin grafts. There was only one reaction (giant hives) to the horse serum antivenin three days after treatment and this was relieved by intravenous Novocain and oral antihistamines. Based on a decade of animal studies in the laboratory and human clinical cases, we suggest the following therapeutic regimen.
Antigen Diagnosis Because treatment of a nonpoisonous serpent bite has terminated in tragedy, the identity of the offending reptile will influence the mode of treatment. Most venomous antigens cause immediate and prolonged excruciating pain in the bite site area; such is not a conventional symptom of harmless snakebite. The point of fang entrance promptly becomes edematous and circumscribed with petechiae which coalesce to become ecchymotic. The region soon is anesthetic and later paralytic. This sequence of events is not representative of nonpoisonous bites.
Antigen Incarceration A flat nonrigid tourniquet should be positioned between the bite site and the heart and applied tight enough to impede superficial venous and lymphatic return but not to obliterate deep arterial supply or cause ischemia. One should be able to insert a finger without force beneath the tourniquet as a test. Once the tourniquet is satisfactorily applied it should not be removed every 20 minutes as first aid manuals prescribe. Intermittent release and reapplication of a tourniquet significantly perpetuates spread of the venom. Surgeons have maintained pneumatic tourniquets on limbs for two hour intervals without complications.
Antigen Excision With the tourniquet in place, excision of the bite site one inch equidistant from the fang marks and elliptical in fashion is performed. The depth of excision should be to the muscle fascia and include, if involved, small sections of muscle. Enough of the antigen is retrieved by this procedure to save a life without injury to vital structures such as nerves, tendons or large blood vessels. The elliptically contoured wound thus produced lends itself to primary closure at a later date. We are satisfied that an excisional ellipse of skin and subdermal fat is more
efficacious than incision with suction therapy to retrieve the venom. Incision and suction therapy to retrieve venom is advised to the lay public until the patient is under the care of a physician. If incisional therapy is preferred, there should be only one incision, extended through and beyond each fang puncture and deep enough to include some fat. Mechanical suction should be instituted in a vigorous, but not forceful manner for at least 30 minutes, or until a physician can take charge.
Antigen Neutralization Wyeth's Polyvalent Antivenin is our choice; it is administered intra-arterially because it reaches the poisonous venom quicker than intravenous, intramuscular or direct injection surrounding the wound. With the tourniquet in position, the antivenin is pumped into the brachial artery for upper extremity bites, into the femoral artery for lower extremity bites and into the common carotid artery for head bites. Of course, a tourniquet is not used in the latter method of administration. For administration, the vial of antivenin is mixed in 100 m!. of sterile normal saline solution to which is added 100 mg. of hydrocortisone sodium succinate (Solu-Cortef, Upjohn Co.) to cover possible horse serum reaction; this mixture is then pumped into the artery with a sphygmomanometer bulb. It takes about 20 minutes for administration. A skin text for horse serum sensitivity is advised in patients with known allergy; if the reaction is positive, the treatment course should be altered to the severity of the snakebite. Antivenin given subcutaneously and intramuscularly does not contact venom in the tissues as rapidly as does intravenously administered antivenin, nor does the intravenous approach work as rapidly as does the intra-arterial because antivenin given intravenously must be returned to the heart and then eventually distributed to the bite site via the arterial system. Horse serum reactions following the intravascular administration of the material actually respond quicker to therapy than do reactions following horse serum given extra-vascularly (intramuscular or subcutaneous). Antivenin perfusion intra-arterially is the preferred route.
Antigen Symptom Therapy Pain will vary according to body weight and pain threshold of the patient and initially may be relieved through the use of narcotics. Later, milder analgesics will suffice. Shock is treated with circulatory expanders, colloids and electrolytes, and the usual supportive measure. Edema is reduced by judged semielevation of the bite site. Certain antihistamines are synergistic with snake venom and therefore contraindicated. Initially, we were apprehensive
Study of snakebite
regarding the findings in this specific antihistamine group experiment, so the project was repeated. The results proved that some antihistarninic drugs stimulated the action of the snakebite poison, thus accelerating death. Possible clostridial infections are prevented by early inoculation and continuous wound cleansings. Corticoids prolong life but are not lifesaving. Antibiotics are used in relation to the accident severity. Routine hemogram and urogram tests are utilized. All poisonous snakebite victims should be hospitalized for 24 hours for observation.
279
Given specific situations, these measures may be administered entirely by the physician or in part by the layman. Certain lay people such as boy scouts, conservation officers, game wardens, state troopers and service paramedical personnel are assumed to have knowledge of the first aid principles of tourniquet application, incising, suction and dressing of wounds. Definitive therapy such as excising and vascular administration of fluids is definitely dependent upon professional medical care.