IMMEDIATE FIRST AID
for bites by
In the event of an actual or probable bite from a Long-nosed Viper, execute the following first aid measures without delay.
- Make sure that the responsible snake or snakes have been appropriately and safely contained, and are out of danger of inflicting any additional bites.
- Immediately call for transportation.
- Keep the victim calm and reassured. Allow him or her to lie flat and avoid as much movement as possible. If possible, allow the bitten limb to rest at a level lower than the victim's heart.
- Identify the bite site, looking for fang marks, and apply the Sawyer Pump extractor with the largest cup possible over the bite site. If there are two or more fang marks noted on the limb, apply the pump extractor over at least one fang mark. If more than one pump extractor is available, they may be applied to the additional fang marks.
- Immediately wrap a large constricting bandage snugly about the bitten limb at a level just above the bite site, i.e., between the bite site and the heart. The constricting band should be as tight as one might bind a sprained ankle, but not so tight as to constrict blood flow. Immobilize the affected extremity with a splint.
- DO NOT remove the constricting band or splint until the victim has reached the hospital and is receiving Antivenom.
- Have the Behring Vorderer/Mittlerer Orient Polyvalent Antivenom ready for the Lifeflight crew to take with the victim to the hospital. Give them the following:
- the available antivenom (at least 15 vials)
- the accompanying instruction (Protocol) packet
- the victim's medical packet
DO NOT cut or incise the bite site
DO NOT apply ice to the bite site
Summary for Human Bite
The bite of the Long-nosed Viper is rarely fatal. Victims will usually complain of pain at the bite site and local swelling may be evident. Local tissue destruction can ensue. Please read the attached Medical Management Protocol and respond appropriately.
- First Aid:
- Apply a constricting band and splint, if not already present, as described in the Immediate First Aid section. Rest this extremity below the level of the patient's heart (if practical).
- Transport to U.C.S.D. Medical Center Trauma Service.
- Medical Management:
- Call your local Poison Control Center, or the San Diego Regional Poison Control Center (800 876-4766). They should locate a consultant to help you treat this patient.
- Observe for Signs and Symptoms of Envenomation.
- If significant systemic signs or symptoms are present, perform the following:
- Administer Lactated Ringers Solution at 250 mls per hour.
- Draw samples and collect initial laboratory data.
- Dilute the contents of 2 vials of Behring Vorderer/Mittlerer Orient Polyvalent Antivenom in Lactated Ringers Solution to a total volume of 100ml. Administer the antivenom I.V. piggyback over 30 minutes at a rate of 200ml/hour (i.e. one vial per 15 minutes). The combined rate of diluted antivenom and Lactated Ringers Solution is now approximately 450ml/hour. The rate of Lactated Ringers Solution may be adjusted accordingly to avoid fluid overload, however a brisk urine output should be a treatment goal.
- When one complete vial has been infused (i.e. 15 minutes), remove the constricting band and splint.
If symptoms progress rapidly, reapply the bandage, wait 10 minutes, and then again release the bandage slowly while antivenom administration is continuing.
- Allergic or untoward reactions to the antivenom should be treated with Benadryl, Epinephrine, and/or Corticosteroids. A patient with known sensitivity to horse serum may be pretreated with 1 gm of Solumedrol, administered I.V. push.
- Monitor Signs, Symptoms, and Laboratory data, and administer additional antivenom in 2 vial increments at a rate of one vial every 15 minutes as necessary to control the progression of symptoms.
- The required amount of antivenom will vary with the severity of envenomation. One should anticipate using (including the initial dose):
2-4 vials for a minor bite with envenomation
15 vials may be necessary for moderate or severe bites.
for bites by
This person has received a bite and probable envenomation from a Long-nosed Viper (Vipera ammodytes). This is a very venomous and dangerous snake native to Southeastern Europe and Asia Minor. Although fatalities are rare with proper treatment, envenomation may result in a wide spectrum of clinical manifestations including local tissue destruction, cardiovascular collapse, and coagulopathy.
Please read and execute the following procedures without delay.
- A constricting band and splint have been applied as immediate first aid adjuncts to retard the absorption of the venom. DO NOT remove until the patient has arrived at the hospital and is receiving the antivenom.
- Make sure that at least 15 vials of Behring Vorderer/Mittlerer Orient Polyvalent Antivenom are present with the patient. This antivenom is specific and is only available directly from the San Diego Zoo Reptile Department. Refrigerate the antivenom upon arrival to the hospital.
- If the patient has been envenomated, the initial treatment is two vials of intravenous antivenom. Envenomation is diagnosed by the presence of characteristic signs and symptoms. Necessary information follows and is organized into the following sections:
- Signs and Symptoms of Envenomation
- Medical Management
- General Considerations
- Special Considerations
Signs and Symptoms of Envenomation:
- Local Affects:
- Pain and swelling
- Hemorrhagic edema
- Blistering, bleb formation
- Tissue necrosis:
- Circulatory shock
- Coagulation defects
- Neutrophil leucocytosis
- Spontaneous bleeding
- Gastrointestinal bleeding
- Respiratory depression
- Pulmonary congestion
- Renal Failure
- Abdominal pain
- Regional lymphadenopathy
- Edema of tongue, face, lips
- Faintness, dizziness
- Fang Marks: The presence of fang marks does not always imply envenomation as the Long-nosed Viper may bite without injecting venom into the victim. However, the absence of fang marks does not necessarily preclude the possibility of a bite, nor does it give any indication of the severity of the bite. Fang marks may be present
as one or more well defined punctures, as a series of small lacerations or scratches, or there may not be any noticeable or obvious markings where the bite occurred. Finally, multiple bites inflicted by a single snake are possible and should be noted if present.
- Admit patient to the Trauma Service and call consultants listed on the last page. Terence M. Davidson, M.D. is the local consultant for snake bites, and should be notified immediately.
- Begin a peripheral intravenous infusion (16 gauge catheter) of Lactated Ringers Solution at a rate of 250 cc/hour.
- Draw blood from the contralateral arm, and collect urine for the following laboratory tests. Mark STAT.
- Type and Cross Match TWO units of Whole blood.
- CBC with differential and quantitative platelet count.
- Coagulation Parameters:
- Prothrombin Time (PT)
- Partial Thromboplastin Time (PTT)
- Fibrinogen Levels
- Fibrin Degradation Products
- Serum Electrolytes, BUN/Creatinine, Calcium, Phosphorus.
- Lactate Dehydrogenase (with Isoenzyme analysis). Isoenzyme analysis may indicate multiple targets of the venom components which may dictate further management.
- Urinalysis (Macroscopic and Microscopic Analysis). Must include analysis for:
- Free Protein
- Electrocardiogram (Sinus Tachycardia would be expected).
- Continuous Urine Output Monitoring (In dwelling Foley Catheter if unconscious). Watch for possible oliguria or anuria.
- Additional tests as needed or indicated by the patient's hospital course.
- It may be necessary or practical to repeat some of the above serum and urine tests over the hospital course to monitor the effects of antivenom therapy or to detect late changes in laboratory values.
- OBSERVE PATIENT CLOSELY for signs and symptoms of envenomation which usually manifest between 15 minutes and two hours after the bite occurred.
- If NONE of the signs or symptoms have been noted after TWO hours, there is the possibility that the patient received a dry bite (no venom injected).
- VERY SLOWLY begin to remove the constricting band and splint watching carefully for any changes in the patient's status. If any changes occur, assume the patient has been envenomated and prepare to give antivenom immediately (as directed below).
- If signs and symptoms still fail to manifest, continue CLOSE observation of the patient for an additional 12 to 24 hours.
- IF SIGNIFICANT SYSTEMIC SIGNS OR SYMPTOMS become apparent, begin antivenom therapy as follows:
- Dilute the contents of 2 vials of Behring Vorderer/ Mittlerer Orient Polyvalent Antivenom in Lactated Ringers Solution to a total volume of 100ml. Administer the antivenom I.V. piggyback over 30 minutes at a rate of 200ml/hour (i.e. one vial per 15 minutes). The combined rate of diluted antivenom and Lactated Ringers Solution may be adjusted accordingly to avoid fluid overload, however a brisk urine output should be a treatment goal.
- Should any signs of ALLERGY/ANAPHYLAXIS (e.g., coughing, dyspnea, urticaria, itching, increased oral secretions, etc.) develop, immediately discontinue the administration of antivenom, and treat symptoms with Corticosteroids, Epinephrine, Benadryl, Atarax and/or Antihistamines. As soon as the patient is stabilized, continue the antivenom infusion at a slower rate. (i.e. 120ml/hour).
- After 15 minutes of antivenom administration, the splint and the constricting band may be removed. If the patient's condition worsens, reapply the bandage, wait 10 minutes and release the bandage again slowly while antivenom administration is continuing.
- Antivenom Therapy is the mainstay of treatment for Long-nosed Viper snake envenomation. Many of the symptoms are ameliorated or entirely eliminated by the antivenom alone. Other symptoms will require additional therapeutic modalities in order to be corrected.
- Cardiovascular status: The administration of antivenom alone will help correct hypotension, bradycardia, and signs of circulatory shock provided the patient is not hypovolemic. Intravenous administration of Lactated Ringers Solution is warranted in all cases. Cardiovascular stability and a brisk diuresis are desired.
- Hematological symptoms may present as Disseminated Intravascular Coagulopathy (DIC), and are treated essentially as other DIC's
- Neurological symptoms are uncommon with Long-nosed Viper bites. However, if breathing becomes impaired, respiratory assistance may be necessary. As such intubation and ventilation may be appropriate adjuncts in certain clinical settings. Secretions may become copious, necessitating suctioning.
- It is important to keep venom neutralization current and continuous. The best method to accomplish this is to monitor the patient's status. If the present condition does not improve, or should it worsen for any reason, additional antivenom should be administered. Give all additional antivenom in two vial increments. Dilute the antivenom in Lactated Ringers as before and administer the antivenom I.V. piggyback over approximately 30 minutes. Minor bites with envenomation require at least 2-4 vials but severe envenomations may require up to 15 vials of antivenom.
- It is advisable to perform periodic serum and urine analyses during therapy (as outlined above).
- It is always best to keep the patient in an Intensive Care setting until free of major symptoms for 24 hours. The patient should be observed in the hospital for at least 24 hours after all symptoms abate
- It is important that the patient remain resting and warm. Avoid unnecessary movement.
- Symptom variability: There is a marked variability of symptoms in response to a Long-nosed Viper bite. It is important to note the continual progression of signs and symptoms throughout the course of therapy and to give additional antivenom as necessary.
- Circulatory Shock: Hypotension and bradycardia are frequent complications of Long-nosed Viper bites. Plasma expanders and/or vasopressor agents may be given when appropriate, but will be most effective if adequate antivenom has been appropriately administered.
- Fluid Management: The patient should be well hydrated, and a brisk urine output should be maintained. Blood products should not be given until circulating venom has been neutralized with antivenom.
- Compartment Syndrome: It should be noted that fascial compartment syndromes in Long-nosed Viper bites are uncommon. Limbs may swell significantly, but rarely involve specific fascially bound compartments. If however the logistics of the bite raise a high index of suspicion for compartment syndrome, monitoring with a Wick Catheter or appropriate pressure device may be necessary. Fasciotomy is rarely, if ever, recommended.
- Tetanus Prophylaxis should be current.
- Antibiotics are not recommended prophylactically.
- Antivenom is the best treatment for all signs and symptoms of Long-nosed Viper bites and should be utilized prior to other treatment modalities.
- Multiple Bites:
- It is possible for a Long-nosed Viper to deliver more than one bite in a single attack. If there is evidence that such an attack occurred (i.e., history or multiple bite sites), give 4 vials of antivenom as the initial dose but be prepared to give a total of 15 vials to adequately treat the bite. Titrate antivenom administration to signs and symptoms as discussed previously.
- Testing for Equine Protein Sensitivity:
- It is NOT ADVISABLE to utilize subcutaneous or intradermal testing for sensitivity to equine products in that such testing may be unreliable, and may unnecessarily delay antivenom therapy which must be used if any signs of Long-nosed Viper envenomation are present.
- If there is reason to believe that the patient may be sensitive to equine protein products:
- Premedicate the patient with 1 gm Solumedrol, administered I.V. push. Assuming the patient's condition is stable, wait 15-30 minutes before administering the antivenom.
- Administer the diluted antivenom at a rate as tolerated by the patient beginning at a rate of 100ml/hour (as opposed to the normal 200ml/hour rate). If the patient tolerates this, increase the rate up to 200ml/hour.
- Monitor Pulse and Blood Pressure carefully. Be prepared to treat for Anaphylaxis.
- Clinical Experience with the Long-nosed Viper
- The Long-nosed Viper is considered to be sedentary and shy by nature but is quick to strike if bothered. It is the most dangerous European viper and its venom is quite toxic, however the toxicity of its venom varies with the range of the species.
- Complications of human envenomation by the Long-nosed Viper are variable but frequently signs and symptoms are limited to local manifestations. Fatalities are very infrequent especially if antivenom is administered in a timely manner.
The following references are recommended for further reading. This material includes case histories, guidelines and recent findings in treatment of Long-nosed Viper bites. These should be read only after treatment has begun, and the patient is stable.
- Jackson, O.F., Effects of a bite by a sand viper (Vipera ammodytes), The Lancet, September 27, 1980, 686-687.
- Reid, H.A., Adder bites in Britain, British Medical Journal. 1976,2:153-156.
- Sket, D., Gubensek, F., Adamic, S., and Lebez, D., Action of a partially purified basic protein fraction from Vipera ammodytes venom, Toxicon. 1973, 11:47-53.