IMMEDIATE FIRST AID
for bites by
In the event of an actual or probable bite from a King Cobra, 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.
- Immediately wrap a large crepe bandage snugly around the bitten limb starting at the site of the bite and working proximally up the limb (the full length if possible). The bandage should be as tight as one might bind a sprained ankle. (See attached copy from "First Aid for Snakebite" by Dr. S.K. Sutherland.)
- Secure the splint to the bandaged limb to keep the limb as rigid and unmoving as possible. Avoid bending or moving the limb excessively while applying the splint.
- DO NOT remove the splint or bandages until the victim has reached the hospital and is receiving Antivenom.
- Have the TIGER SNAKE ANTIVENOM (Commonwealth Serum Laboratories) ready for the emergency crew to take with the victim to the hospital. Give them the following:
- the available antivenom (at least 10 vials)
- the accompanying instruction (Protocol) packet
- the victim's medical packet (if available)
DO NOT cut or incise the bite site
DO NOT apply ice to the bite site
Summary for Human Bite
The bite of the King Cobra with envenomation can be rapidly fatal (as early as 30 minutes). Please read the attached Medical Management Protocol and respond appropriately.
- First Aid:
- Bandage and Immobilize the bitten limb with crepe bandages and splint as described in the Immediate First Aid section. Rest this extremity below the level of the patient's heart (if practical).
- Transport to a medical center emergency or 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 signs or symptoms are present, perform the following:
- Administer Lactated Ringers Solution at 200 to 250 mls per hour.
- Draw samples and collect initial laboratory data.
- Dilute the contents of 2 vials (6000 units) of Commonwealth Serum Laboratories Tiger Snake Antivenom 1:10 in Lactated Ringers Solution. Adminster the antivenom I.V. piggyback over 30 minutes at a rate of 200 units per minute.
Note: Tiger Snake Antivenom is the prefered antivenom of choice in treating King Cobra bites. It has a high neutralizing paraspecificity.
- Remove the splints and crepe bandage slowly over a period of 10 minutes. If symptoms progress rapidly, reapply the bandage, and administer an additional 2 vials. Again attempt to remove the bandage.
- Allergic or untoward reactions to the antivenom should be treated with Corticosteroids, Epinephrine, Benadryl, Atarax and/or Antihistamines as appropriate.
- Monitor Signs, Symptoms, and Laboratory data, and administer additional antivenom in 1 vial (3000 units) increments at a rate of 100 units per minute as necessary to control the progession of symptoms.
- The required amount of antivenom will vary with the severity of envenomation. One should anticipate using (including the initial dose):
4-6 vials total for a minor bite with envenomation.
8-20 vials total may be necessary for moderate or severe bites.
for bites by
This person has received a bite and probable envenomation from a King Cobra (Ophiophagus hannah). This is a very venomous and dangerous snake which is widely distributed in India, China, Malaysia, Indonesia, Southeast Asia, and as far as the Philippines. The King Cobra is the largest venomous snake in the world, and can inject an extremely large quantity of venom in one bite. Envenomation signifies a true medical emergency. In this particular species, envenomation usually presents predominately with systemic neurologic manifestations. Drowsiness, neurological and neuromuscular symptoms may develop early; paralysis, ventilatory failure or death often ensue rapidly.
Please read and execute the following procedures without delay.
- A crepe bandage 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 10 vials of Tiger Snake Antivenom are present with the patient. This antivenom is strongly paraspecific, and contains the appropriate fractions necessary to neutralize the components of King Cobra venom.
- If the patient has been envenomated, the treatment is 4 to 15 vials of intravenous antivenom. Envenomation is diagnosed by the presence of characteristic signs and symptoms. Necessary information follows and is organized in sections:
- Signs and Symptoms of Envenomation
- Medical Management
- General Considerations
- Special Considerations
Signs and Symptoms of Envenomation:
- Neurological and Neuromuscular: These signs and symptoms if they are to occur will usually manifest earliest (possibly within 15 to 30 minutes following the bite). Not all of these will necessarily develop, even with severe envenomation.
- Eyelid drooping (Ptosis)
- Respiratory paralysis or Dyspnea (often severe apnea with early onset)
- Palatal paralysis
- Glossopharyngeal paralysis
- Limb paralysis
- Head drooping (Cervical muscle paresis or paralysis)
- Hyporeflexia (generalized)
- Sudden loss of consciousness
- Stumbling gait (Ataxia)
- General: These symptoms typically manifest within one to four hours following the bite if envenomation occurred. Pain will usually begin immediately after the bite.
- Hypotension with irregular Peripheral Pulses
- Generalized Shock
- Flushing of the face
- Warm skin
- Pain around bite site
- Nausea and Vomiting
- Abdominal Pain
- Urticaria and Fever
- Cardiotoxicity: Direct clinical cardiotoxic effects have not yet been reported in King Cobra envenomations. These have been recorded in some cobra and other elapid envenomations. Clinical monitoring of cardiac function and rhythm would be advised.
- Renal: Nephrotoxic effects have likewise not been reported with the King Cobra, but have been seen in Mamba, Tiger Snake, Taipan and other elapid envenomations. Oliguria or Anuria with possible changes in urinary composition will herald the development of renal shutdown. Dialysis is advised.
- Local Symptoms: In some cases of King Cobra bite, local tissue destruction and necrosis may be extensive. Swelling may extend proximally on the bitten extremity with bleb formation. Gangrene requiring amputation can occur. Local tissue damage may include:
- Localized dusky discoloration of skin
- Serosanguineous vesiculation
- Secondary bacterial infection (Proteus vulgaris was cultured in one case)
- Necrosis with tissue sloughing (can be extensive, but will likely remain localized to the bite site)
- Local edema
- Swelling (may extend proximally)
- Fang Marks: 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. The absence of fang marks does not preclude the possibility of a bite (especially if a juvenile snake is involved). In general, the fang marks from a King Cobra are large, well defined and spaced apart with slight bleeding from the marks. Multiple bites inflicted by a single snake or by more than one snake are also possible, and should be noted if present (See Special Considerations below). The presence of fang marks does not always imply that the injection or deposition of venom into the bite wound (envenomation) actually occurred. In some cases, the snake may voluntarily elect not to inject venom with the strike resulting in a dry bite.
- Admit patient to an emergency or trauma service and call the consultant identified by the Poison Control Center.
- 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 platelets.
- 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:
- Urine Electrolytes and Creatinine
- Free Protein
- Electrocardiogram (Place the patient on continuous monitoring). Rapid heart rate to be expected.
- Continuous Urine Output Monitoring (Indwelling Foley Catheter if unconscious). Watch for possible oliguria or anuria.
- Additional Tests as needed or indicated by patient's hospital course.
- It may be necessary or practical to repeat some of the above serum and urine tests periodically over the hospital course to monitor the effects of antivenom therapy or to detect late changes in parametric values.
- OBSERVE PATIENT CLOSELY for signs and symptoms of envenomation which usually manifest between 15 minutes and two hours following the bite.
- 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 bandages and splint watching carefully for any changes in the patient's status. If any changes occur, assume the patient has been envenomed 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 24 hours.
- IF ANY SIGN OR SYMPTOM becomes apparent or has been noted during the course of treatment, begin Antivenom Therapy as follows:
- Dilute the contents of TWO vials of Tiger Snake Antivenom (6000 units) in Lactated Ringers Solution (Hartmann's Solution) to a total volume of 120 mls.
- Administer the diluted Antivenom intravenously over a period of 30 minutes at a rate of 4 mls per minute (i.e., 2 vials per 30 minutes or 200 units per minute).
- 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 Epinephrine, Steroids and Antihistamines. As soon as the patient is stabilized, continue the antivenom infusion at a slower rate.
- After 15 minutes of antivenom administration, the splint and the bandages may be removed. This should be done VERY SLOWLY over a period of FIVE minutes to prevent a bolus release of venom. If the patient's condition worsens, reapply the crepe bandage, wait 10 minutes and release the bandage again slowly over 10 minutes while antivenom administration is continuing.
- Antivenom Therapy is the mainstay of treatment for King Cobra envenomation. Many of the symptoms are ameliorated or entirely eliminated by the antivenom alone. Other symptoms will require additional modalities of therapy to correct.
- Neurological Symptoms (especially respiratory obstruction or failure) tend to predominate the clinical picture in cases of King Cobra envenomation, and are usually the most immediate cause of dangerous problems. Often, these are improved by the antivenom. If breathing becomes impaired, provide respiratory assistance. Secretions may become copious, necessitating suctioning or even intubation.
- Hematological symptoms may present as a Disseminated Intravascular Coagulopathy, and are treated as are other DICs. This, however, has not yet been reported with King Cobra envenomation.
- Renal symptoms may complicate the situation, and if severe (i.e., Acute Renal Failure) may necessitate Peritoneal Dialysis.
- If severe muscle or respiratory paralysis develops and persists, administer 0.6 mg of Atropine IV. Follow by giving 0.5 mg of Neostigmine IV every 30 minutes for a maximum of FIVE doses.
- If the bite site develops signs suggestive of infection, Cultures and Sensitivities should be obtained prior to starting appropriate Antibiotic therapy.
- It is important to keep venom neutralization current and continuous. The best method to accomplish this is to keep a close watch on 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 1 vial (3000 unit) doses. Dilute one vial in Lactated Ringers Solution to a total volume of 60 mls and deliver I.V piggyback over 30 minutes at a rate of 2 mls per minute (i.e., 1 vial per 30 minutes or 100 units per minute). One should anticipate using (including the Initial dose):
4-6 vials total for a minor bite with envenomation.
8-20 vials total may be necessary for moderate or severe bites.
- 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 symptoms are stabilized.
- It is important that the patient be placed at rest, kept warm, and avoid unnecessary movement.
- The onset of dangerous Neurotoxic symptoms can be rapid and subtle. In addition, they are more rapidly reversed in their early stages than when fully developed. It may be necessary to wake the patient and perform a brief neurologic check every hour or so to assure that breathing and other vital functions are not impaired. Carefully note the progress of any paralysis which may be present.
- Respiratory obstruction and failure are the greatest immediate concern. Should the patient develop difficulties in breathing or airway impairment, respiratory support will be required. If the tongue, jaw or pharynx become paralyzed, insert an oral airway. Make sure adequate suction equipment is available and operative.
- Fluid management is very important in snake bite cases. Intravenous administration is always the most appropriate route. Blood replacement SHOULD NOT be stared until the circulating venom anticoagulants have been fully neutralized.
- If any signs of Oropharyngeal paralysis or impaired swallowing exist, give NOTHING BY MOUTH, and keep patient on his side with head down. Watch for airway compromise and aspiration.
- Morphine is CONTRAINDICATED because of its tendency to suppress respiration. Alcohol should also be avoided. Diazepam (Valium) may be given, but not in large quantities.
- In cases in which Circulatory Shock remains uncorrected by antivenom therapy, Plasma volume expanders and/or vasopressor agents may be given with appropriate considerations.
- Tetanus prophylaxis should be current.
- Antibiotics are NOT recommended prophylactically.
- Multiple Bites:
- It is possible for a King Cobra 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), twice (2X) the INITIAL dose of antivenom should be given: FOUR vials (12000 units) diluted in Lactated Ringers Solution to a total volume of 240 mls, and delivered over 30 minutes at a rate of 8 mls per minute (i.e., 4 vials per 30 minutes or 400 units per minute).
- Severe Envenomation:
- If the patient shows severe signs of envenomation, particularly if early after the bite, increase the INITIAL dose of antivenom 2X or 3X. Dilute this volume 1:10 in Lactated Ringers Solution, and deliver over 30 minutes. If the patient is in extreme fluid load, antivenom may be delivered at more concentrated volumes until the patient is in appropriate fluid balance.
- 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 King Cobra envenomation are present.
- If there is reason to believe that the patient may be sensitive to equine protein products (e.g., previous snake bite treated with antivenom in which a sensitivity reaction was noted, multiple previous snake bites):
- Administer 1 gram of Solumedrol I.V. push.
- Wait 15 minutes.
- Administer the antivenom at a rate as tolerated by the patient, and beginning at a rate of 3 mls/ minute (i.e., 150 units/min).
- Monitor Pulse and Blood Pressure carefully. Be prepared to treat for Anaphylaxis with Epinephrine and other vasoactive medications.
- Clinical Experience with Ophiophagus hannah:
- The King Cobra is indeed the largest of the world's venomous snakes approaching and perhaps surpassing lengths of 18 feet. Although its venom, drop for drop, is less toxic than those of many of the smaller cobras and other elapids, the volume of venom the King Cobra is capable of producing and delivering in a single bite is enormous. Thus, any aggravated attack with clinical evidence of envenomation may rapidly result in a life-threatening emergency. In nature, the King Cobra feeds almost exclusively on other snakes including the Common Cobra (Naja naja ssp.).
- Although very widely distributed over southern Asia, the King Cobra is not often encountered in nature by humans, and is rarely a cause of snake bite accidents. The few confirmed attacks by King Cobras in nature have often resulted in rapid death. In other cases, dry bites or mild envenomation have been reported.
- Few clinical cases have actually been recorded. In general, a rapidly progressing neurotoxic syndrome develops which includes early respiratory paralysis and loss of consciousness. Delay in administration or insufficient dosages of antivenom may allow such neurological symptoms to manifest which may be very difficult to reverse once established. Large amounts of antivenom have been required to reverse the progression of symptoms in some cases, and recovery may be slow.
The following references are recommended for further indepth reading. This material includes case histories, guidelines and recent findings in elapid literature. These should be read only after treatment has begun, and the patient is in stable status.
- COMMONWEALTH SERUM LABORATORIES: Treatment of Snake Bite in Australia and Papua New Guinea using Antivenom (Package Insert with Antivenom). CSL, June 1982.
- GANTHAVORN, S.: A Case of King Cobra Bite. Toxicon, 9:293, 1971.