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Family: Viperidae
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Subfamily: Crotalinae
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Genus: Deinagkistrodon
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Species: acutus
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Common Names
Sharp-nosed Pit Viper , Hundred-pacer , Hundred-Pace Pit Viper , Chinese Moccasin
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Local Names
Jian Wen Fu , Pa-po-tuzwa
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Region
Southeast Asia + North Asia
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Countries
China, Laos, Taiwan, Vietnam
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Taxonomy and Biology
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Adult Length: 1.20 m
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General Shape
Very stout thick bodied snake with short tail which ends in a compressed, pointed and curved cornified scale. Can grow to a maximum of about 1.6 metres. Head is large, triangular shaped and distinct from neck with a long and upturned bluntly pointed snout. Eyes are medium in size with vertically elliptical pupils. Dorsal scales are strongly and tubercularly keeled ( tips with 2 tubercules ). Dorsal scale count 21 ( 21 to 23 ) - 21 ( 23 ) - 17 ( 17 to 19 ).
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Habitat
Forested mountains up to an elevation of about 1400 metres. Most common on lower mountain slopes and rocky hill terrain with small valleys.
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Habits
Sluggish and docile snake but it strikes and bites vigorously when provoked. It remains in a coiled strike position facing its aggressor.
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Prey
Feeds mainly on rats, frogs, toads, lizards and birds.
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Venom
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Average Venom Qty
214 mg ( dry weight ), Sawai (1976) ( Ref : R000769 ).
Guangxi : 59 mg ( dry weight ), Gopalakrishnakone and Chou (1990) ( Ref : R000004 ) p259.
Fujian : 176 mg ( dry weight ), Gopalakrishnakone and Chou (1990) ( Ref : R000004 ) p259.
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General: Venom Neurotoxins
Not present
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General: Venom Myotoxins
Not present
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General: Venom Procoagulants
Mixture of procoagulants
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General: Venom Anticoagulants
Possibly present
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General: Venom Haemorrhagins
Probably present
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General: Venom Nephrotoxins
Probably not present
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General: Venom Cardiotoxins
Probably not present
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General: Venom Necrotoxins
Present but not defined
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General: Venom Other
Unknown
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Clinical Effects
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General: Dangerousness
Severe envenoming possible, potentially lethal
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General: Rate of Envenoming: >80%
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General: Untreated Lethality Rate: 1-10%
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General: Local Effects
Marked local effects; pain, severe swelling, bruising, blistering, necrosis
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General: Local Necrosis
Uncommon but can be moderate to severe
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General: General Systemic Effects
Variable non-specific effects which may include headache, nausea, vomiting, abdominal pain, diarrhoea, dizziness, collapse or convulsions
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General: Neurotoxic Paralysis
Does not occur, based on current clinical evidence
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General: Myotoxicity
Does not occur, based on current clinical evidence
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General: Coagulopathy & Haemorrhages
Very common, coagulopathy + haemorrhagins causing bleeding is major clinical effect
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General: Renal Damage
Recognised complication, usually secondary to coagulopathy
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General: Cardiotoxicity
Does not occur, based on current clinical evidence
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General: Other
Shock secondary to fluid shifts due to local tissue injury is likely in severe cases
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First Aid
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Description: First aid for bites by Viperid snakes likely to cause significant local injury at the bite site (see listing in Comments section).
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Details
1. After ensuring the patient and onlookers have moved out of range of further strikes by the snake, the bitten person should be reassured and persuaded to lie down and remain still. Many will be terrified, fearing sudden death and, in this mood, they may behave irrationally or even hysterically. The basis for reassurance is the fact that many venomous bites do not result in envenoming, the relatively slow progression to severe envenoming (hours following elapid bites, days following viper bites) and the effectiveness of modern medical treatment. 2. The bite wound should not be tampered with in any way. Wiping it once with a damp cloth to remove surface venom is unlikely to do much harm (or good) but the wound must not be massaged. 3. All rings or other jewellery on the bitten limb, especially on fingers, should be removed, as they may act as tourniquets if oedema develops. 4. The bitten limb should be immobilised as effectively as possible using an extemporised splint or sling; if available, crepe bandaging of the splinted limb is an effective form of immobilisation. 5. If there is any impairment of vital functions, such as problems with respiration, airway, circulation, heart function, these must be supported as a priority. In particular, for bites causing flaccid paralysis, including respiratory paralysis, both airway and respiration may be impaired, requiring urgent and prolonged treatment, which may include the mouth to mask (mouth to mouth) technique of expired air transfer. Seek urgent medical attention. 6. Do not use Tourniquets, cut, suck or scarify the wound or apply chemicals or electric shock. 7. Avoid peroral intake, absolutely no alcohol. No sedatives outside hospital. If there will be considerable delay before reaching medical aid, measured in several hours to days, then give clear fluids by mouth to prevent dehydration. 8. If the offending snake has been killed it should be brought with the patient for identification (only relevant in areas where there are more than one naturally occurring venomous snake species), but be careful to avoid touching the head, as even a dead snake can envenom. No attempt should be made to pursue the snake into the undergrowth as this will risk further bites. 9. The snakebite victim should be transported as quickly and as passively as possible to the nearest place where they can be seen by a medically-trained person (health station, dispensary, clinic or hospital). The bitten limb must not be exercised as muscular contraction will promote systemic absorption of venom. If no motor vehicle or boat is available, the patient can be carried on a stretcher or hurdle, on the pillion or crossbar of a bicycle or on someone's back. 10. Most traditional, and many of the more recently fashionable, first aid measures are useless and potentially dangerous. These include local cauterization, incision, excision, amputation, suction by mouth, vacuum pump or syringe, combined incision and suction ("venom-ex" apparatus), injection or instillation of compounds such as potassium permanganate, phenol (carbolic soap) and trypsin, application of electric shocks or ice (cryotherapy), use of traditional herbal, folk and other remedies including the ingestion of emetic plant products and parts of the snake, multiple incisions, tattooing and so on.
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Treatment
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Treatment Summary
Bites by hundred pace vipers cause potentially severe local & systemic effects, especially coagulopathy. Urgent assessment, good wound care and IV antivenom are required for treatment.
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Key Diagnostic Features
Local pain, swelling, blistering, necrosis + coagulopathy, bleeding
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General Approach to Management
All cases should be treated as urgent & potentially lethal. Rapid assessment & commencement of treatment including appropriate antivenom (if indicated & available) is mandatory. Admit all cases.
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Antivenom Therapy
Antivenom is the key treatment for systemic envenoming. Multiple doses may be required.
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1. Antivenom Code: SAsSIC03
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Antivenom Name: Purified Agkistrodon acutus Antivenom
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Manufacturer: Shanghai Institute of Biological Products
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Phone: ++86-21-6280-3189
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Address: No. 1262, Yan An Rd. (W) Shanghai 200052
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Country: Peoples Republic of China
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2. Antivenom Code: SAsVCT03
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Antivenom Name: Monovalent Antivenin Snorkel-viper, Agkistrodon antivenin
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Manufacturer: National Institute of Preventative Medicine
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Phone: +886-2-2395-9825
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Address: Linshen Office Address: No.6, Linshen S. Rd., Taipei, Taiwan 100, R.O.C.
Kunyang Office Address: No.161, KunYang St., Taipei, Taiwan 115, R.O.C.
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Country: Taiwan
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