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![Pseudechis australis ( Mulga Snake ) [ Original photo copyright © Dr Julian White ]](images/snakes/SNP05211.jpg)
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Family: Elapidae
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Subfamily: Elapinae
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Genus: Pseudechis
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Species: australis
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Common Names
Mulga Snake , King Brown Snake
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Region
Australia
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Countries
Australia
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Taxonomy and Biology
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Adult Length: 2.00 m
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General Shape
Large in length, moderately slender and moderately robust snake with a medium length tail. Can reach a maximum total length of over 2.70 metres. Head is broad, with a rounded snout, somewhat bulbous cheeks in large specimens and barely distinct from robust neck. The brow ridge is medium to long. Eyes are medium in size with round pupils. Head and body scales are semi-glossy to glossy.
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Habitat
Found in almost all Australian mainland habitats from the wettest tropical forests to the driest interior deserts. Does not inhabit swamps, alpine regions, the cooler southern fringes, Tasmania or the wetter southeastern coast, slopes, plains and ranges of Australia. Found in savanna and savanna woodlands of New Guinea.
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Habits
Mainly a diurnal and terrestrial forager in cooler weather and southern portions of its range and crepuscular or nocturnal in hotter weather and northern portions of its range. Shelters in abandoned animal burrows, deep soil cracks, under logs, under large rocks, in rock cavities and crevices. Disposition seems to vary by region. Southern specimens tend to be quite shy and only bite if provoked, whereas some northern specimens are quite excitable and may bite if approached.
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Prey
Feeds on a diverse range of prey including many lizard species ( particularly skinks and agamids ), snakes, small mammals ( particularly mice ), frogs, birds and eggs.
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Venom
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Average Venom Qty
180 mg ( dry weight of milked venom ), Meier and White (1995) ( Ref : R000001 ).
150 to 300 mg ( dry weight ), Minton (1974) ( Ref : R000504 ).
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Preferred LD50 Estimate
2.38 mg / kg sc ( mice ), Meier and White (1995) ( Ref : R000001 )
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General: Venom Neurotoxins
Possibly present but not clinically significant
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General: Venom Myotoxins
Systemic myotoxins present
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General: Venom Procoagulants
Not present
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General: Venom Anticoagulants
Direct coagulation inhibitor
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General: Venom Haemorrhagins
Not present
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General: Venom Nephrotoxins
Secondary nephrotoxicity only
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General: Venom Cardiotoxins
Not present
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General: Venom Necrotoxins
Not present
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General: Venom Other
Not present or not significant
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Clinical Effects
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General: Dangerousness
Severe envenoming likely, high lethality potential
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General: Rate of Envenoming: 40-60%
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General: Untreated Lethality Rate: 30-40%
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General: Local Effects
Local pain, swelling & bruising
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General: Local Necrosis
Rarely occurs, minor only
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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
Rarely reported, usually minor
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General: Myotoxicity
Very common, major clinical effect, usually moderate to severe
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General: Coagulopathy & Haemorrhages
Uncommon to rare, but may be moderate to severe coagulopathy
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General: Renal Damage
Recognised complication, usually secondary to myolysis
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General: Cardiotoxicity
Uncommon, secondary to myolysis-induced hyperkalaemia
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General: Other
Not likely to occur
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First Aid
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Description: First aid for bites by Elapid snakes which do not cause significant injury at the bite site (see Comments for partial listing), but which may have the potential to cause significant general (systemic) effects, such as paralysis, muscle damage, or bleeding.
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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. For Australian snakes only, do not wash or clean the wound in any way, as this may interfere with later venom detection once in a hospital.
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. If the bite is on a limb, a broad bandage (even torn strips of clothing or pantyhose) should be applied over the bitten area at moderate pressure (as for a sprain; not so tight circulation is impaired), then extended to cover as much of the bitten limb as possible, including fingers or toes, going over the top of clothing rather than risking excessive limb movement by removing clothing. The bitten limb should then be immobilised as effectively as possible using an extemporised splint or sling.
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
Mulga snake bites have a high potential for major envenoming and require urgent assessment. For all cases with significant systemic effects (especially myolysis, anticoagulant coagulopathy) give antivenom.
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Key Diagnostic Features
Local pain & swelling + myolysis ± anticoagulant coagulopathy ± renal failure
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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: SAuCSL09
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Antivenom Name: Black Snake Antivenom
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Manufacturer: CSL Limited
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Phone: ++61-3-9389-1911
Toll free: 1800 642 865
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Address: 45 Poplar Road
Parkville
Victoria 3052
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Country: Australia
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| 2. Antivenom Code: SAuCSL12
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Antivenom Name: Polyvalent Snake Antivenom ( Australia - New Guinea )
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Manufacturer: CSL Limited
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Phone: ++61-3-9389-1911
Toll free: 1800 642 865
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Address: 45 Poplar Road
Parkville
Victoria 3052
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Country: Australia
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