Quick Chart
  • Some marine creatures are capable of injecting venom causing paralysis and respiratory failure within 30 minutes. Most venom reaches the blood stream via the lymphatic system. Research by the ARC indicates little venom reaches the circulation, even after several hours, if a Pressure Immobilization Technique is applied IMMEDIATELY and MAINTAINED.
  • Blue-ringed octopuses are present in all Australian coastal waters, often found in tidal pools and can inflict a potentially fatal bite when handled.
  • Cone shells are found in tropical waters, and deliver venom through a dart like barb.
Clinical Presentation
  • Painless bite, spot of blood at the site
  • Numbness to lips and tongue
  • Progressive weakness of respiratory muscles, hypoventilation and respiratory arrest
  • Headache, nausea/vomiting, abdominal pain
  • Swollen or tender lymphatic glands at groin/axilla of bitten limb
  • Symptoms can resemble dysfunction of the CNS:
    • Confusion
    • Collapse
    • Visual disturbances
    • Drooping eyelids
    • Difficulty speaking, swallowing or breathing
    • Weakness/paralysis
    • Respiratory weakness/arrest
    • Seizure         
Exclusion Criteria
Exclusion Criteria
Risk Assessment
  • The amount of toxin administered at the time of envenomation AND the weight of the patient dictates the speed with which life-threatening signs and symptoms may develop.
  • It is advised that such patients be transported to a medical facility for assessment and observation.
  • Venom from both Cone Shell and Blue-ringed Octopus can cause paralysis and respiratory failure within 30 minutes, without direct effects on the heart, the treatment for which is basic life support to assist respiration.
  • Paralysis may be long lasting and where possible treatment for respiratory or cardiac arrest should continue until arrival at an appropriate medical facility.
  • It is uncommon for a patient with an effectively applied PIT to be time critical in the absence of signs and symptoms of envenomation 
Primary Care
  • Primary Survey
  • Keep patient at rest and limit movement where possible
    • Continually reassure
    • Do not:
      • Walk the patient
      • Utilise an artery tourniquet.
      • Apply a Pressure Immobilization Technique if the bite does not occur on a limb.
  • Apply Pressure Immobilization Technique to bitten limb as per clinical skill.
    • If applied correctly, and in a timely fashion, the PIT should slow the progression of venom
  • Apply splint to further minimize movement
  • Conduct Vital Sign Survey, monitoring closely for respiratory depression (assist ventilations as required)
  • DO NOT remove bandages or splint prior to arrival at a suitable hospital for treatment
Intermediate Care (EMT / Level 2)
  • Apply cardiac monitor if trained and authorised
  • Consider pain relief
  • Consider anti-emetic
  • Monitor patient persistently, recording full observations every 10 minutes (or 5 minutes if time critical)
  • Transport Priority 1 if signs and symptoms of envenomation is evident; pre-notify receiving facility
Advanced Care (AP)
Critical & Extended Care (CCP, PSO)
  • As per Advanced Care (AP) guidelines
Additional Information
  • Despite paralysis, the patient may still be able to hear surroundings

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