Envenomation

Question 1

Length of time to monitor snakebites (if no evidence of envenomation)

Answer 1

12 hours

Question 2

Length of time to monitor funnel web spider bite

Answer 2

4 hours
Neuro-excitatory, pulmonary oedema, catecholamine storm
Immobilise + pressure bandage + AV

Question 3

Length of time to monitor red back spider bite

Answer 3

Only if symptomatic (pain, sweating, HTN, nausea, vomiting, headache) - give AV

Question 4

How long does it take for life-threatening envenomation in marine creatures?

Answer 4

within 1 hour usually, ALWAYS within 4 hours
exception: stingray wounds to the trunk

Question 5

Brown snake coagulopathy

Answer 5

venom-induced consumptive coagulopathy (abnormal INR, fibrinogen very low, d dimer high); cardiac arrest common

Question 6

Tiger snake coagulopathy

Answer 6

venom-induced consumptive coagulopathy (abnormal INR, fibrinogen very low, d dimer high); common to have systemic symptoms

Question 7

Red-bellied black snake coagulopathy

Answer 7

Anticoagulant = APTT 1.5–2.5 x normal ± minor elevation INR. D-dimer and fibrinogen usually normal; common to have systemic symptoms

Question 8

Indications for immediate anti-venom

Answer 8

i. Any evidence of neurotoxic paralysis – ptosis, ophthalmoplegia, limb weakness, respiratory effects
ii. Significant coagulopathy – unclottable blood, INR >1.3, or prolonged bleeding from wounds and venipuncture
iii. History of unconsciousness, collapse, convulsion or cardiac arrest

Give 1 vial of brown and 1 vial of tiger AV