Differential Diagnosis of snake bites ?

DIFFERENTIAL DIAGNOSIS OF VENOMOUS SNAKEBITE
■ non-venomous snakebite
■ bite or sting by other venomous creature
(arthropod, including spider, octopus, jellyfish)
■ CVA
■ ascending neuropathy, eg Guillain-Barre
syndrome
■ AMI
■ allergic reaction
■ hypoglycaemia/hyperglycaemia
■ drug overdose
■ closed head injury
The combination of neurological disturbance and
evidence of defibrination in a patient with an
appropriate history is strongly suggestive of severe
envenomation.

Snake Bites Australia How to investigate

In managing the patient with suspected
snakebite, it is necessary to
establish whether significant envenomation
has occurred and to attempt
to identify the type of snake
involved. A significant proportion of
venomous snakebites don’t result in
envenomation. The use of antivenom
should be reserved for those cases
with clinical or pathologic evidence
of envenomation.

1.Snake venom Detection Kit

2.Clotting Studies

3.Creatinine Kinase-Indicating Myolysis

4.Urinalysis-Haemoglobin,Myoglobin

5.Renal Function-May be impaired secondary to Myoglobinuria or other mechanism.

Austrlian Snake Bites Overview

Effects of Australian snake bite venom are usually
species specific, but in general include:

■ neurotoxins
■ procoagulants
■ anti-coagulants
■ rhabdomyolysins
■ haemolysins (weak).

Presentation



Symptoms and signs of
envenomation may include:
■ EARLY (within 30 minutes)
- headache, nausea/vomiting,
abdominal pain
- coagulopathy
■ LATE (within several hours)
- cranial nerve palsies
(ptosis, ophthalmoplegia,
dysarthria, dysphonia,
dysphagia)
- limb and truncal weakness
- respiratory failure
- haemorrhage
■ VERY LATE (delayed
presentation,
wrong/inadequate treatment)
- prolonged paralysis
- renal failure
- uncontrollable haemorrhage
Features suggestive of snakebite
Identification of snakes is often
unreliable: polyvalent antivenom
should be used if the
type of snake cannot be identified
in all areas of Australia
apart from Tasmania, where
both tiger snake and copperhead
bite may be successfully
treated with tiger snake
antivenom, and Victoria, where
bites should be treated with
combined tiger/brown snake
antivenom


How to treat

Identification of snakes is often
unreliable: polyvalent antivenom
should be used if the
type of snake cannot be identified
in all areas of Australia
apart from Tasmania, where
both tiger snake and copperhead
bite may be successfully
treated with tiger snake
antivenom, and Victoria, where
bites should be treated with
combined tiger/brown snake
antivenom.



Important to remember

■ Correct diagnosis of snakebite
may be delayed because the
bite may not be dramatic or
painful, and snake venom
generally causes little local
pain or tissue destruction.
■ Identification of snakes is often
unreliable: polyvalent
antivenom should be used if
the type of snake cannot be
identified in all areas of
Australia apart from Tasmania,
where both tiger snake and
copperhead bite may be
successfully treated with tiger
snake antivenom.
■ Children are more likely to
sustain multiple bites and may
be more quickly and severely
affected by snakebite than
adults because of their lower
body weight.
■ The combination of
neurological disturbance and
evidence of defibrination in a
patient with an appropriate
history is strongly suggestive of
Severe envenomation

BRONCHOSCOPY

The therapeutic indications for bronchoscopy include:


removal of secretions and mucus plugs:
often used in ITU
pneumonic lobar collapse
allergic bronchopulmonary aspergillosis

removal of foreign bodies

stent insertion in benign airways disease:
for example in relapsing polychondritis

BRONCHOSCOPY

Diagnostic role of flexible bronchoscopy






lung cancer:
the type and operability of lung tumours can be assessed

pneumonia:
good for identifying infecting organism

interstitial lung disease:
permits histoloy and analysis of bronchoalveolar lavage

causes of haemoptysis, cough and recurrent pneumonia