Snake envenomation

Question 1

Coagulopathy

Answer 1

Clinical:
bleeding gums
bite site
venepuncture
hematemesis
PR bleeding
ICH

Question 2

Venom Induced Consumptive coagulopathy (VICC)

Answer 2

Ix:
- Fibrinogen= 0
- FDP= raised
- D-Dimer= raised
Snakes: tiger, taipan, brown

Question 3

Anticoagulant coagulopathy

Answer 3

Ix:
-INR= raised
- APTT= raised
- Fibrinogen= normal
-FDP= normal
Snakes: mulga (black), red bellied black snake, collet snake

Question 4

Neurotoxicity

Answer 4

Clinical:

• ptosis
• double vision
• blurry vision
• drooling
• bulbar palsy
• generalized weakness
• Resp Decreased PEFR

Question 5

Pre- Synaptic

Answer 5

doesn’t respond to anti venom

Snakes: tiger, taipan, brown, sea snake

Question 6

Post Synaptic

Answer 6

Responds to antivenom

Snakes: death Adders

Question 7

Myotoxicity

Answer 7

Clinical:

• local/ general muscle pain
• tenderness & weakness
• myoglobinuria
• Rhabdomyolysis/ ARF

Snakes: tiger, black, taipan, sea snake

Question 8

Renal Damage:

Answer 8

Rhabdomyolysis- from myotoxicity

Micro angiopathic hemolytic anemia (MAHA)

• ARF
• Severe low platelets
• Anaemia

Question 9

Assessment: Symtoms

Answer 9

Systemic

• N&V
• diarrhea
• abdominal pain
• Diaphoresis
• muscle aches
• headache
• Severe: collapse/ shock
• LOC
• apnea
• cardiac arrest
• Multiorgan failure

Local
-bite site bleeding/ pain/ necrosis

Question 10

Investigations

Answer 10

Bed side:
-ECG: cardiotoxicity
- BSL if ALOC
- VBG: lactic acidosis in shock
-U/A: myoglobinuria, hematuria
-Whole Blood Clotting time (WBCT) >10 min
Lab
- FBE + Film: hemolysis, low Plts
- UEC: K & Creat high in ARF
- CMP: Decreased Ca in Rhabdo
- CK: high in rhabdomyolysis
- Coags: INR, Fibrinogen, FDP, D-Dimer, APTT
- G+H + x-match
- LFTs
-LDH: DIC raised
Imaging: as clinically indicated
SVDK: if clinical & lab signs envenomation aids narrow anti venom choice

Question 11

Envenomation Management

Answer 11

Pre hospital

• PIB
• immobilize limb + patient
• t/f - dr willing to Rx/ Lab can test/ antivenom available

Hospital
-Resus
- IVC
- if envenomed: 1:10 N/saline over 15 min. Stat if cardiac arrest
- Remove PIB at 1 hr if no envenomation
- Reassess clinical + labs 1, 6, 12 hr
Complication:
-shock/ hemorrhage
- respiratory paralysis: ventilation
- Renal failure: IDC, Fluids, Dialysis
- MAHA/ Rhabdomyolysis
- Anaphylaxis
- Serum sickness- delayed 4-21/7 post