Toxicology Intermediate
Snakebite at outdoor festival
Adult · 28yr · male
Patient Information
- Dispatch
- You are called to a patient (Marcus Hallett, 28YO male) who is sitting on the ground near the back fence of the Vineyard Music Festival grounds reporting he was bitten on the right ankle by a snake approximately 20 minutes ago.
- Patient
- Marcus Hallett — 28yr (80kg)
- Incident History
- Pt was walking through a grassed area behind the festival stage to retrieve a hat when he felt a sharp sting on his right ankle. Bystanders report seeing a brown snake near the fence line. Pt walked back to a nearby seating area and called for help. Pt has not received any first aid.
- Emergency Contact
- Claire Hallett (Wife) — 0412 553 089
Initial Rapid Assessment
- Response
- Alert
- Airway
- Patent. Nil airway obstruction. Nil stridor or swelling.
- Breathing
- Self-ventilating. Slightly elevated respiratory rate. Nil wheeze or crackles. Able to speak in full sentences.
- Circulation
- Radial pulse present, regular, adequate volume. Skin warm and dry. Nil active bleeding. Two small puncture marks visible on right ankle with localised redness.
- Disability
- GCS 15 (E4V5M6). Orientated to time, place and person. Reports mild headache developing. Pupils equal and reactive to light.
- Exposure
- Two small puncture marks noted on right ankle approximately 1cm apart. Mild localised redness. No bandage applied. No other injuries identified.
Vitals
| Time | SpO2 | Resp Dist | RR | Pulse | BP | CRT | GCS | PERL | Temp | BGL | Pain |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Initial | 97% (RA) | Nil | 18 | 96 | 118/74 | <2s | 15 | 4 4 ++ | 36.8 | – | 4 |
| 10 mins | 96% (RA) | Mild | 20 | 104 | 112/70 | <2s | 14 | 4 4 ++ | 36.8 | – | 5 |
History Taking
- Signs/Symptoms
- Sharp pain at bite site on right ankle, mild headache developing, feeling mildly nauseated. Reports tingling sensation beginning in the right leg.
- Allergies
- Nil known drug allergies.
- Medications
- Nil regular medications.
- Pertinent History
- Nil significant past medical history. Non-smoker. Occasional alcohol. Fit and well.
- Last Oral Intake
- Meal and two beers approximately 2 hours ago.
- Events Leading
- Pt was attending the Vineyard Music Festival and walked through a grassed area behind the main stage to retrieve a hat that had blown away. Felt a sharp bite on his right ankle and looked down to see a brown snake moving away.
- Treatment Prior
- Nil. Pt walked back to seating area unassisted. No bandage or first aid applied.
- Onset
- Approximately 20 minutes prior to EHS arrival. Pt was walking in a grassed area when bitten.
- Pain
- Sharp localised pain at bite site right ankle 4/10. Mild headache 2/10.
- Quality
- Sharp, stinging pain at bite site. Dull aching headache.
- Radiates
- Tingling sensation radiating from bite site up the right leg.
- Severity
- 4/10 bite site pain
Treatment Response
Diagnosis
This patient is suffering from a suspected snakebite with early signs of envenomation — presenting with bite site pain, developing headache, nausea, and tingling/paraesthesia ascending the bitten limb approximately 20 minutes post-bite.
Facilitator Triggers — if trainees miss a critical step
- ! (If the trainee allows the patient to walk or stand and mobilise at any point — patient immediately complains of worsening headache, nausea, and begins to vomit. Reinforce: DO NOT walk the patient.)
- ! (If the trainee does not apply Pressure Immobilization Technique within 5 minutes — at the 10-minute mark, patient reports the tingling sensation has spread to the groin and he is feeling increasingly drowsy. GCS drops to 13.)
- ! (If the trainee attempts to apply a CAT tourniquet instead of a PIT bandage — facilitator states 'The patient grimaces and says that feels very tight — it's cutting off circulation.' Prompt the trainee to reconsider and use the correct technique.)
- ! (If the trainee attempts to wash, cut, or suck the bite site — facilitator states 'You move toward the wound' and provides a verbal prompt: 'Is that the correct approach for snakebite first aid?')
- ! (If the trainee does not splint the limb after PIT application — patient shifts position and bends knee, facilitator prompts: 'The patient is moving his leg to get comfortable — what else can you do to minimise movement?')
- ! (If the trainee removes the PIT bandage before hospital handover — facilitator states 'The patient says the bandage feels tight — do you remove it?' Correct answer: No. DO NOT remove prior to arrival at hospital unless authorised by ASMA.)
Treatment Objectives
- 1 Ensure scene safety — confirm snake is no longer present in the immediate area before approaching patient.
- 2 Perform Primary Survey — Airway, Breathing, Circulation, Disability, Exposure.
- 3 Instruct patient to remain STILL — do not allow patient to walk or stand at any point during assessment or treatment.
- 4 Conduct Vital Sign Survey — GCS, SpO2, RR, BP, HR, CRT, pupils, temperature.
- 5 Perform Secondary/CNS Survey — assess bite site on right ankle, note puncture marks, assess for signs of envenomation including nausea, headache, tingling, visual disturbances, weakness, or drooling.
- 6 Apply Pressure Immobilization Technique (PIT) to the right lower limb — commence bandaging from the toes and extend upward as far as possible covering the entire limb, using a snakebite bandage with continuous indicator tensioned to achieve 1.5cm x 1.5cm squares. Firm compression — unable to easily slide a finger beneath bandage.
- 7 Mark the bite site location clearly on the outside of the PIT bandage with a marker.
- 8 Splint the right lower limb to further minimise movement — immobilise in position of comfort.
- 9 Administer oxygen via appropriate mask — titrate to maintain SpO2 94–98%. Apply nasal cannula at 1–4 L/min or simple face mask at 5–8 L/min as clinically indicated. Confirm 6 medication rights: right patient, right drug, right dose, right route, right time, right documentation.
- 10 Monitor patient persistently — record full observations every 10 minutes, monitoring closely for signs of respiratory depression, increasing weakness, descending eyelids, difficulty speaking or swallowing, altered GCS.
- 11 Do NOT remove PIT bandage or splint prior to arrival at hospital.
- 12 Do NOT attempt to catch, kill, or identify the snake.
- 13 Reassure patient continuously — explain procedures calmly and advise he must remain still.
- 14 Arrange urgent ambulance support via CSP — IMISTAMBO handover to CSP — state suspected snakebite with early signs of envenomation, PIT applied, vital signs.
- 15 Scenario ends on arrival of ambulance and IMISTAMBO handover.
- 16 Attention to hand hygiene will be given throughout the scenario.
Clinical references: Snakebite · Pressure Immobilisation Technique (P.I.T) · Primary Survey · Pulse Oximetry · Oxygen Delivery · Secondary & CNS Survey
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