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Scenario โ€” Hypothermia following prolonged outdoor exposure
Patient Information
Dispatch
You are called to a patient (Ronald Hatch, 75YO male) found seated on a bench outside the main grandstand. Bystanders report he has been sitting in the cold and wind for over two hours and is now difficult to rouse.
Incident History
Pt attended the ANZAC Day dawn service at Langley Park. After the ceremony he sat on a bench and friends were unable to get him to stand up. Pt is lethargic, speaking slowly, and is wet from early morning drizzle. Bystanders unsure how long he has been unresponsive to questions.
Emergency Contact
Margaret Hatch (Wife) 0412 554 871
Response
Voice
Airway
Patent. Nil airway obstruction. Nil stridor. Airway self-maintained at this time.
Breathing
Shallow and slow. Decreased respiratory rate. Mild reduction in chest excursion. Nil audible wheeze or crackle.
Circulation
Weak and slow radial pulse. Skin pale, cold and dry to touch. Nil active bleeding. Peripheral vasoconstriction noted โ€” fingers and lips pale.
Disability
GCS 11 (E3V3M5). Confused and disoriented to time and place. Slurred speech. Responds to voice but does not follow complex commands.
Exposure
Patient is wearing a thin dress shirt and trousers โ€” both visibly wet from rain. No visible trauma. Mild generalised muscle weakness noted on brief assessment. No rash, no wounds.
Vitals
Time SpO2 Resp Dist RR Pulse BP CRT GCS PERL Temp BGL Pain
Initial 93% (RA) Mild 9 46 88/58 4s 11 4 4 SL 31.8 3.6 mmol/L 2
10 mins 96% (O2 NRB 15L) Nil 12 52 96/62 3s 13 4 4 SL 32.4 3.6 mmol/L 1
History Taking
Signs/Symptoms
Lethargy, weakness, slurred speech, confusion, slow to respond. Patient reports feeling 'very cold' and 'heavy'. Mild shivering noted initially โ€” now absent.
Onset
Gradual onset over approximately 2 hours. Friends noticed deterioration in the last 30 minutes.
Pain
Generalised mild aching across limbs โ€” 2/10.
Quality
Diffuse muscle weakness and heaviness. No focal pain.
Radiates
Nil
Severity
2/10
Allergies
Nil known drug allergies.
Medications
Metoprolol (beta-blocker) for atrial fibrillation. Warfarin for anticoagulation. Ramipril for hypertension.
Pertinent History
Known atrial fibrillation. Hypertension. No history of diabetes. Lives independently with wife. Walked approximately 1.5km to the event this morning. Has been seated outside in wind and drizzle since the ceremony ended approximately 2 hours ago.
Last Oral Intake
Cup of tea approximately 3 hours ago. Nil food since previous evening.
Treatment
Friends placed a jacket over his shoulders approximately 20 minutes ago. No medications administered.
Events Leading
Patient attended the ANZAC Day dawn service. After the formal ceremony concluded he sat alone on a park bench while friends attended an indoor function. Friends returned to find him drowsy and difficult to rouse.
Scenario Progression and Treatment Objectives

((If trainees do not remove wet clothing promptly โ€” after 3 minutes the patient begins shivering violently then abruptly stops, and GCS drops to 9. Facilitator states: 'The patient is no longer responding to your voice.'))

((If oxygen is not applied within 3 minutes โ€” SpO2 drops to 90% on room air and respiratory rate falls to 7. Facilitator states: 'The patient's breathing is becoming more shallow.'))

((If BGL is not checked โ€” facilitator prompts at 5 minutes: 'The patient seems to be getting more confused โ€” is there anything else you want to check?'))

((If trainees attempt to mobilise the patient rapidly or handle roughly โ€” facilitator states: 'As you move him briskly the patient suddenly becomes unresponsive and pulseless.' Manage as cardiac arrest secondary to hypothermia. Emphasise that sudden motion can trigger ventricular arrhythmia in moderate-to-severe hypothermia.))

((If warm oral fluids are offered without confirming GCS is 15 โ€” facilitator states: 'The patient reaches for the cup but cannot grip it and his head slumps forward.' Remind trainees warm oral fluids are only appropriate if the patient is fully conscious.))

This patient is suffering from moderate hypothermia (estimated core temperature 30โ€“32ยฐC) with associated bradycardia, hypotension, reduced GCS, and absent shivering โ€” consistent with his prolonged cold and wet exposure. His beta-blocker (metoprolol) blunts the normal compensatory tachycardia, and warfarin use is a relevant background factor requiring documentation for the receiving facility.

  • Ensure scene safety and don appropriate PPE.
  • Perform Primary Survey โ€” establish patient is responsive to voice, airway self-maintained, breathing shallow and slow, pulse weak and bradycardic.
  • Move patient to a sheltered environment (inside FAP or ambulance) โ€” remove from wind and cold immediately.
  • Handle patient gently throughout โ€” avoid sudden or rough movement to reduce risk of precipitating ventricular arrhythmia.
  • Remove all wet clothing carefully โ€” dress shirt and trousers are wet and must be removed.
  • Apply oxygen via non-rebreather mask at 10โ€“15 L/min targeting SpO2 94โ€“98%.
  • Perform Vital Sign Survey โ€” obtain GCS, SpO2, RR, BP, HR, CRT, BGL, and tympanic temperature.
  • Record tympanic temperature โ€” note this may underestimate true core temperature in extreme cold environments; document and interpret in conjunction with clinical presentation.
  • Check BGL โ€” result 3.6 mmol/L. Patient is at low threshold; monitor closely but does not meet criteria for glucose gel at this time (threshold <4 mmol/L with altered conscious state; BGL is borderline โ€” reassess at 10 minutes).
  • Passively rewarm patient โ€” wrap in Ready-Heat blanket (place sheet between blanket and skin first), then cover with standard blanket. Apply additional blankets as available.
  • Do NOT offer warm oral fluids โ€” patient GCS is 11/15, therefore oral intake is unsafe.
  • Record full observations every 10 minutes.
  • Note medications: metoprolol (beta-blocker) will blunt compensatory tachycardia โ€” low HR may underestimate severity; warfarin โ€” relevant for receiving facility documentation.
  • Reassess GCS, SpO2, HR and temperature at 10 minutes โ€” expect gradual improvement with passive rewarming and oxygen.
  • Arrange transport โ€” Priority 1 given GCS <15, bradycardia, hypotension, and moderate hypothermia. Pre-notify receiving ED.
  • Continue monitoring during transport โ€” be alert for deterioration in GCS or cardiac rhythm changes (bradyarrhythmias are common in moderate hypothermia).
  • Prepare resuscitation equipment โ€” defibrillator and BVM at hand in the event of cardiac arrest secondary to hypothermia.
  • Scenario ends on arrival of ambulance and IMISTAMBO handover.
  • Attention to hand hygiene will be given throughout the scenario.

Clinical references: Hypothermia ยท Oxygen Delivery ยท Blood Glucose Monitor ยท Tympanic Thermometer ยท Ready Heat Blanket ยท Primary Survey ยท Unconsciousness