Quick Chart
  • Hypothermia is defined as a core temperature below 35°C
 Clinical Presentation
Mild hypothermia (32-35°C):
  • Decreased respiratory rate
  • Lethargy
  • Weakness
  • Slurred speech
  • Ataxia
  • Shivering may cease
Moderate hypothermia (30-32°C):
  • Muscle rigidity
  • Poor reflexes
  • Dilated pupils
  • Hypotension
  • Bradycardia
Severe hypothermia (< 30°C):
  • Flaccid muscles
  • Fixed pupils
  • Arrhythmias
  • Cardiac arrest
 Exclusion Criteria
Exclusion Criteria
 Risk Assessment
  • Avoid sudden motion, which may trigger ventricular arrhythmia in moderate to severe hypothermia.
  • Controlled hypothermia can play a positive role in managing a patient post cardiac arrest. In this situation hypothermia is used to protect the patient from the detrimental effects of reduced cerebral perfusion (32-34ºC).
  • Immersion hypothermia generally develops more rapidly as well as in patients where thermo-regulation is impaired (the elderly and very young).
  • On the ECG of a hypothermic patient, there are often characteristic Osborne (J) waves. An Osborne wave is a slow, positive deflection at the end of the QRS complex, most prominent in lead II and V3-V6.
Primary Care
  • Primary Survey
    • When safe to do so, remove the patient from the cold environment
    • Position patient recumbent if appropriate or a position of comfort
  • Vital Sign Survey
    • Closely monitor patients temperature and BGL 
  • Consider Oxygen if indicated as per CPG
  • Provide warm oral fluids to drink if fully conscious
  • Remove wet and cold clothing
  • Passively re-warm with blankets and warm surroundings (e.g. in-ambulance/vehicle heater)
Intermediate Care
  • Apply cardiac monitor if trained and authorised
  • Monitor patient persistently, recording full observations every 10 minutes (or 5 minutes if time critical)
  • Transport Priority 1 if patient time critical, pre-notifying receiving facility
Advanced Care
  • Apply cardiac monitoring
  • Consider vascular access
  • Monitor patient persistently, recording full observations every 10 minutes (or 5 minutes if time critical)
  • Transport Priority 1 if patient time critical, pre-notifying receiving facility
Critical & Extended Care
 Additional Information

Cardiac Arrest secondary to Hypothermia:

  • Hypothermia in Western Australia as a cause of cardiac arrest is extremely rare and mostly accidental e.g. locked in a cool room. If you suspect that the cardiac arrest was secondary to hypothermia, the emphasis is on high performance CPR and transport.
  • ASMA available for advice
Key Terms & Links
Extended Care:
Colour assist:


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