UNCONTROLLED WHEN PRINTED
Quick Chart
Introduction
- 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
- Muscle rigidity
- Poor reflexes
- Dilated pupils
- Hypotension
- Bradycardia
- 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.
Management
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 (EMT / Level 2)
- 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 (AP)
- 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 (CCP, PSO)
- Consider MEQU Fluid & Blood Warmer for intravenous fluid replacement.
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
References
References
Document Control
Directorate
Clinical Services
Responsible Manager
Head of Clinical Services
Published Date
Review Date
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