What are the management strategies for hypothermia?

Management Strategies for Hypothermia

Hypothermia management requires a staged approach based on severity, with immediate removal from cold environments, removal of wet clothing, and application of both passive and active rewarming techniques appropriate to the degree of hypothermia. 1, 2

Classification and Assessment

Hypothermia is classified based on core temperature and clinical presentation:

Severity Level	Temperature	Clinical Signs
Cold stress	35-37°C	Alert, possibly shivering
Mild	32-35°C	Altered mental status, shivering
Moderate	28-32°C	Decreased responsiveness, ±shivering
Severe/profound	<28°C	Unresponsive, appears lifeless, slow heart rate/breathing, high risk for arrhythmias

Management Algorithm

Step 1: Initial Management (All Patients)

• Move patient from cold to warm environment
• Remove wet clothing
• Protect from further heat loss with dry insulation
• Cover head and neck
• Insulate from ground
• Shield from wind using plastic or foil layer
• Monitor core temperature regularly 1, 2

Step 2: Rewarming Based on Severity

For Cold Stress (35-37°C):

• Passive rewarming (blankets, warm environment)
• Monitor temperature every 15 minutes
• Usually adequate in healthy people 1, 2

For Mild Hypothermia (32-35°C):

• Passive rewarming plus active external warming
• Apply warming blankets
• Consider forced warm air systems
• Protect from falls (altered mental status)
• Monitor temperature every 5-15 minutes
• Consider high-calorie foods/drinks if alert 1, 2

For Moderate Hypothermia (28-32°C):

• Medical emergency requiring all available warming methods
• Activate emergency response system
• Handle patient gently to prevent arrhythmias
• Use active external warming (warming blankets, forced air)
• Consider active core rewarming methods
• Monitor temperature continuously 1, 2

For Severe/Profound Hypothermia (<28°C):

• Critical emergency requiring immediate intervention
• Activate emergency response system
• Handle extremely gently (high risk for arrhythmias)
• Implement active core rewarming techniques:
  • Warmed IV fluid infusions
  • Heated humidified oxygen
  • Body cavity lavage
  • Extracorporeal blood warming (ECMO)
• Continuous cardiac monitoring 1, 2

Special Considerations

Cardiac Arrest with Hypothermia

• Continue CPR
• Limit defibrillation attempts until core temperature >30°C
• Consider ECMO for severe cases
• Prolonged resuscitation may be necessary 1, 2

Safety Precautions for Rewarming

• Place insulation between heat sources and skin
• Follow manufacturer instructions for warming devices
• Monitor frequently for pressure injuries and burns
• Continue warming until core temperature reaches 36°C
• Stop rewarming after reaching 37°C to avoid overheating 1, 2

Rewarming Rate

• Slow rewarming is recommended at 0.25-0.5°C per hour
• Rapid rewarming can cause electrolyte shifts and hemodynamic instability
• Rebound hyperthermia is associated with worse outcomes 1

Physiological Effects and Complications

Hypothermia affects multiple body systems:

• Cardiovascular: Bradycardia, arrhythmias, decreased cardiac output (severe)
• Respiratory: Decreased respiratory rate, increased secretions, atelectasis
• Hematological: Impaired coagulation (especially <33°C), platelet dysfunction
• Metabolic: Cold-induced diuresis, electrolyte abnormalities
• Neurological: Altered mental status progressing to unconsciousness 1

Managing Complications

• Monitor for coagulopathy in trauma patients (synergistic effect with acidosis)
• Address electrolyte abnormalities (hypophosphataemia, hypokalaemia, hypomagnesaemia)
• Watch for shivering (increases metabolic demand)
• Consider sedation protocols for moderate-severe cases 1

Pitfalls to Avoid

• Rough handling of moderately to severely hypothermic patients (can trigger arrhythmias)
• Neglecting to monitor core temperature continuously in moderate-severe cases
• Rewarming too quickly (aim for 0.25-0.5°C/hour)
• Failing to recognize hypothermia in trauma patients (part of "trauma triad of death")
• Stopping treatment before reaching normothermia (36°C) 1, 2

Hypothermia is responsible for approximately 1300 deaths annually in the United States, with highest rates among men, elderly, and rural populations. With proper recognition and staged management according to severity, outcomes can be significantly improved 1, 2.