What is the treatment for hypothermia (low body temperature)?

Treatment of Hypothermia

Remove the patient from the cold environment immediately, strip off all wet clothing, and initiate both passive rewarming with dry blankets and active rewarming measures simultaneously—the severity of hypothermia dictates the aggressiveness of intervention, with mild cases responding to passive measures while moderate-to-severe cases require active external and core rewarming techniques. 1

Immediate Initial Actions (All Severity Levels)

• Move the patient to a warm environment and remove all wet, cold clothing to prevent further heat loss 1
• Insulate from the ground and cover the head and neck, as significant heat loss occurs through these areas 1
• Shield from wind using a plastic or foil layer in addition to dry insulating layers 1
• Handle the patient gently throughout treatment to avoid triggering ventricular fibrillation, particularly in moderate-to-severe cases 1, 2

Severity-Based Treatment Algorithm

Mild Hypothermia (32-35°C / 89.6-95°F)

Clinical presentation: Altered responsiveness with shivering 1

• Passive rewarming with blankets is often adequate for healthy individuals 1, 3
• Active external rewarming may be added using forced-air warming blankets (e.g., Bair Hugger) 2, 3
• Provide high-calorie foods or warm drinks if the patient is alert and able to swallow 3
• Monitor for deterioration and protect from falls due to altered mental status 1, 3

Moderate Hypothermia (28-32°C / 82.4-89.6°F)

Clinical presentation: Decreased responsiveness (responds only to loud voice or pain), shivering may be absent 1

• This is a medical emergency—activate the emergency response system immediately 1
• Apply forced-air warming blankets as the primary active external rewarming method 2, 3
• Administer warmed intravenous fluids at 40-45°C (isotonic crystalloid: normal saline or Ringer's lactate) in volumes of 500 mL to 30 mL/kg 4
• Provide humidified, warmed oxygen to support respiratory function and minimize heat loss 2, 3
• Use all available passive and active rewarming methods in tandem 1

Severe Hypothermia (<28°C / <82.4°F)

Clinical presentation: Unresponsive, may appear lifeless, slow heart rate and breathing, high risk for cardiac arrest 1

• Full resuscitative measures are mandatory unless there are signs of obvious death (rigor mortis, nonsurvivable traumatic injury) 1
• Continue all measures for moderate hypothermia plus consider active core rewarming techniques 3
• Active core rewarming options include:
  • Warmed IV fluids at 40-45°C 1, 4
  • Warm humidified oxygen 1, 2
  • Intrathoracic or intraperitoneal warm-water lavage 1
  • Extracorporeal rewarming (ECMO) when available for the most severe cases 1
• Do not consider the patient dead before rewarming unless obvious signs of death are present 1

Temperature Monitoring

• Use esophageal thermometer, bladder catheter (in non-anuric patients), or pulmonary artery catheter for accurate core temperature measurement 4
• Avoid axillary measurements as they consistently read 1.5-1.9°C below actual core temperature 3
• Monitor core temperature every 5 minutes during active rewarming to assess progress 2, 4

Rewarming Targets and Endpoints

• Target a minimum core temperature of 36°C before considering the patient stable 2, 3
• Cease rewarming at 37°C as temperatures above this threshold are associated with poor outcomes and increased mortality 2, 3, 4

Critical Complications to Monitor

• Cardiac arrhythmias (particularly ventricular fibrillation) can be triggered by rough handling or rapid rewarming 2, 4
• Coagulopathy develops as hypothermia impairs platelet and coagulation factor function 1, 2
• Rewarming shock may occur as peripheral vasodilation causes relative hypovolemia 3
• Burns and pressure injuries from improper use of heating devices—always place insulation between heat source and skin 1, 3

Important Caveats

Warmed IV fluids alone primarily prevent further heat loss rather than achieve true rewarming—they must be combined with other active rewarming methods and should not be relied upon as the sole intervention 4, 5. True rewarming with IV fluids alone would require prohibitively large volumes (>10 L) 5.

If cardiac arrest occurs during hypothermia, perform defibrillation and administer epinephrine according to standard BLS/ACLS algorithms concurrent with aggressive rewarming strategies 1. Resuscitation efforts should continue until the patient is rewarmed, as severe hypothermia can mimic death 1.

Prevention is crucial—early organized prehospital hypothermia protocols can reduce incidence from 19% to 3% 4.