Field Skills

Build a Burrito Hypothermia Wrap

Building a 'burrito wrap' for hypothermia involves creating a multi-layered insulation and vapor barrier system around a non-ambulatory patient to prevent further heat loss and encourage rewarming. This technique is crucial in wilderness medicine for stabilizing someone who cannot generate enough body heat to maintain core temperature. By carefully layering protective materials like tarps and sleeping bags, you create an environment that traps radiated heat while blocking wind and moisture, critical for preventing the body's internal temperature from dropping to dangerous levels. The goal is to stabilize the patient's condition until professional medical help or evacuation is possible, making it a fundamental skill for remote emergencies.

Field Skills 10 min practice Intermediate Cold, wet, or windy wilderness conditions, remote settings, emergency shelters, during patient transport.

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Topic summary

Key takeaways

Patient stops shivering.
Patient reports feeling warmer.
Skin to the touch feels warmer.
Improved mental status (if previously impaired).
Avoid: Not using a ground barrier, allowing conductive heat loss.
Avoid: Leaving gaps in insulation, which allows warm air to escape.

Intended uses

Field Skills skill (Intermediate, ~10 min practice)
Requires: Two sleeping bags, Large waterproof tarp, Survival blanket or smaller tarp

Climate suitability

Cold, wet, or windy wilderness conditions, remote settings, emergency shelters, during patient transport.

Verification notes

Author: Wild10 Editors. Last updated October 14, 2026.

Safety: Always treat hypothermic patients gently. Avoid rubbing or massaging cold extremities, as this can force cold, acidic blood into the core, potentially triggering cardiac arrest. Monitor their breathing and consciousness closely throughout the process.

Required tools

Two sleeping bags
Large waterproof tarp
Survival blanket or smaller tarp

Step-by-step

Lay out a large waterproof tarp or shelter half as the outermost layer, ensuring it is flat.
Why: The outermost layer provides essential protection from ground moisture and wind.
Place a second, slightly smaller vapor barrier (like a survival blanket or another tarp) on top of the first, shiny side towards the patient if reflective.
Why: This layer prevents convective and evaporative heat loss from the patient's body.
Center two open sleeping bags on the vapor barriers, stacked or nested, with zippers aligned if possible.
Why: Multiple sleeping bags provide critical loft and insulation to trap radiated heat.
Carefully transfer the patient onto the center of the innermost sleeping bag, ensuring their head is clear.
Why: Proper positioning ensures effective wrapping and avoids unnecessary patient movement.
Zip up or securely wrap the innermost sleeping bag around the patient, covering as much skin as possible.
Why: Sealing the inner sleeping bag maximizes insulation contact and prevents heat escape.
Fold and secure the outer sleeping bag around the first, tucking in gaps to create a second insulating layer.
Why: Adding a second insulation layer significantly boosts thermal retention.
Wrap the vapor barriers tightly around the entire assembly, tucking excess material underneath to seal the 'burrito'.
Why: A tight outer wrap seals the system against the elements and keeps internal layers in place.

Tip: Place warm water bottles (sealed, non-leaking) or chemical heat packs strategically inside the inner sleeping bag near major arteries like the neck, armpits, and groin to aid rewarming.

Common mistakes

Not using a ground barrier, allowing conductive heat loss.
Leaving gaps in insulation, which allows warm air to escape.
Failing to use a vapor barrier, leading to evaporative heat loss.
Over-compressing insulation, reducing its effectiveness.
Moving the patient unnecessarily, which can worsen their condition.

Troubleshooting

If patient is still shivering, add more insulation or hot water bottles inside the wrap.
If the patient feels damp, ensure the vapor barrier is properly sealed and add absorbent material if possible.
If the wrap feels loose, re-cinch layers or add more material to fill voids.
If wind penetrates, reinforce the outer tarp with natural windbreaks or additional layers.

Field practice drill

Practice this wrap with a partner or large dummy until it can be completed in under ten minutes, focusing on smooth transitions and minimal patient disturbance.

Indicators of success

Patient stops shivering.
Patient reports feeling warmer.
Skin to the touch feels warmer.
Improved mental status (if previously impaired).

Related outdoor skills

Author: Wild10 EditorsPublished October 3, 2026Updated October 14, 2026

Educational reference only. Wilderness conditions change fast — practice in low-stakes settings, take a certified wilderness first-aid course, and confirm regional regulations before you rely on any of these skills in the field.