The Burrito or Hypothermia Wrap

A widely applied method to protect a victim of hypothermia is called the Burrito Wrap. The name seems to come from the method used to serve burritos, with several layers of wrapping material, and the result looking like an oblong cocoon. It may also be called a Hypo Wrap (for hypothermia). 

Improvised Burrito Wrap for Marine SAR

The material below proposes a Burrito Wrap modified for marine search and rescue where the victim has been pulled from the water or taken off a boat suffering from exposure. That is, the victim has been immersed in salt water or has wet clothing from salt spray, rain, or snow. It is assumed that medical treatment, e.g., BC Ambulance, will be available nearby and the RCMSAR vessel will be used to transport the victim for further treatment.

The Main Layers in the Wrap

There are three main layers in the wrap:

Innermost: Vapour barrier. This layer keeps heat from leaking away from the victim and keeps the middle layer of the wrap dry so that layer will provide the maximum amount of insulation.   

Middle: Insulation. This layer prevents further leakage of heat from the victim's body. It will work best when it is dry. 

Outermost: Protection from the elements. This layer prevents the middle layer (insulation) from getting wet from the elements. It may not be needed if the victim is inside a (dry) cabin; but anticipate the victim will have to be removed from the cabin and may be exposed to the elements at that time. 

For a victim in the wilderness there may be an additional layer between the body and the ground for comfort and extra insulation. In marine search and rescue this may be less critical: if the victim will be lying on a padded bench seat inside the boat's cabin, this layer may not be needed. However, if the victim will be lying on a cold metal deck, consider using this additional layer. 

Specially-designed Wraps and Improvised Wraps

There are variety of purpose-built wraps available. Where this is used, follow the attached directions.

Where purpose-built wraps are not available, they can be improvised, as described below. 

The Innermost Layer. This layer is mainly intended to be a vapour barrier. This is shown as a layer of clear plastic in the image above. Alternatively, a space blanket is highly suitable for use in this layer. Due to the size of many space-blanket products it may be appropriate to combine two, with some overlap. The objective is to be able to wrap the full body of the victim within the innermost layer, except for the face. Using space blankets for the innermost layer will ensure that there is very little heat transmission due to evaporation or to radiation. Sealing the innermost layer should ensure that there is little air circulation to the outside, reducing heat loss due to convection. 

The Middle Layer. This layer is intended to provide insulation for the victim. It will inhibit conduction of heat from the air and clothing that is immediately next to the body to the outside. A wool blanket (as in the image) or a sleeping bag should work well. The innermost and outermost layers should be constructed so that the middle layer does not get wet due to water in the victim's clothing or from the outside elements. When the middle layer gets wet its insulation property will be reduced. As with the innermost layer, the middle layer should be completely sealed before applying the outermost layer, although with the face exposed for monitoring the victim. 

The Outermost Layer. This layer should provide protection from the elements. It is not strictly necessary if the victim is sheltered inside the warm cabin of the rescue vessel. But the victim will eventually have to be moved ashore. It is best to anticipate this and build this layer into the wrap from the outset; the objective is to avoid unnecessarily disturbing the victim when the time comes to relocate. A suitable material for the outermost layer is a tarp (as in the image), generally readily available on board a rescue boat. 

Additional Heating

There should be chemical-heating gel packs on board rescue vessels. These are plastic pouches containing a chemical compound that will generate heat when activated. Follow the directions on the pouch. Generally the gel is activated by squeezing the pouch. The directions may advise that activated pouches should not be applied directly to bare skin. 

The best locations for applying these heating pouches to a victim are at the throat, armpits, across the chest, and in the groin area. They should go onto the body inside the innermost layer of the wrap. Again: follow directions on the pouch. 

Monitoring the Victim

The condition of the victim should be monitored regularly while they are in the wrap. The face should be exposed so various signs can be seen. Follow first aid procedures to periodically monitor the ABCs. 

Transfer of the Victim

At some point the victim will be handed over to medical personnel on shore. When conducting the transfer, explain to the medical personnel that you have treated the victim for hypothermia. Handle the victim with gentle care and continue to keep the victim in a horizonal position. 

Maintain a Record

As for all first aid procedures, maintain a record. This should include results of monitoring vital signs and any first aid that has been administered. When turning the victim over to medical personnel, provide the record and explain how the wrap was applied. Upon receipt of the victim, the medical personnel may wish to open the wrap to make their own observations and to conduct their own diagnosis of their patient. 

Steps for Applying a Wrap On Board a Small Vessel

The steps below assume that the victim has been brought on board using a spine board and is currently on the spine board with the board flat on the deck.

1. Prepare the wrap materials on a padded bench seat before the victim is moved into the cabin. If the wrap material is a "pre-packaged" specially designed component have it open and ready for use. If it consists of layers of improvised material, have all of the layers assembled and open to receive the victim. 

2. Move the spine board with the victim to lie on the deck adjacent to the bench. Be gentle and keep the victim horizontal.

3. With appropriate crew (probably four people, one at the head, one at the feet, and two adjacent to the torso) carefully lift the victim off the spine board and lay the victim along the bench seat in the middle of the wrap material.

4. Activate any heating pads that are available and apply to the victim as appropriate. 

5. If the wrap material is a pre-packaged specially manufactured item, follow directions. If the wrap material has been constructed of available items (e.g., "space blanket" for innermost, blanket or sleeping bag for middle, and tarp for outermost layers), close each one in sequence; the objective should be that each layer should be sealed to be the most effective for its purpose.

6. Ensure ready access to the face and head so the victim can be monitored while on route to medical support. 

7. If the victim needs to be moved again (taken off the boat), place the spine board on the deck adjacent to the bench seat and gently lift the victim from the seat to the spine board. Keep the wrap in place until the victim is in the ambulance, unless told otherwise.  

2-3 Alternative. To avoid having to lift the victim from the deck up onto the bench seat, there is an alternative. With the victim still on the back board, place the board along the bench seat with a gap between the edge of the back board and the back of the bench. Then roll the victim gently onto his or her side off the back board towards the back of the bench. The victim should then be lying on his or her side facing the back of the bench, and mostly off of the back board.  Remove the back board and roll the victim so they are lying in the middle of the wrap on their back. Continue with step 4. 

7 Alternative. The victim can be rolled gently toward the back of the seat and the spine board inserted next to the victim. Then the victim can be rolled back so he or she is lying on the spine board. An alternative that may be much better is to have BC Ambulance personnel come onto the boat with their own equipment and deal with the issue. 

Wet Clothing. In general for marine search and rescue we do not remove wet clothing. The Burrito Wrap is generally enough to prevent further heat loss and can be particularly effective if warming pads are included inside the innermost layer. If transit time to an ambulance will be short (say, less than 30 minutes), it is better to get underway promptly and not to spend time dealing with wet clothing.  

Videos of the Burrito Wrap Procedure. Procedures for preparing a victim with a Burrito Wrap are widely available. The videos are typically for victims found on land in wilderness situations. Some parts of treatment on land will not be required in our situation on board a rescue vessel: in particular having an outer layer (for protection from the elements) and using rope on the outside to tie the burrito wrap together. Generally the victim will be placed inside the boat's cabin and that will provide protection (and some heating). Constant supervision and a short travel time means the victim will not need to be tied into the wrap. Apart from these differences, most procedures for wilderness first aid can be adapted directly for use in marine search and rescue.