Prehospital – TCCC

1. Take early and aggressive steps to prevent further body heat loss and add external heat, when possible, for both trauma and severely burned casualties.
2. Minimize casualty’s exposure to cold ground, wind, and air temperatures. Place insulation material between the casualty and any cold surface as soon as possible. Keep protective gear on or with the casualty if feasible.
3. Replace wet clothing with dry clothing or another thermal barrier (i.e. sleeping bag), if possible, and protect from further heat loss. If unable to replace the dry clothing, wrap an impermeable vapor layer around the casualty. Leave the vapor barrier in place until a warm environment has been reached.
4. Place an active heating blanket on the casualty’s anterior torso and under the arms in the axillae (to prevent burns, do not place any active heating source directly on the skin or wrap around the torso). Avoid placing the heat in high pressure areas (i.e. on the back of a supine patient). Regularly monitor the skin under these areas for burns. 25,26,27 See below for information on hypothermia wraps.
5. Enclose the casualty with the exterior impermeable enclosure bag. As soon as possible, upgrade hypothermia enclosure system to a well-insulated enclosure system using a hooded sleeping bag or other readily available insulation (i.e. wool blankets) inside the enclosure bag/external vapor barrier shell. The HPMK is non-insulated and therefore suitable only for short term hypothermia prevention, especially in cold climates.
6. Pre-stage an insulated hypothermia enclosure system with external active heating for transition from the non-insulated hypothermia enclosure systems; improve upon existing enclosure system when possible.
7. Use a battery-powered warming device to deliver IV resuscitation fluids, in accordance with current TCCC guidelines, at flow rate up to 150 ml/min with a 38°C output temperature. (See Appendix A.)
8. Protect the casualty from exposure to wind and precipitation on any evacuation platform.
9. The priority remains the recognition of shock and implementation of heat-loss prevention techniques as outlined above. Rewarming hypothermic patients can be achieved passively (utilizing the patient’s heat generation via shivering/metabolism) and actively (applying an external heat source). If available, active re-warming should be initiated along with passive warming interventions.
10. Active heating: there are no contraindications other than do not use on a heat casualty or those not at risk for hypothermia.28,29 See Figure 2 for the indications, contraindications, and other considerations for active rewarming below.
11. Regarding extremity/trauma and tourniquets, research is ongoing regarding the use of extremity tourniquets.30 Priority in TIH is to prevent additional core cooling to mitigate the effects of shock, hypothermia, coagulopathy, and acidosis. Providers may consider leaving the extremity with a tourniquet outside of the insulating wrap, in order to monitor for re-bleeding. This is not recommended as standard practice as the priority should be on the life saving measures of TIH prevention.
12. Utilize an insulated hypothermia wrap with an active heating source for all potentially hypothermic trauma patients. Systems that include more insulation and active heating sources perform better for treating/preventing hypothermia but may present limitations when considering portability for field applications.5,24 One of the more widely used systems due to portability, cost, and effectiveness is the HPMK which contains the Ready-Heat Blanket (RHB) - an active warming source and the HRS - essentially an impermeable vapor layer (previous version was the Blizzard blanket).
13. Other options include user assembled kits or commercial hypothermia kits, but the recommended characteristics of any hypothermia prevention/treatment system are outlined below. A list of active and passive external rewarming options for field use are shown in (Table 2 - Appendix A).
14. Burrito wrap concept with 5 layers as referenced per Bennet et al.
15. Active heat source applied to the torso in the following order of precedence: axillae, chest, back. These are the areas with the highest potential for heat transfer.24,25,31 The heat source should not be in direct contact with the patient’s skin.
16. Internal vapor layer (plastic or foil sheets)
17. Hooded sleeping bag or other insulation (wool blankets)
18. Complete with an outer impermeable layer wrapped around all other layers to prevent heat loss, water entry and to block the wind.25
19. Use a ground-insulating pad