Military Resuscitation: Lessons from Recent Battlefield Experience

Small reductions in skin temperature after onset of a simulated hemorrhagic challenge improve tolerance in exercise heat-stressed individuals

“…an exercise heat-stressed and hemorrhaging individual, substantial reductions in skin surface temperature may be difficult to obtain in a field setting and may result in undesirable reductions in core temperature (15) and increases in blood pressure above baseline (58). When considering the capacity of reductions in skin temperature to help treat an already hemorrhaging and heat-stressed individual, it is perhaps most ecologically valid to reduce skin temperatures after the onset of a simulated hemorrhagic challenge.…”

“…Substantial whole body cooling of a previously heat-stressed individual before the onset of upright tilt or LBNP improves blood pressure control (37,62) and is suggestive of an improved tolerance to central hypovolemia and LBNP. The prevention of hypothermia is critical in an individual who has received a hemorrhagic injury (15), and therefore substantial reductions in whole body skin temperature may be undesirable in this context if they lead to reductions in core body temperature. Furthermore, if cooling is to be used as a therapeutic strategy in treatment of a hemorrhaging individual it would be utilized after the onset of the hemorrhagic insult.…”

“…Furthermore, these data suggest that even small reductions in whole body skin surface temperature of an otherwise exercise heat-stressed individual can improve tolerance to a simulated hemorrhagic challenge if they are applied after the onset of a hemorrhagic insult. In a military setting, for example, this may have important implications for the treatment of a wounded and exercise heatstressed soldier and could perhaps be administered via "buddy care" at the point of tactical field care (15).…”

“…These substantial reductions in whole body skin temperature are likely to be difficult to achieve in situations in which access to extensive cooling equipment may be limited, such as in a field setting. Substantial reductions in skin temperature may also be undesirable in the treatment of a hemorrhaging individual in order to avoid both hypothermia, which is problematic even in hot environments (15), and large increases in blood pressure above baseline, which would violate the principle of permissive hypotension in the treatment of a hemorrhaging individual (58). Given that small differences in skin temperature between~38°C and 36.5°C can influence LBNP tolerance after exercise heat stress (45), substantial reductions in whole body skin temperature to 29 -33°C may not be necessary to improve tolerance.…”

Damage control resuscitation initiated in the prehospital and transport setting: A systems approach to increasing access to blood transfusion

“…Given that the peak incidence of hemorrhagic deaths is within 3 hours after injury, early resuscitation with appropriate fluids in combination with strategies to control blood loss makes intuitive sense and can be life-saving. 4,5 The use of prehospital crystalloid and colloid resuscitation strategies has not been shown to improve survival, with a major prehospital clinical trial stopping early due to possible harm to patients who did not receive blood. 6 Using blood products to resuscitate patients in hemorrhagic shock is not new.…”