Clinical Review

Monitoring Heat Injuries in a Hazmat Environment

Fed Pract. 2016 February;33(2):24-29

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In 2012, Elsaesser and colleagues suggested that concern regarding overcorrection of hyponatremia might be exaggerated in the setting of exercise-induced hyponatremia. Indeed, the only cases of death associated with exercise-induced hyponatremia have been in the setting of no treatment or slow correction of hyponatremia with normal saline.²⁴

Conclusions

The issue of heat injury in athletic and military environments plagues participants and leaders alike. This article has sought to shed light on mechanisms that are helpful in mitigating heat injury. Football equipment and military protective gear that diminishes that ability to dissipate heat through the retardation of evaporation, convection, and radiation is a key factor in the development of heat injury.

Personal protective equipment is the most hazardous environment for the development of heat injury. This protective gear along with increased environmental humidity, elevated temperature, and increased workload create a dangerous environment for the individuals involved. Careful monitoring of vital signs is an important factor in avoiding heat injuries.

This article proposes that vital signs along with strict monitoring of mental status through (1) orientation; (2) simple task completion; (3) thought processes; and (4) cognitive ability over time combine to be a powerful deterrent to heat injury in an austere and dangerous working environment. It would be cavalier to propose that all heat injuries in any environment could be avoided by following these guidelines, and more tools to avoid heat injury will be developed. But medical providers trained not only to use vital signs, but also monitor and respond to mental status changes in the patient can mitigate heat injuries more effectively. Finally, careful attention should be placed on correcting hypo- and hypernatremia when rehydrating individuals in this challenging environment.

Acknowledgements
The authors wish to thank the following for their contribution to this manuscript: Sarah M. Paulsen, REB Smith, and the entire CERF-P leadership of the Utah National Guard.