Physiological Evaluation of Cooling Devices in Conjunction With Personal Protective Ensembles Recommended for Use in West Africa.

Abstract

Cooling devices (CDs) worn under personal protective equipment (PPE) can alleviate some of the heat stress faced by health care workers responding to the Ebola outbreak in West Africa. Six healthy, young individuals were tested while wearing 4 different CDs or no cooling (control) under PPE in an environmental chamber (32°C/92% relative humidity) while walking (3 METs, 2.5 mph, 0% grade) on a treadmill for 60 minutes. Exercise was preceded by a 15-minute stabilization period and a 15-minute donning period. The control condition resulted in a significantly higher rectal temperature (Tre) at the end of the exercise than did all CD conditions (CD1, P=0.004; CD2, P=0.01; CD3, P=0.000; CD4, P=0.000) with CD1 and CD2 resulting in a higher Tre than CD3 and CD4 (P<0.05). The control condition resulted in a higher heart rate (HR) at the end of exercise than did the CD3 (P=0.01) and CD4 (P=0.009) conditions, whereas the HR of the CD1 and CD2 conditions was higher than that of the CD3 and CD4 conditions (P<0.05). Weight loss in the control condition was higher than in the CD3 (P=0.003) and CD4 (P=0.01) conditions. Significant differences in subjective measurements of thermal stress were found across conditions and time. Use of CDs can be advantageous in decreasing the negative physiological and subjective responses to the heat stress encountered by health care workers wearing PPE in hot and humid environments. (Disaster Med Public Health Preparedness. 2017;11:573-579).