Aspectos fisiológicos e cognitivos relacionados ao uso do traje de defesa biológica, nuclear, química e radiológica em militar

Armed Forces must be prepared for a wide range of crises, including Biological, Nuclear, Chemical, and Radiological (BNQR) defense operations. The use of Personal Protective Equipment (PPE) in BNQR situations is mandatory but poses significant physiological and cognitive challenges, such as heat stress. Recent military exercises highlighted fatigue and thermal discomfort in helicopter crews using BNQR PPE, raising questions about physiological and cognitive limits, especially in Brazil, given its vast environmental conditions. This study aimed to conduct a bibliographic review of the physiological and cognitive aspects related to the use of BNQR defense suits in military personnel. This work corresponds to an exploratory and qualitative literature review. The descriptors used were: PPE, biochemical, nuclear, chemical, and radiological defense, physiological variables, cognitive variables, and military personnel. Experimental studies with or without a control group, involving military personnel or protection forces, were selected, while systematic or bibliographic reviews were excluded. The use of BNQR PPE consistently leads to increased heat stress, elevated heart rate, and metabolic rate. The suits impair dexterity, increase task completion time, and reduce overall work time. Cognitive functions, anxiety, and decision-making can also be negatively affected. Various cooling strategies, such as hydration, cooling vests, and limb immersion, have been tested with varying degrees of success in extending tolerance time and reducing physiological strain. It is concluded that BNQR PPE is essential but significantly impairs physiological and cognitive performance due to thermal strain. There is a notable gap in the literature regarding rotary-wing pilots operating in BNQR environments.