Laser Speckle Contrast Analysis (LASCA) aplicada à avaliação de estresse

Abstract

Despite being physiologically normal, exaggerated and continuous exposure to stress, which exceeds the individual's tolerance capacity, can result in harm to health. The objective of this study was to apply the optical technique Laser Speckle Contrast Analysis (LASCA) to assess stress. This is a cross-sectional, descriptive, experimental study, with a quantitative approach, developed with undergraduate and postgraduate students, at a Higher Education Institution, in São Paulo (SP). The sample consisted of 27 (twenty-seven) participants, randomly distributed. The inclusion criteria were: undergraduate and postgraduate students, of both sexes, aged 18 or over, regularly enrolled. Those who self-reported having cardiovascular complications or using medication that altered cardiovascular functioning, suspected or confirmed pregnancy, physical limitations and women in their menstrual period were excluded. Data collection took place in June and August 2021 and all protective measures were adopted in relation to the coronavirus pandemic. Participants underwent cardiac signal acquisition to analyze heart rate variability, obtained using an electrocardiogram and a Polar V800 heart rate monitor, for 15 minutes. Simultaneously, the LASCA application was developed to obtain images using the MoorFLPI (Full-Field Laser Perfusion Imager) equipment. Next, participants underwent a physical effort test using an electric treadmill for 15 minutes, following the Bruce protocol. After resting for 5 minutes, cardiac signals and LASCA images were collected again, following the same protocols as in the initial phase. The project was approved by the Ethics and Research Committee of Universidade Brasil, under Opinion No. 4.724.843. Equivalent results were found regarding HRV measurements when comparing the LASCA technique and conventional methods, enabling the capture of signs of physiological changes present in the individual's state of stress. Thus, the results point to the feasibility of the LASCA technique to obtain images compatible with the heart rate pulsation pattern from the stress generated in situations of physical effort.