Intra-shift and Inter-shift Dynamics of Stress Index of Regulatory Systems in Medical Personnel of Mobile Emergency Medical Teams in Modern Conditions

INTRODUCTION: In conditions of spread of the new coronavirus infection SARS-CoV-2 (COVID-19), the work regimen and working conditions of the mobile emergency medical teams have changed, the range of occupational hazards has expanded, which led to unfavorable alterations in the functional state of the nervous system of workers. 
AIM: To study the influence of the professional activity on the functional state of an organism of medical workers of mobile emergency medical teams in conditions of COVID-19 pandemic. 
MATERIALS AND METHODS: Parameters of the functional state of an organism of medical workers of mobile emergency medical teams were studied before, after the work and between shifts in the period from May to October 2021. The extent of centralization of the heart rhythm control was evaluated by use of strain index (SI) of regulatory systems. The sample included 67 workers of mobile teams (21 men and 46 women), 16 doctors and 51 paramedics. The average age of workers participating in the study was 36.28 2.82 years. 
RESULTS: By the end of shift, in more than half the medical workers of mobile EMT, SI grew by 74.75 units (p = 0,021). The age (2 = 6.467; р = 0.040) and length of service (2 = 6.069; р = 0.049) influenced the distribution of workers with different SI dynamics on the basis of the results of the work shift. By the beginning of the next shift, in 60.71% of workers included into the study, a significant increase in SI was recorded on average by 74.02 (р = 0.001) compared to the beginning of the previous shift. The influence of length of service on the distribution of workers with different dynamics of SI in the successive shifts into groups was recorded (2 = 7.313; р = 0.026). 
CONCLUSIONS: The dynamics of the growth of the strain index of regulatory systems indicates low effectiveness of recovery of the functional state of an organism of workers in the period of scheduled rest. The greatest influence on the growth of parameters was exerted by length of service, which indicates the negative impact of working conditions on the functional state of an organism of workers.