Studying Quantitative Relationships Between the Indicators of Physical Development at Birth and the Functional State of the External Respiratory System

Abstract

The external respiration system is studied in various areas of human physiology and ecology in order to both identify the patterns of functioning of this system and to assess the nature and extent of the influence of environmental factors on respiratory function.Indicators of the external respiration system are considered as individual indicators of the body's adaptation to the environment. The result of the influence of unfavorable environmental factors is most pronounced in the period of intrauterine development and largely determines the functional capabilities of the organism in the later periods of ontogenesis.The aim of our work was to study the relationship between birth weight and expiratory flow rates. 500 children aged 4 to 7 years were examined. With age, there is an increase in the volumetric expiratory flow rate, which is associated with the processes of general development and growth of the body. The results of the analysis of variance also indicate that this relationship is statistically significant. The value of the Fisher coefficient (F) is 6.73 at a significance level of 0.00021. The greatest increase in expiratory volume flow rates is observed between four and five years (0.54 l/s or 54%), between six and seven years (0.36 l/s or 36%), and the increase between five and six years is insignificant (p>0.05).In the course of our research, the dependence of the indicators of the volumetric expiratory velocity on the floor was also established. In boys, this figure was 1.34 l/s, in girls ‐ 1.19 l/s. This difference was also significant after taking into account age (p<0.05).To identify the nature of the influence of anthropometric parameters at birth on the value of the volumetric expiratory flow rate, a multiple regression analysis was carried out, taking into account birth weight, birth length and age. To clarify the nature of the relationship under study, partial correlation coefficients were calculated, which showed that age and birth weight have the greatest influence on expiratory PTM. Body length at birth does not have a significant effect on external respiration. The partial correlation coefficients are as follows: body weight at birth – 0.244451; age – 0.569063; body length at birth – ‐0.156432.Since we found that there are certain differences in the expiratory flow rate between boys and girls, we performed a regression analysis for each group. Thus, we can conclude that the indicators of external respiration increase with age due to the processes of growth and general development of the body. The results of the regression analysis of the influence of anthropometric parameters on the volumetric expiratory flow rate indicate the greatest influence on PTM of age and body weight at birth, both in boys and girls.