Resistance of the human body to the action of high partial pressures of nitrogen and methodological aspects of its assessment

The purpose of the study was the development of an algorithm for assessing the resistance of the human body to the action of high partial pressures of nitrogen.
Materials and methods: 125 divers were enrolled in the study. The subjects were placed in a diving pressure chamber, where the air pressure was increased to 0,8 MPa (70 m water column). Before the pressure increase and under maximum pressure, the following functions were assessed in the subjects: attention — using the Landolt’s rings visual acuity test, verbal-color interference (Stroop test) and «Numbering»; thinking — using the methods of addition and subtraction with switching using the Kraepelin table, arithmetic tests «addition in the mind», «multiplication in the mind» and «subtraction in the mind»; small muscle activity — using the Bennett test, the squares test and macrography.
Results and discussion. As a result of comparative and discriminant analyzes, out of ten methods and twenty-two indicators used in the practice of medical support for dives, two were selected, allowing with a high degree of reliability to identify the degree of change in the functioning of the central nervous system under the action of high partial pressures of nitrogen. On the basis of changes in the data processing rate in the visual analyzer and thinking processes, the resistance of the human body to the action of high partial pressures of nitrogen is determined.

marine medicine, resistance, raptures of the deep, diver, algorithm