[Study on testing method of susceptibility to decompression sickness in aerospace].

Objective. To provide related parameters for astronauts. Method. A study of susceptibility to decompression sickness was carried out in 43 subjects in a hypobaric chamber. Result. Incidence of altitude decompression sickness under rest condition was closely related to age, time of oxygen prebreathing, gas bubble formation rates in the venous blood flow returned to heart and some other physiological indexes. Incidence of decompression sickness was significantly higher in subjects aged 30-36 years than in those aged 19-20 years under the same experimental conditions. In the older subjects body-fat, blood cholesterole and noradrenaline in urine during experiment were significantly higher than those in the younger subjects. It also showed that among persons of the same ages, when prebreathing time was longer, the incidence of decompression sickness was significantly lower under the same experimental conditions. Conclusion. It is desirable that the susceptibility to decompression in astronaut be tested with 1 h oxygen prebreathing before exposure to the altitude of 10000 m for 30 min.