Oxygen regimen in the human peripheral tissue during space flights

Area of Science:

• Space Medicine
• Human Physiology in Space
• Aerospace Physiology

Background:

• The INTER-KOSMOS program investigated the physiological effects of spaceflight on cosmonauts.
• Previous studies have indicated potential alterations in respiratory and metabolic functions during prolonged space missions.

Purpose of the Study:

• To analyze the changes in oxygen parameters (pO2ic and local oxygen utilization) in cosmonauts during spaceflight.
• To assess the impact of spaceflight on respiratory function post-return to Earth.
• To evaluate differences in oxygen regimen dynamics between short-term visiting crews and long-term permanent crews.

Main Methods:

• Analysis of data from the "Oxygen" experiment conducted on the Salyut-6 orbital station.
• Measurement of partial pressure of oxygen in inspired air (pO2ic) and local oxygen utilization.
• Inclusion of hyperventilation testing post-flight for crew members.

Main Results:

• Short-term visiting crews showed a decrease in pO2ic by 3.28 kPa and local oxygen utilization by 0.44 kPa.
• Long-term Salyut-6 crews exhibited a greater decrease in pO2ic (3.8 kPa) and lower values (3.4 ± 0.5 kPa) during flight.
• A statistically significant reduction in peak values (1.39 kPa) was observed during post-flight hyperventilation testing.

Conclusions:

• Spaceflight significantly impacts the oxygen regimen of crew members.
• Long-term space missions lead to more pronounced changes in oxygen utilization compared to shorter expeditions.
• Continuous monitoring of oxygen dynamics is essential for medical supervision of astronauts during spaceflight and readaptation phases.