Abstract: In order to characterize the changing trend of blood gas indices in simulated acute hypobaric hypoxia environment, the BALB/c mice were selected in this study to observe the variation of oxygen saturation, oxygen partial pressure, carbon dioxide partial pressure in arteries and veins blood when the acute hypobaric hypoxia was simulated. The results showed that with the prolongation of exposure time to anoxic environment, the difference of blood oxygen saturation between arteries and veins in BALB/c mice was increased gradually and reached equilibrium after a 24-hour exposure. The difference between arterial and venous oxygen partial pressure showed a trend of decreasing first and then increasing with the prolongation of exposure time to anoxic environment, and that between arterial and venous carbon dioxide partial pressure changed in the opposite trend. The mechanisms associated with the above dynamic change in blood gas indices in BALB/c mice was that with the prolongation of exposure time to anoxic environment, the supply and utilization efficiency of oxygen was compensatively improved so as to adapt to the hypoxic environment.

Key words: simulated acute hypoxia, BALB/c mice, blood oxygen saturation, arterial and venous oxygen partial pressure, arterial and venous carbon dioxide partial pressure