Transcutaneous Monitoring of Oxygen Tension during Progressive Hypoxia and Sleep

Abstract

Transcutaneous O₂ monitoring (P_tc(O₂) was studied in 16 adult subjects suspected of having sleep-related breathing disorders, by comparison with arterial O₂ measurements (P_aO₂) At rest the mean difference (±SD) between P_a0₂ and P_tcO₂ was 3.6 (±1.5) kPa. During progressive hypoxia 74 simultaneous measurements showed a mean decrease in P_tcO₂ from the beginning to the end of the hypoxic tests of 6.6 (± 1.4) kPa for P_tcO₂ and 7.1 (± 1.5) kPa for P_aO₂. The decrease in P_tcO₂ was slower than that in P_aO₂ during the first minute (p<0.001), but for the whole hypoxic period there was no difference in the rate of decrease between the two methods. Continuous P_tcO₂ monitoring has been found useful in detecting respiratory abnormalities during sleep.