Effect of Moderate Elevation above Sea Level on Blood Oxygen Saturation in Healthy Young Adults

Abstract

Background: Arterial hemoglobin oxygen saturation (SaO₂) decreases at an altitude of >1,500 m. There are no reports on normal SaO₂ at altitudes between 0 and 1,500 m. The clinical significance of decreased SaO₂ at such altitudes is unclear. Objective: To test the hypothesis that in healthy volunteers normal SaO₂ at moderate altitude (MA; 725 m) is lower than that at almost sea level (SL; 43 m). Methods: SaO₂ was measured by transcutaneous pulse oximetry in young healthy volunteers at MA and was compared to equivalent measurements at SL. In addition, a 6-min walk test was performed and SaO₂ at the end of the walk was compared between the two locations. Results: 111 males were checked at MA and 101 at SL. At rest, nadir SaO₂ was 95% at MA compared to 97% at SL. Mean SaO₂ at rest was slightly higher at SL (98.53 ± 0.52) compared to MA (98.11 ± 0.8; p < 0.01). In subjects who completed the 6-min walk test, SaO₂ slightly decreased after the test in both locations, by 0.38 ± 0.65% in the SL group and by 0.37 ± 1.12% in the MA group. This difference is not statistically significant by univariate analysis; however, a multiple regression analysis indicated that the drop in SaO₂ was higher at MA than at low altitude. Conclusions: We found a low but significant difference in SaO₂ between near-SL and at an altitude of 725 m. The clinical significance of this difference, in terms of human health, is probably minimal.

Association of elevation, urbanization and ambient temperature with obesity prevalence in the United States

“…Prior studies have evaluated the way oxygen saturation varies by elevation. 32,33 In the future, use of oxygen saturation prediction models or pressure altitude could be used rather than topographical elevation to better model the underlying constructs.…”

Sex‐linked difference in blood oxygen saturation

“…Many factors are known to influence the SpO 2 values. Among them: age, body temperature, blood pH, partial CO 2 and O 2 pressures, altitude and barometric pressure . It is not known whether sex also influences SpO 2 .…”

“…Among them: age, body temperature, blood pH, partial CO 2 and O 2 pressures, altitude and barometric pressure. [2][3][4] It is not known whether sex also influences SpO 2 . In recent years there has been a growing interest in studying differences between sexes, both from a physiological and a clinical perspective.…”

Cyclic Hypobaric Hypoxia Improves Markers of Glucose Metabolism in Middle-Aged Men

“…A final limitation is that the oxygen saturation was not measured in the sham group (SH), as we did not expect to find significant changes in SH oxygen saturation at such low simulated altitude. Recent studies have shown that exposure to low altitudes result in small, clinically insignificant decreases (0.42%) in oxygen saturations (Goldberg et al, 2012). Even if a decrease occurred in oxygen saturation in SH subjects, it would have minimized, rather than exaggerate, the differences between the groups.…”