Room oxygen enrichment improves sleep and subsequent day-time performance at high altitude
Andrew M. Luks, Harm van Melick, Rodolfo R. Batarse, Frank L. Powell, Igor Grant and John B. West
Respiration Physiology
Volume 113, Issue 3, 1 September 1998, Pages 247-258

Abstract We carried out a randomized, double-blind trial at 3800 m altitude to test whether a small degree of room oxygen enrichment at night improves sleep quality, and performance and well-being the following day. Eighteen sea-level residents drove from sea level to 3800 m in one day, and then slept one night in ambient air, and another night in 24% oxygen, the order being randomized. With oxygen enrichment the subjects had fewer apneas (P < 0.01) and spent less time in periodic breathing with apneas (P < 0.01) than when they slept in ambient air. Subjective assessments of sleep quality were also significantly improved. There was a lower acute mountain sickness score during the morning after oxygen-enriched sleep (P < 0.01) and a greater increase in arterial oxygen saturation from evening to morning (P<0.05). The larger increases in arterial oxygen saturation from evening to morning suggest that the control of breathing may have been altered. Installing an oxygen-enriched room at high altitude is relatively simple and inexpensive, and shows promise for improving well-being of both commuters and residents.

Six Percent Oxygen Enrichment of Room Air at Simulated 5000 m Altitude Improves Neuropsychological Function
Andre B. Gerard, Michele K. McElroy, Michael J. Taylor, Igor Grant, Frank L. Powell, Sebastiaan Holverda, Nicole Sentse, John B. West. High Altitude Medicine & Biology. March 1, 2000, 1(1): 51-61. doi:10.1089/152702900320685.

Safe Upper Limits for Oxygen Enrichment of Room Air at High Altitude John B. West. High Altitude Medicine & Biology. March 1, 2001, 2(1): 47-51. doi:10.1089/152702901750067918.

Department of Medicine, University of California San Diego, La Jolla CA 92093-0623.

Oxygen enrichment of room air at high altitude has been shown to improve mental performance, sleep quality, and work capacity. Until now, the usual strategy has been to use an oxygen concentration that reduces the equivalent altitude to about 3000 m, where the equivalent altitude is that which gives the same inspired PO2 during air breathing. However, standards adopted by the National Fire Protection Association allow considerably higher oxygen concentrations without introducing a fire hazard. For example, by raising the oxygen concentration to 31.5% at an altitude of 5000 m, the equivalent altitude can be safely reduced to less than 2000 m. At the extreme altitude of 8000 m, the equivalent altitude can be reduced to less than 4000 m without increasing the fire hazard. These increased levels of oxygen enrichment are feasible in practice using oxygen concentrators. They may be useful if lowlanders need to ascend rapidly and stay at high altitude, or for treating people with high altitude illnesses.