Differing Oxygen Concentrations and the Effect on Post-Hypoxia Recovery
Abstract
Given the consistent rise in hypoxia-like in-flight emergencies and the negative effects of hypoxia on human performance, it is important to garner a more complete understanding of performance recovery following a hypoxic event. Previous research has reported that use of differing oxygen concentrations following a hypoxic event has resulted in dissimilar recovery profiles. The goals for this study were to examine operator performance on a tracking task and regional oxygen saturation of the frontal lobes of the brain during a hypoxic event and to document differences in performance recovery for two commonly used recovery gas oxygen (O2) concentrations (100% vs. 21%). Ten subjects completed a tracking task while being exposed to a 25,000-foot equivalent O2 concentration (~7%) using the reduced oxygen breathing device for 5 minutes. Each exposure was preceded by a 5-minute baseline, with subjects breathing 21% O2, and was immediately followed by a 5-minute recovery period, during which either 21% or 100% O2 was administered. Tracking task performance and regional oxygen saturation were surveyed during these periods and for an additional 15 minutes following the exposure and again at 30 minutes and 1, 2, 3, 4, and 24 hours following the exposure to catalogue remaining performance deficits, all while breathing 21% O2. A repeated measures analysis of variance revealed no significant differences between the speeds at which participants recovered from hypoxic exposure, regardless of which O2 concentration was used. With regard to tracking task performance, results of this study indicate that participants recover immediately following administration of both the 100% and 21% O2 recovery gases. Thus, there was no delay in recovery, and the administration of 100% O2 following the exposure did not lead to increased deficits in performance as previously observed. Regional oxygen saturation values also recovered at similar temporal rates, regardless of recovery gas concentration.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 15, 2018
- Accession Number
- AD1052173
Entities
People
- Jeffrey B. Phillips
- Matthew E. Funke
- Todd R. Seech
Organizations
- Naval Medical Research Unit Dayton