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Correlation of NIRS Determined Cerebral Oxygenation with Severity of Pilot +Gz Acceleration Symptoms

  • Paul B. Benni
  • John K-J. Li
  • Bo Chen
  • Joseph Cammarota
  • David W. Amory
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 530)

Abstract

Pilots commonly experience decreased peripheral vision, confusion & disorientation, and/or unconsciousness when exposed to high +Gz acceleration. We correlated NIRS determined ΔHb, ΔHbO2, and ΔTotalHb with the resultant +Gz stress symptoms that subjects reported after experiencing a 6 to 10 +Gz amplitude pulse. During the hyperemic response phase following the +Gz pulses, an increase of the averaged peak values of ΔHbO2 and ΔTotalHb as a function of the severity of the subjects’ symptoms was observed. Significant increases were found for the averaged peak values of ΔHbO2 and ΔTotalHb between high vision loss, confusion and disorientation while remaining conscious (A-LOC), and unconsciousness (G-LOC). The results suggest that the confusion and disorientation associated with A-LOC is physiologically based and that A-LOC is an intermediate +Gz stress symptom between high peripheral vision loss and G-LOC. Like G-LOC, pilots who experience A-LOC symptoms momentarily do not have full control of their aircraft.

Key words

A-LOC Cerebral oxygenation +Gz acceleration +Gz stress G-LOC (G-induced loss of consciousness) NIRS (Near-Infrared Spectroscopy) 

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Copyright information

© Springer Science+Business Media New York 2003

Authors and Affiliations

  • Paul B. Benni
    • 1
    • 2
  • John K-J. Li
    • 1
  • Bo Chen
    • 1
    • 2
  • Joseph Cammarota
    • 3
  • David W. Amory
    • 4
  1. 1.Dept. Biomedical EngineeringRutgers UniversityPiscatawayUSA
  2. 2.Dept. AnesthesiaUMDNJ-Robert Wood JohnsonNew BrunswickUSA
  3. 3.EDO M-TechnologiesHuntingdon ValleyUSA
  4. 4.Institute of Applied Physiology and MedicineSeattleUSA

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