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Neurological altitude decompression sickness among U-2 pilots: 2002-2009
Sean L Jersey1, Gregory L Hundemer, Rory P Stuart
1David Grant USAF Medical Center, 60 MDTS/SGQX, 101 Bodin Circle, Travis AFB, CA 94535, USA. sean.jersey@us.af.mil
Aviation, Space, and Environmental Medicine
|July 14, 2011
Summary
Increased altitude decompression sickness (DCS) with central nervous system (CNS) effects in U-2 pilots from 2002-2009 was linked to more frequent and longer high-altitude flights. This highlights the need for revised flight protocols to prevent future pilot injuries.
Area of Science:
- Aerospace Medicine
- Neurology
- Physiology
Background:
- U-2 pilots experienced a rise in altitude decompression sickness (DCS) with central nervous system (CNS) involvement between 2002-2009.
- This increase in severity prompted a U.S. Air Force investigation to prevent further pilot incidents.
Purpose of the Study:
- To retrospectively examine neurological DCS cases in U-2 pilots during 2002-2009.
- To identify factors contributing to the increased incidence and severity of CNS DCS.
Main Methods:
- Retrospective analysis of neurological DCS cases among U-2 pilots.
- Utilized existing data sources due to the urgency of the situation.
Main Results:
- 16 confirmed and 4 possible CNS DCS incidents occurred in U-2 pilots.
- A majority of confirmed cases (12/16) and severe incidents were concentrated at one location, correlating with increased combat operations.
- Delayed symptom recognition, symptom recurrence, and persistent neuropsychiatric symptoms were noted, suggesting potential long-term injury.
Conclusions:
- Increased cockpit activity and prolonged high-altitude exposure likely contributed to the rise in U-2 CNS DCS.
- Recommendations include adjusting preoxygenation, cabin altitude, in-flight exercise, and flight frequency to mitigate DCS incidence.
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