Accession Number : ADA333371


Title :   Differences in Mechanism Between Syncope Resulting from Rapid Onset Acceleration and Orthostatic Stress


Corporate Author : AIR COMMAND AND STAFF COLL MAXWELL AFB AL


Personal Author(s) : Self, David A. ; White, Curtis D. ; Shaffstall, Robert M. ; Mtinangi, Benjamin L. ; Croft, Jennifer S.


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a333371.pdf


Report Date : APR 1996


Pagination or Media Count : 41


Abstract : Orthostatically- induced syncope is accompanied by venous pooling and vasodilatation. Loss of consciousness during head-to-foot acceleration (G-LOC) in aviators may be caused by a different mechanism, as venous pooling should be prevented through the use of an anti-G suit. This research was conducted to test the hypothesis that in individuals wearing a well-fitted anti-G garment, there are no important changes in volume of dependent regions during loss of consciousness resulting from rapid onset acceleration stress. Furthermore, this work compares venous pooling patterns in G-LOC subjects to patterns seen during syncope in volunteers and patients subjected to orthostatic stress. The tilt/LBNP tests were conducted to establish what level of venous pooling was required to induce syncope in the absence of a hydrostatic component (other than 1 G) and to confirm that our equipment was sensitive enough to detect volume changes large enough to cause syncope.


Descriptors :   *G SUITS , *ORTHOSTATISM , STRESS(PHYSIOLOGY) , PILOTS , HYDROSTATICS , HYPOTHESES , VEINS , CONSCIOUSNESS , VASODILATION , ACCELERATION TOLERANCE , PRESSURE SUITS , SYNCOPE.


Subject Categories : STRESS PHYSIOLOGY
      PROTECTIVE EQUIPMENT


Distribution Statement : APPROVED FOR PUBLIC RELEASE