G-LOC

Revision as of 02:56, 9 August 2012 by WikiBot (talk | contribs) (Bot: Automated text replacement (-{{SIB}} + & -{{EJ}} + & -{{EH}} + & -{{Editor Join}} + & -{{Editor Help}} +))
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search

WikiDoc Resources for G-LOC

Articles

Most recent articles on G-LOC

Most cited articles on G-LOC

Review articles on G-LOC

Articles on G-LOC in N Eng J Med, Lancet, BMJ

Media

Powerpoint slides on G-LOC

Images of G-LOC

Photos of G-LOC

Podcasts & MP3s on G-LOC

Videos on G-LOC

Evidence Based Medicine

Cochrane Collaboration on G-LOC

Bandolier on G-LOC

TRIP on G-LOC

Clinical Trials

Ongoing Trials on G-LOC at Clinical Trials.gov

Trial results on G-LOC

Clinical Trials on G-LOC at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on G-LOC

NICE Guidance on G-LOC

NHS PRODIGY Guidance

FDA on G-LOC

CDC on G-LOC

Books

Books on G-LOC

News

G-LOC in the news

Be alerted to news on G-LOC

News trends on G-LOC

Commentary

Blogs on G-LOC

Definitions

Definitions of G-LOC

Patient Resources / Community

Patient resources on G-LOC

Discussion groups on G-LOC

Patient Handouts on G-LOC

Directions to Hospitals Treating G-LOC

Risk calculators and risk factors for G-LOC

Healthcare Provider Resources

Symptoms of G-LOC

Causes & Risk Factors for G-LOC

Diagnostic studies for G-LOC

Treatment of G-LOC

Continuing Medical Education (CME)

CME Programs on G-LOC

International

G-LOC en Espanol

G-LOC en Francais

Business

G-LOC in the Marketplace

Patents on G-LOC

Experimental / Informatics

List of terms related to G-LOC


Overview

G-LOC, abbreviated from G-force induced Loss Of Consciousness, is a term generally used in aerospace physiology to describe a loss of consciousness arising from excessive and sustained g-forces draining blood away from the brain causing cerebral hypoxia. The condition is most likely to affect pilots of high performance fighter and aerobatic aircraft or astronauts but is possible on some extreme amusement park rides. G-LOC incidents have caused fatal accidents in high performance aircraft capable of sustaining high g for extended periods. High-G training for pilots of high performance aircraft or spacecraft often includes the simulation of G-LOC in special centrifuges. Such man-rated centrifuges are made by AMST Systemtechnik in Austria (Austria Metall SystemTechnik), Latacoere in France, the Environmental Tectonics Corporation (ETC) and Wyle Laboratories in the USA.

Effects of g-forces

As g-force increases, or the longer it is sustained, the victim may suffer progressively:

  • Brownout- a loss of colour vision
  • Tunnel vision - loss of peripheral vision, retaining only the centre vision
  • Blackout a complete loss of vision but retaining consciousness.
  • G-LOC where consciousness is lost.

Recovery is usually prompt following removal of g-force but a period of several seconds of disorientation may occur. Brief but vivid dreams have been reported to follow G-LOC.

The human body is much more tolerant of g-force when it is applied laterally (across the body) than when applied longitudinally (along the length of the body). Unfortunately most sustained g-forces incurred by pilots is applied longitudinally. This has led to experimentation with prone pilot aircraft designs which lies the pilot face down or (more successfully) reclined positions for astronauts.

Thresholds

The g thresholds at which these effects occur depend on the training, age and fitness of the individual. An un-trained individual not used to the g-straining manoeuvre, can black out between 4 and 6 g, particularly if this is pulled suddenly. A trained, fit individual wearing a g suit and practising the straining manoeuvre, can, with some difficulty, sustain up to 9g without loss of consciousness. Prone position designs in aircraft have not proved successful and the problem has been addressed largely by the development of the G-suit.


External links

G-LOC, Could It Happen To You? fa:کاهش هوشیاری ناشی از افزایش گرانش ko:G-LOC



Linked-in.jpg