OI Resource - A Resource about Orthostatic Intolerance

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Definitions and Synonyms

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Definitions and Synonyms

Orthostatic Intolerance (OI)

dysautonomia includes forms of Orthostatic Intolerance which include, orthostasis, orthostatic disorder, orthostatic systolic hypotension, systolic hypotension, neurally mediated hypotension (NMH), neurally mediated orthostatic hypotension, delayed orthostatic hypotension, delayed orthostatic intolerance, orthostatic hypotension, postural hypotension, vasovagal syncope, orthostatic diastolic hypotension, diastolic hypotension, orthostatic diastolic hypertension, diastolic hypertension, orthostatic hypertension, orthostatic narrowing of pulse pressure, excessive narrowing of the pulse pressure, orthostatic postural tachycardia, tachycardia after standing for at least 3 minutes, postural orthostatic tachycardia syndrome (POTS), orthostatic tachycardia, chronic orthostatic intolerance (COI)

Orthostatic Intolerance (OI) is a condition where blood pools in the feet and legs when sitting or standing rather than returning to the heart and brain. Orthostatic Intolerance (OI) can be a single illness or problem or it can be a part of many illnesses. Some of these include Chronic Fatigue Syndrome (CFS), Shy-Drager Syndrome, Addison's disease, Parkinson's disease, mitral valve prolapse syndrome, and 10% of diabetics, in addition to affecting people who live in a wheelchair. Symptoms of Orthostatic Intolerance can include fatigue, inability to concentrate, inability to think clearly, dizziness, headaches, and lack of energy. Often these sick people say they feel "almost well" while lying down. There is a simple test for Orthostatic Intolerance.

The results of the Orthostatic Intolerance Test will show either normal blood pressure and pulse or one or more of these 5 forms of OI.

Orthostatic systolic hypotension = big drop in top number
Orthostatic diastolic hypotension = big drop in bottom number
Orthostatic diastolic hypertension = big rise in bottom number
Orthostatic narrowing of pulse pressure = small difference between both numbers
Orthostatic postural tachycardia (POTS) = high heart rate

I have learned that Chronic Fatigue Syndrome (CFS) is not about being tired and not having energy, but is related to Orthostatic Intolerance where blood pools in the feet and legs when sitting or standing. (OI is also a component of many other illnesses besides CFS.) Figuring the g-suit would work the same way it does for fighter pilots and NASA astronauts, I have successfully used the g-suit to relieve some Chronic Fatigue Syndrome (CFS) / Orthostatic Intolerance (OI) symptoms.

Research has already been done that shows successful use of inflatable compression pants (i.e. g-suit and MAST) for Orthostatic Intolerance and Orthostatic Intolerance related illnesses.

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MAST - Military / Medical Anti-Shock Trousers

MAST trousers are compression garments used in emergency situations to treat shock and low blood volume by bringing blood away from the extremities and back to the vital organs. When they are inflated, they are like a whole-body blood pressure cuff.

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g-suit, anti-gravity garment, anti-g suit, antigravity suit, speed jeans, anti-g garment, pneumatic (air) pressure

A g-suit is an anti-gravity garment worn by fighter pilots. When they are pulling positive G's, the suit inflates and prevents blood from pooling in their feet and legs which would cause them to lose consciousness. NASA astronauts also wear g-suits when they experience Orthostatic Intolerance (OI). A standard g-suit is like a pair of chaps, with an air bladder that inflates over 5 areas of the body - at the abdomen, the front of each thigh, and the side of each calf - and cut-outs that allow for mobility at the knees and groin. When manually inflated, a g-suit provides comfortable, gentle, and even air pressure. The compression, which is easily adjustable, aids in blood circulation and diminishes the symptoms of Orthostatic Intolerance (OI). They are MAST trousers that can be lived in. (See also G-suit Pictures.)

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Positive G's

positive G, +Gz, G-force, G forces, G's, Gs, G = gravity

Gravitational (G) forces are experienced on a roller coaster ride. At the bottom of the hill, several positive Gs (+Gz) push one back in the seat. It feels like several times one's body weight. It is usually not enough positive G forces to cause fainting in a healthy person. At the top of the hill, negative G forces lift one out of the seat and a feeling of weightlessness is experienced.

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