Image Source: S, M. (2023, June 01). Illustration of fluid distribution. self. self-made
The fluid shift in the body is an adaption to the reduced gravitation force in space. This results in a shift of the body fluids from the lower body to the upper body.
Detailed Definition:
When a human body
is placed on the earth surface, it has a hydrostatic (gravitational) blood
pressure gradient and every body region has a different arterial pressure.
In the reduced
gravity of space, the hydrostatic pressure in the arteries and veins is altered
to a homogeneous arterial pressure in all regions (which is the original
arterial pressure of the hearth), which results in the shifted fluid
distribution through the body.
The human body reduces the volume of the total fluid and after the space resident, the fluid is shifted because of the returned gravity force.
This phenomenon can cause several issues like cardiac arrhytmia, muscular athropy and visual problems (because the globe is flattened, the blood flow is changed slightly and the diamteter of the optical nerve can increase).
Etymology: fluid - Latin fluidus ("fluid, flowing, moist") shift - Proto-Germanic skiftan (" to divide, change, seperate")
Sample sentence(s):
A medical
effect of a space flight may be a fluid shift.
Nasa is studying
the effect of the fluid shift and how it affects changes in vision.