Deep bruise or blister?

[jdiverhenley]

What happens if you get a bruise or a deep blister at depth?
Does the fluid retention in the tissue off gas like everything else or is it sealed in the effected area?

I just got some weird blisters on my fingers, where I hit them underwater trying to grab my camera.

Thanks
Jason

 

[doctormike]

What happens if you get a bruise or a deep blister at depth?
Does the fluid retention in the tissue off gas like everything else or is it sealed in the effected area?

I just got some weird blisters on my fingers, where I hit them underwater trying to grab my camera.

Thanks
Jason

Hi, Jason...

The physics of diving apply to gasses, not to liquids. This is because the volume of a given amount of gas changes with ambient pressure (Boyle's law). While it is technically true that liquids and even solids do change volume under pressure, the effect is trivial and not really measurable in biological systems.

This is also why barotrauma only occurs in spaces in the body that contain trapped air (ears, sinuses and occasionally teeth).

So while damaged tissue may offgas dissolved nitrogen at different rates than normal tissue. any redistribution of fluid at depth (such as bleeding into a tissue space) would not be affected by ascent or descent.

Mike

 

[Dr Deco]

Hello Jason:

Fluid Blisters

As Dr Mike wrote, the fluid in a blister will not move into or out of the body. Hydrostatic pressure is equal. The same is true for a cut, blood will not squirt out, nor will the ocean rush in.

Gases

I did get the impression that you were actually asking about dissolved nitrogen on gassing and off gassing. This will be in proportion to the vascularity of the intact tissue around the blister. These ÅÃlisters were used by Hugh Van Liew PhD to study gas exchange in the tissues of rats several decades ago.


Dr Deco :doctor: