Question about Oxygen

[TheAvatar]

A surface rebreather is a good choice for those with expected long response times.. Dan supposedly has a new design to replace the REMO, at ANDI we sell the SOR which is a simple surface rebreather that can stretch a small cylinder out quite far.. The scrubber is a disposable cartridge and is about $25 (I dont remember the exact cost).

The SOR is set up to rebreathe most of the gas and is similiar in function of an scr to maintain the highest FO2 possible with good gas efficiency and ease of breathing.

I would really love to get a lot more detailed information on the REMO system. I want to know things like operating temp ranges, scrubber life, what scrubber chemicals are used (LiOH?), real world achievable %O2 delivery numbers, what flow rates one can achieve, a real world range of how long it really can extend a Jumbo D cylinder, etc etc etc.

 

[Dr Deco]

Hello Readers:

100% and Diluted Oxygen

I looked into some calculated rates of tissue inert gas washout with 100% as compared with diluted oxygen. It turns out that undiluted (100%) is better. One will drop the dissolved nitrogen loads faster, even with short oxygen exposures of 20 minutes, with pure oxygen. If the oxygen is allowed to flow more slowly and become mixed with air, the best that you would drop is to the nitrogen tension of the inspired gas (pure plus air diluent) that leaks in - even after hours of breathing.

Physiology

One wishes to reduce the gas tension rapidly when neurological problems are encountered. Because the free gas phase is often in the circulatory system supplying nerves (and blocking the capillaries), you wish to have these bubbles shrink quickly and perfusion be reestablished.

Also the smaller the bubble, the greater is the effect of surface tension. Large bubbles (> 10 microns) will not be influenced much by surface tension effects. When the bubbles are but a few microns in diameter, surface tension will play a big role. This would play a role in extravascular bubbles, while intravascular one would be washout out of capillaries when they become this small.

Dr Deco :doctor:

Readers, please note the next class in Decompression Physiology :1book:
http://wrigley.usc.edu/hyperbaric/advdeco.htm