Posted by brianc on January 18, 2001 at 09:45:53:
In Reply to: Get this book posted by JRM on January 18, 2001 at 09:07:22:
But, get it through DAN to help support dive medicine research.
http://www.diversalertnetwork.org/
Basically, it is believed that any gas can be narcotic at a gas-dependant partial pressure. Disruption of synaptic signaling is the proposed mechanism (at least it was the last time I covered this subject in a class). OxTox can take the form of CNS tox or pulmonary tox. Pulmonary tox typically requires about 12 hours exposure to 100% O2 at 1 atm (PPO = 1.0), so it is really not a concern for recreational divers. CNS tox occurs at higher PPO's with shorter exposure time, but varies by indiviual and can vary by circumstance. The real nasty part is that there are typically no warning signs of an impending OxTox reaction. Initial OxTox reactions consist of spasms. On land recover is rapid when PPO is lowered. Under water...well, its hard not to inhale water while convulsing.