Hi here is a like that describes what lack of oxygen can do to your tissues includingn your heart. I do know first hand that lack of oxygen can cause memory problems, I always felt like I was in a fog. My energy level also was terrible, I basically huffed and puffed my way through the day, any exertion would leave me feeling like a wet dish towel. My blood pressure was also elevated from the extra work my body had to do to get enough O2, 180/120 at it's highest. I was cyanotic after climbing stairs and my heart was working in overdrive, heart rate was about 170. That got much better after I was on O2, my memory improved and so did my blood pressure and heart rate. So...here's that link that describes O2 a bit...
<a target=_blank class=ftalternatingbarlinklarge href="http://www.dentalplans.com/Dental-Health-Articles/Will-I-Need-Oxygen-.asp">Lack of O2 effects</a>
Hugs, Jenn <img src="i/expressions/face-icon-small-smile.gif" border="0">