This is an observational research study whose purposes are to see the effects of repeated
hyperbaric oxygen therapy treatments on the levels of stem/progenitor cells in peripheral
circulating blood following five days of treatment, 90 minutes per day at 2.0 atmospheres
absolute in 100% USP Grade Oxygen. Hyperbaric oxygen has a greater oxygen concentration than
air at sea level. In this research, the concentration of oxygen will be twice the level of
oxygen at sea level.