I am new here. I use a Cpap with 02 @ night @2 liters my o2 had dropped to 84% help a lot with my fatigue for 6 months my fatigue is back I sleep good, I am waking up tired again I hate it cause I can't do the things I need to do. I lay back down after a couple of hours use Cpap machine with O2. Still am very tired. Has anyone went thru this? Also middle of chest pain thru to back, I have seen Cardiologist everything is fine with my heart. I need total knee replacement surgery and lower back surgery plus carpel tunnel surgery how can I when I do not have the strength to go thru therapy? For all surgies.