If your dad is getting co2 overload, cpap even auto cpap,could make it worse. He needs a machine that gives much more expiratory relief like the vpap, and a smart doctor to set it up right for his condition. The co2 overload is making him feel like he's suffocating. A machine that helps him breathe OUT more will help him blow off the CO2 (if his lungs and circ system are working). Your dad really needs a respirologist to work on his case especially if he's going to use cpap. Using cpap at home for CO2 overload is not a do it yourself project.