I'm a COPD old fart. I was originally prescribed 2 lpm oxygen for 16 hrs a day. I sleep with a nasal cannula/concentrater connection. I was comfortable without oxygen support for long periods during the day but will connect to a portable liquid oxygen supply if I undertake anything really "strenuous". Recently I suddenly began to experience exaggerated breathlessness. The only relief is to increase my liquid oxygen supply from 2 lpm to 4 lpm (the concentrater is locked at 2 lpm). At rest my breathing returns to "normal" But when I lie down the breathlessness becomes worse and I have to sit up and attempt to "cough up". My sputum is not discoloured but, again recently, I have been finding it increasingly difficult to bring it up. I know that COPD is degenerative but does that imply that it will suddenly go from bearable to unbearable in the space of 24 hours. Or could it be that I am suffering an infection without the usual indicators? I have an emergency pack of Amoxicillin and Prednisolone and have booked a date with my respiratory team . Has anyone out there experienced this phenomenon?