During the day my SATs are fine/good at around 95-98; however, I have a bad time sleeping - it's rare to wake less than 3 times a night because of breathing difficulty/cough etc. Usually, sitting upright and using inhalers eventually does the trick. This morning it didn't and so I measured my SATs and they were 90-92. Even though that's still not bad, is it likely this drop in oxygen is what's causing such broken nights? (It's not sleep apnoea as I was tested for that) and, if so, are there any solutions? I'm permanently tired, and waking breathless is always somewhat frightening!