I think I would need a lot more context to do a real job on this. However, my first inclination would be to invert:
His senses laboured underwater, sound muffled, vision blurred, fear dampened; the (not un)welcome consequences of a lack of sleep.
Yes, I dropped the mention of the neighbour. Maybe that's important. Maybe it belongs in another sentence where the action starts.
Thank you, Rick. I can see how the inversion works here. You've also reminded me that it's better to write in the positive form, the welcome, as opposed to the negative, not unwelcome.