I have just come back from a great holiday on the Isle of Skye. We drove across Scotland from Inverness and then settled in to our cottage in Portree overlooking the bay. The boats were quietly moored in the harbour, with the 'Hebridean Princess' (a small cruise ship) a little further out, and the late evening sunshine lighting up the hills in the background. So I settled down for a good night's sleep in a comfortable bed.
I sleep flat (or at least I thought that I did).
Half way through the night came the acid reflux, the first time for months. So I reached over for the gaviscon and then went back to sleep. At home I have rolled up a blanket and put it under the mattress on my side of the bed. It is not much, but it seems to do the trick for me. But I had forgotten to do something equivalent on holiday. And, to be honest, I had forgotten about the blanket under the mattress at home!
I am lucky in that this acid reflux problem at night is not so serious as it is for many others (my oesophagus was repaired after becoming ruptured). The sphincter valve at the top of the stomach is meant to stop the acid or other stomach contents working its way up into the oesophagus. But if you have not got an oesophagus /stomach, you will not have that valve, and then gravity at night tends to let the stomach contents flow up towards your throat.
Some people have adjustable beds that can be raised to help this problem (apparently IKEA do them) whilst others put a brick or two under the feet of the bed (I think that the loved one sleeping beside you has to get used to sleeping downhill too with this system!). Memory foam mattresses sometimes help to prevent you slipping further down the bed, and V-shaped pillows sometimes keep you in a better position.
Some people swear that none of these ideas make the slightest difference to them.
Sleeping positions are very personal and individual, and being able to get a good night's sleep, even after lots of trial and error, is definitely a prize worth going for.