Can you use a CPAP machine with a Shabbos clock or it is still an issue b/c the machine is still recording the changes in your breathing patterns and breathing pressure and is raising or lowering the air pressure in accordance to your breathing patterns and breathing pressure minute by minute. So, is it an issue that you are causing the computer to be recording and changing circuits while sleeping or not?
There are poskim that have an issue with what you are saying and don’t allow it. Others however permit it under certain conditions. Please see the attached article to see the opinion of R’ M. Heineman shlit”a https://www.star-k.org/articles/kashrus-kurrents/620/insights-from-the-institute-winter-2010/