I was on a typical dose of Tramacet (1-2 pills every 4 hours as needed) and only taking usually 1 every 6-8 hrs and then 2 before sleep (to dull pain and help sleep). From my research Tramadol (the opioid ingredient in Tramacet) is less prone to respiration depression but without a doubt it was present as can be seen in the following three screenshots.
This first image shows how my respiration rate dropped from an average of 13.5 down to 10.5 on the 5 nights using Tramacet. The lowest my RR has been in nearly 1.5 years of CPAP use was 12 and it rarely drops below 13 so having RR drop consistently to 10-10.5 range seems somewhat significant. You can see that my tidal volume increased a bit higher (500 average is about as high as it ever is and I find it interesting how it kind of flatlined there) to make up for reduced RR and my minute ventilation was slightly lower than usual (5-5.5 vs average around 6).
This second image shows a typical night while on this medication. Note most of the the flagged events are user flag 2 which is a 50% reduction over 6 seconds. For me this index is in the 2-5 range most nights but it averaged just under 20 during these 5 nights on Tramacet.
This third image shows an example of the typical events. You can see how the duration between exhalation and inhalation is extended. In all of the user flag 2 events this means that the Resmed autoset started sending pulse wave to see if current lack of flow was central or obstructive in nature and since you can see return wave form in air flow you can tell that it was central in nature as expected. In this specific example the one instance was very close to being flagged a central apnea (just under 10 seconds long).
Anyways I just thought it was neat to notice this and figured I would share for others interest/knowledge of what this can look like on OSCAR. It is something good to know about and keep an eye out for if starting a new medication known to potentially depress respiration (opioids, benzodiazepines, alcohol etc). In my case I only needed the medication short term otherwise I would be asking my doctor for an alternative.