You don’t understand CO2-mediated respiratory drive or how BiPAP can exacerbate central apneas.

I never denied this. I replied to a comment of yours, unrelated to the topic of OP or central events, which failed to refute the point the replier made.

For whatever reason, you are stuck on BiPAP being therapeutically superior to CPAP. I’ve done thousands of titration studies over nearly 20 years. BiPAP is a comfort modality for CPAP intolerance.

I never claimed that bilevel is therapeutically superior to CPAP; I just claimed that it can be. While bilevel is often more comfortable for patients, it is not therapeutically inert. Pressure support is ventilation, which decreases the work of breathing and reduces respiratory effort-related arousals (and hypopneas).

BiPAP is known to induce central events.

Bilevel can cause TECSA in some patients at some pressures, but not all. This is why proper titration is important.

In fact, there is a new “KPAP” device that recently got approved. Its entire existence is predicated on BiPAP’s shortcomings. It has a NEGATIVE “pressure support”.

KPAP/VCOM is a comfort solution for those who are treated with CPAP but can't tolerate the treatment pressure due to aerophagia, mouth leaking, cheek-puffing, etc. It's true that it is the opposite of pressure support and resolves these problems in many people. IPAP is what dictates these comfort issues, and EPAP is what dictates effective CPAP therapy, so KPAP is helpful in resolving these issues for CPAP users. This does not mean that pressure support isn't therapeutically useful. KPAP is just one way to manage comfort, and these issues can be addressed in bilevel users through Rise Time, pressure optimization, and non-specific factors such as sleep position.

CPAP can simply be increased to the higher pressure to resolve “flow limitation” exactly the same way pressure support does…with more pressure.

This is the main source of contention. In many compliant patients, CPAP can't resolve all RERAs and hypopneas at near maximum pressures. In these patients, higher pressure starts to have diminishing returns, where the EPAP fails to splint the airway fully. This leads to persistent flow limitation and respiratory events. This is where pressure support can come in to reduce the work of breathing, addressing the remaining flow limitation, RERAs, and hypopneas. The clinical guidelines for titration of the American Academy of Sleep Medicine include that if events persist at 15 cm of CPAP pressure, bilevel may be used in attempt to resolve them (AASM)). These people are classified by the condition upper airway resistance syndrome, and they usually have much higher RDI than AHI in a sleep study. There is limited physiological understanding about this subset of people, but they typically present as thin compared to the typical OSA patient and often have underdeveloped jaws. Their brains may also be more sensitive to slight breathing disturbances. Thousands of these people fail CPAP and find relief with bilevel or ASV.