Are these OA events positional?

[Apnea Infant]

Normally when you see long periods of no events than see a cluster of them together that indicates a shift in position. Most often it would be the chin dropping down and cutting off the wind pipe. Some people use a u-shaped pillow or soft cervical collar to prevent the chin dropping down as a fix. Others use wheat chaff pillows to hold the heads in place.

I agree with walla2. It is really clear in those 2 clusters and it is my own experience that a neck collar dealt with the problem. I believe that is the case for a lot of us here. Might be useful to take a poll on this to settle the debate once and for all.

[Mogy]

If a person has a higher AHI in REM than in NREM you might see clusters off on on throughout the night. How would you distinguish these from positional clusters?

[Sleeprider]

REM sleep tends to produce higher frequency of  OA, however REM is normally dispersed through the night rather than one or two episodes well into the sleep session. REM is not a deep sleep stage. This image is typical for REM distribution through the night, and we can usually distinguish REM onset apnea from positional by whether the clusters match this pattern, or occur more randomly. (language is not english, but people still sleep the same.)

[Ron AKA]

If a person has a higher AHI in REM than in NREM you might see clusters off on on throughout the night. How would you distinguish these from positional clusters?

A similar question would be whether clusters of events could be caused by arousal from sleep. I certainly have seen clusters from wake up events, and when you look at them, I think they are falsely flagged. When you are half asleep it is not uncommon to essentially hold your breath. When the CPAP is in active treatment mode, it sees these kind of events as both CA's and OA's. Some call it sleep wake junk...