My daughter's sleep study results states significant central & obstructive events occurred.
I know what each are (basically) but what exactly does the interpreter see where he is able to differentiate between OSA & CSA events?

The study report also states:
Events appeared to be both obstructive and central in nature (the latter being REM associated hypopneas which may be physiologic rather than pathological)
How exactly would CSA be physiologic rather than pathologic?

Thanks,

Jen

Jen-

I am not a sleep professional or a medical professional and most of the information I have run across has to do with apnea and sleep problems in adults rather than in children. While I have some confidence in what I am about to say, I do urge you to check these questions with your child's doctor.

Basically, as you already know, obstructive apnea occurs when there is a normal attempt at breathing and airflow to the lungs is interrupted either to a significant extent (in the case of an hypopnea event) or in whole (in the case of an apnea event). In central apnea, by contrast, there is significantly reduced or absent attempt to breath with a resulting interruption of airflow to the lungs. In a sleep study, the interpreter scores an event as either an obstructive event or a central event based on whether there is a normal attempt to breath or not during an apnea or an hypopnea. (I am deliberately leaving out mixed events which combine elements of both obstructive and central events). I believe the distinction is made based on some of the sensors used in the sleep study which monitor movements in the chest and abdomen. Although the difference between central and obstructive events may seem straightforward, in practice the distinction may be more difficult to make. Many sleep labs do not seem to make an attempt to differentiate between central hypopneas and obstructive hypopneas, and I give your sleep doctor a lot of credit for trying to make this distinction.

I confess that I do not know what the interpreter of your daughter's sleep study had in mind when (s)he made the statement about her REM-associated hypopneas being possibly being more physiologic than pathologic. A possible interpretation might be that the interpreter believes that these hypopnea episodes may be related to your daughter's positioning during the REM portion of her sleep study, it could be that the interpreter might believe that your daughter did not breath as deeply during REM sleep (thus leading to increased hypopneas, during REM the body is normally rendered immobile and this may have compromised your daughter's normal breathing - although this is not usual), or it may be that the interpreter is trying to make some other distinction between events related to relatively weak chest and/or abdominal muscles (which are utilized in breathing) as opposed to central events that are directly due to disruption of the normal chain of events that trigger the body's normal ability to recognize the need to breath. Or the interpreter may have meant something different, although I believe that these are the three scenarios that seem most likely to me.

If one of the sleep techs who post here offer a different interpretation, I would be interested in hearing it and would glad acknowledge that they would be far more likely to be on target than me. In any case, I would also urge you to get the interpretation straight from the sleep doctor just to be sure that both of you share the same understanding.

Let us know what (s)he says and do keep us posted.

Good luck and best wishes to you and your daughter,

Bill