Rainout and SI (Vibratory Snore Index)

Over the weekend I stayed in a motel for one night. I brought the xPAP, of course. For whatever reason, the machine kept me at a very low pressure during my night in the hotel and I had a very low AHI.

But I had a very high (for me) SI - Vibratory Snore Index. Most nights I have SI of 5-8 - that night I had a 15. However, I also noticed that I had some rattling due to "rainout" which I've really never experienced before - I had to pour water out of the hose in the morning before I put the machine away and there was enough water to make a wet spot on the carpet. I once overfilled the humidifier and got a little water in the hose but this time I intentionally underfilled it since I knew I was gonna have to dump it in the morning.

Question is, could rattling water in the tube cause the Respironics Auto to register Snoring? Is that the sort of sound it might mistake for snoring?

I do have some VS events on other nights at those low pressures - and I was wondering if it had just detected more snoring because of the low pressures. But, it the events detected were more than likely sounds from the water, well...

If so, I would want to figure out what else I did that night and replicate it - as the numbers were just really, really good - and the only bad number in the bunch was the SI. First AHI under 10 (3.5), no non-responsive, and the lowest treatment pressures.

Yes, it is entirely possible.

The current Remstar (as I understand it) senses vibrations in the airflow, not sound.

Early AUTOs did sense snores by sound but the side effects were too much of a problem. Nowdays as I understand them, all modern AUTOs sense by airflow vibration.

To compound the issue of reliability of snore data, many others over the months have commented that their Remstar SI didn't seem to refelect their sleep accurately. In many cases, water in the tubes was probably the contributor.

Cheers

DSM