Over the last two weeks I have been using a chin strap (Carefusion ruby adjustable) and while it can deliver some great numbers (super low AHI and low leaks) I have been finding its "adjustability" slightly frustrating. One night I might have it a little too loose and the leak numbers suffer while another night I will adjust it such that I awake with great numbers but a bit of a headache (that rapidly dissapears). I believe the headache is due to the strap being too tight.
The strap has an adjustment point at the top and lower back of the head. I have found since you cannot see how it sits (when putting on in bed) its not only the widths on the velcro attachments but also the angle you install it. With seemingly infinite variability I was wondering if others that use a chin strap have a method to limit night-to-night variation once they have locked in a good setting. Anyone?
Really I would like a chin strap with an indexing to the rear velcro (as this is the daily change) and also the angle.
Also, with the leaks, given I am using a Airset 10 and 24L/min or so it the large leak boundary, what is the maximum acceptable leakage (% time over leak redline) for effective treatment? At worst my leaks (prior to strap) were 1-4% in the large leak territory but I seemed to really feel it the next day.