[CPAP] New hose, higher AHI

[sleepyBuzz]

I have been successfully using my bi-level PR Dreamstation for over 18 months now (IPAP 20/EPAP 16). Although I had a rocky start during my first 3 months (AHI's as high as 12.5), my body/brain have settled down and according to Sleepyhead, my average AHI over the last year has been less than 2.

A week ago, I bought a new Respironics heated hose because my original one developed a leak. The old one works fine with a lot of duct tape, but the tape gets gummy after a cleaning soak in Dawn. With the new hose in place, my AHI has jumped to 3.5 - 4.52 with a significant increase in clear apneas. Also, the DreamMapper software has been reporting lousy mask fit for the same time period. I normally have 99-100% mask fit, but lately it's been in the low to mid 90%'s.

Just to make sure my symptoms were related to the new hose, I swapped back my old hose, duct tape and all, and the next two nights, my AHIs were 0.71 and 1.71, and my mask fit was back to 100%. Switched to the new hose one more time last night and recorded a 3.8 AHI with 90% mask fit.

I hypothesized that maybe because the hose is new, I'm breathing in some chemical fumes that causes my brain to forget to breathe. However, I soaked the new hose in warm water and Dawn (my usual cleaning routine) yesterday and it did not help.

Has anyone else ever experienced this or have any idea what's going on?

[OpalRose]

I really can't explain that, but it would be interesting to see a screenshot of a night with the old hose and one with the new hose.  

[sleepyBuzz]

[attachment=8671][attachment=8672][attachment=8673]
Thanks for replying, OpalRose. I am posting 3 screenshots for you. The first is a typical night before the new hose, the second is with the new hose, and the last one is when I went back to my old hose.

[Sleeprider]

The weird part is that tidal volume and minute vent are significantly higher with the new hose vs before and after. There is no good reason for it, but that higher breathing rate, probably explains the increase in CA and perhaps other events. This could be all about sleep disruption for unknown reasons, but might be as simple as odor. In all three charts the inspiration/expiration times are inverse which suggest the machine is not properly timing thing like BiFlex. Leak rates are notable, but lowest with the new hose, and based on the unbalanced flow rate chart, I suspect mouth breathing on all charts.

[ardenum]

Isn't the new hose different diameter inside? Heated hoses are usually wider to accommodate for the heating coil. This would explain higher tidal volume.

I assume you turned off heated hose in the settings?

[sleepyBuzz]

Isn't the new hose different diameter inside? Heated hoses are usually wider to accommodate for the heating coil. This would explain higher tidal volume.

I assume you turned off heated hose in the settings?

Hi crowtor,
My replacement hose was also a heated hose of the same diameter.

But let me comment with an update...
After my last post in October, I decided to order a new heated hose and short elbow hose (that attaches to the mask) from my DME instead of Amazon (where I purchased the last one) and guess what? My stats are back to normal. Have stayed that way for the last 3 months. Also, my insurance picked up the total cost of the hoses. Mere coincidence?  I don't know but I've learned my lesson to stay with my DME or the list of approved suppliers on this board for replacement parts.