Crazy High AHI's : is it even possible?

[drjeff2267]

I use a ResMed S9 autoset set at a pressure range of 7-16. I use a Fisher and Paykel Flexifit 431 mask. I have had sleep apnea treated with CPAP for 3-4 years. Usually my AHI is in the 3-5 range with an average pressure of 10. Over the last month I have seen a run of very high AHI's. The highest has been 144 but most have been over 100 for almost 2-3 weeks. I thought my machine was malfunctioning and switched to an S8 autoset I use as a spare and for traveling and the AHI numbers were the same.I am not waking any more sleepy than average. I have been using narcotic pain relievers since I have had recent neck surgery so naturally I thought of central sleep apnea. But, again, the AHI's are so high. Is it even possible?

[n0hardmask]

Dr Jeff,
I'll ask some diagnostic questions that will help the next folks to be more specific. My gut answer is there's something squirly, like it's reporting a handful of events in a very short period of time, hence a steep AHI.

Do you use software to get these numbers, or are you going by the LCD ?

If you're using Sleepyhead or Resscan, what is the breakout of events for, say first three hours, second 3, and final (third of night)? I'm asking for raw numbers of OA, CA, HA, etc.. for the three periods.

You say you aren't waking up, but is your sleep consistent, or is (like mine) very inconsistent, with clusters of events scattered through the night?

What are your leaks like? Any change from a month ago?

Hopefully you can provide some of this info; and if you look up posting screenshots of the computer graphs, you can post some shots of your Resp Rate, Pressure, etc. Others will come along and have more input.

[drjeff2267]

Seeing pulmonologist tomorrow. Will report back. Majority of events after AHI jumped up were clear airway events or unspecified apnea. My obstructive numbers have remained stable. Without going into further detail, I think the narcotics are the culprit.

[Todzo]

Talk with your doctors about [1,2].

[1]: Gilmartin G, McGeehan B, Vigneault K, Daly RW, Manento M, Weiss JW, Thomas RJ.
Treatment of positive airway pressure treatment-associated respiratory instability with enhanced expiratory rebreathing space (EERS).
Source: J Clin Sleep Med. 2010 Dec 15;6(6):529-38. Division of Pulmonary, Critical Care and Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA.
Link: http://www.ncbi.nlm.nih.gov/pubmed/21206741

[2]: Dynamic CO2 therapy in periodic breathing: a modeling study to determine optimal timing and dosage regimes
Yoseph Mebrate, Keith Willson, Charlotte H. Manisty, Resham Baruah, Jamil Mayet, Alun D. Hughes, Kim H. Parker and Darrel P. Francis
J Appl Physiol 107:696-706, 2009. First published 23 July 2009; doi: 10.1152/japplphysiol.90308.2008
Link: http://www.ncbi.nlm.nih.gov/pubmed/19628721