[Treatment] Unclassified Apneas

[Thomas P]

Can anyone tell me why I am getting unclassified apneas of 23.65 in the data below and -0- obstructive and -0- clear airway (centrals?)
I am copying the data below. I tried to do a screen shot several times and I'm just not computer savy enough to get it. This is a typical reading that I get.
The first is the daily data and the second is the detail.
ResMed S9
VPAP Adapt ASVModel 36037
PAP Mode: ASVAuto
Min EPAP 4.0 Max IPAP 25.0 PS 4.0-10.0 (cmH2O)
Date Sleep Wake Hours
12/23/2014 21:43:30 06:03:33 08:04:28
Large Leak 0.41%
Clear Airway 0.00
Obstructive 0.00
Unclassified Apnea 23.65
Hypopnea 9.16

CPAP Statistics
AHI 32.82 25.83 22.82 9.15 9.15
Obstructive Index 0.00 0.00 0.00 0.65 0.65
Hypopnea Index 9.16 8.93 9.77 3.95 3.95
Clear Airway Index 0.00 0.00 0.00 0.00 0.00
Leak Statistics
Average Leak Rate 3.82 7.06 7.45 7.86 7.86
90% Leak Rate 12.00 19.20 22.80 0.00 0.00
% of time above Leak Rate threshold 0.41% 6.18% 10.60% 3.48% 3.48%
Pressure Statistics
Average EPAP 14.12 13.63 13.08 12.96 12.96
Min EPAP 4.02 4.02 4.02 4.02 4.02
Max EPAP 15.00 15.00 15.00 15.00 15.00
Average IPAP 18.48 17.96 18.46 18.44 18.44
90% IPAP 24.76 24.56 24.86 0.00 0.00
Min IPAP 4.04 4.02 4.02 4.02 4.02
Max IPAP 25.00 25.00 25.00 25.00 25.00

Changes to Prescription Settings
First Last Days AHI FL Machine Pressure Relief Mode Pressure Settings
Fri Dec 12 2014 Tue Dec 23 2014 12 23.94 0.00 VPAP Adapt ASV (36037) None ASVAuto Min EPAP 4.0 Max IPAP 25.0 PS 4.0-10.0 (cmH2O)
Thu Sep 4 2014 Thu Dec 11 2014 99 6.25 0.00 VPAP Adapt ASV (36037) None ASVAuto Min EPAP 10.0 Max IPAP 30.0 PS 4.0-15.0 (cmH2O)

Machine Information
Brand Series Model First Use Last Use
ResMed S9 VPAP Adapt ASV (36037) 9/4/2014 12/23/2014
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[zonk]

Can anyone tell me why I am getting unclassified apneas of 23.65 in the data below and -0- obstructive and -0- clear airway (centrals?)

Hello Thomas P and welcome
Here is ResMed definition of "unknown apnea" http://www.resmed.com/content/dam/resmed...er_eng.pdf

• An unknown apnea is an apnea during which a leak higher than 30 L/min occurs, precluding accurate determination of whether the apnea is obstructive or central.

[trish6hundred]

Hi Thomas P,
WELCOME! to the forum.!
Hang in there for more answers to your questions and much success to you as you continue your CPAP therapy.

[Thomas P]

Thank you Zonk & Trish.
I wonder why my machine seems to be taking care of apneas it can recognize but not hypopneas. I am thinking that I go into some kind of relaxed mode of breathing which triggers the hypopneas in the data. Is that possible?

[DeepBreathing]

G'day Thomas

I have much the same machine you do. It doesn't differentiate between obstructive and central apneas, just lumps them in together. I see a lot of hypopneas when I first turn the machine on, during the ramp and before I'm asleep - I just treat those as false positives. I see very few hypopneas (and virtually no apneas) during actual sleep periods.

Do you see a clustering of hypopneas when you first mask up? It could be the same thing's happening to you.

[Thomas P]

Thanks very much Paul,
I checked my data and unfortunately few of the hypopneas are in the ramp/before sleep time.

[TyroneShoes]

...I wonder why my machine seems to be taking care of apneas it can recognize but not hypopneas...

OA events and CA events are easy to recognize; they stick out. If your machine is capable of it it can react quickly to either event because it recognizes them straight away.

Hypops are a little different, in that they resemble normal respiration, just at a lower volume. Since respiration changes throughout the night, the only way to identify them without throwing lots of false positive flags, is to compare the shallow breathing to normal breathing (breaths immediately surrounding the hypop). The machine alerts and thinks "uh-oh...possible hypop happening" but then it has to wait for normal breathing for a few breaths to have something current to compare it to, after which it makes its determination. By then it would make no sense to try to force a breath or raise pressure, because that boat has sailed.

But even when an OA or CA event happens, there is no "taking care" of that event on a normal XPAP. It ignores CAs because it can't do anything about that anyway, and if a CPAP, ignores everything. If an APAP, it raises the pressure a little bit to prevent further OAs.

But a ventilator-type machine can theoretically raise pressure dynamically like an APAP to treat further OAs, and force a breath for CAs. But it still uses the same technique to identify hypops, so it can't respond to them directly.

[Thomas P]

Tyrone, Thanks very much. Makes sense.