Wife tried machine, lots of flow limitations?!

[YouTakeMyBreathAway]

Hey everyone,

I just got my new BiPap machine so my wife gave my Airsense 11 a shot (she's tired during the day, but not diagnosed).

She was struggling to keep the machine on the entire night, but while she had it on, she had consistent flow limitations and the machine just kept cranking the pressure to max ~immediately, so I set the maximum to 8.0.

What could be the reason that her flow limitations are through the roof? She has worn my pulse oximeter before, too, and her oxygen does remain at 97-98% throughout.

Flow limitation median: 0.03
Flow limitation p95: 0.19
Flow limitation p99: 0.33

   

[Sleeprider]

Did she sleep, or is this all awake? We need to zoom in on the respiratory flow to see what is going on, but flow limitation can be nasal, upper airway and can even be influenced by mask fit if the nasal pillows are too small.

[Nightynite]

That data looks insufficient to me. Looks like she fought with her equipment most of the time.

[YouTakeMyBreathAway]

Yes, she was asleep while wearing the mask.

It does look like the flow limitations may be higher when awake / while falling asleep than when asleep. In this segment she mentioned falling asleep within ~10 minutes, which is roughly when the flow limitations reduce.

   

Here's a zoomed in version:

   

[Sleeprider]

Based on the zoomed image, inspiration/expiration times are normal, and your wife works at a breath until it satisfies her needs. I do not see frequent arousals or recovery breathing in any of the graphs. She may be very adapted to the more difficult inspiratory flow effort, that is certainly there. I think without a professional assessment, chronic inspiratory flow limitation without apparent arousal is something that deserves further evaluation of her upper airway by an ENT or evaluation by polysomnography in a sleep test. While flow limitation is there, and pressure support would likely help, I'm not in a position to either diagnose the problem (if any) or recommend anything based on this home experiment with CPAP. It's there, and it's classic flow limitation, and that's all I have. If continuing to look at this, set minimum pressure at 7.0 to fully access the available EPR, and maximum at a comfortable tolerated pressure. With this much flow limitation, the Autoset will always seek the highest pressure in the set range and will stay there. If your wife feels tired,or chronically snores, a sleep study may be in order. The screening with CPAP shows no events, so she apparently maintains respiratory volume and rate in spite of the upper airway restriction.

[YouTakeMyBreathAway]

My wife did an in-lab sleep study, here’s the results, any thoughts?

—

SLEEP SCORING DATA:
Lights Out / On (clock times): Out : 22:23:20 / On: 06:01:11 Total Recording Time (TRT) (min): 458 minutes
Total Sleep Time (TST) (min): 297 minutes
Sleep Efficiency: 64.8
Sleep Latency (min): 68 minutes
Stage REM Latency (min): 59 minutes
Wake after sleep onset (WASO) (min): 93 minutes
Stage N1 Sleep (min, % of TST): 4.4 % Stage N2 Sleep (min, % of TST): 57.6 % Stage N3 Sleep (min, % of TST): 15.7 % Stage R Sleep (min, % of TST): 22.4 % Supine Sleep (min): 39.5 minutes Arousals (index, #): 11.9 events/hr
RESPIRATORY ANALYSIS:
Apnea/Hypopnea Index (AHI): 8.3 events/hr
AHI (AHI /w Hypopnea events 4% desat or greater): 0.0 events/hr NREM AHI: 4.7 events/hr
REM AHI: 20.8 events/hr
Non-Supine AHI: 8.2 events/hr
Supine AHI: 9.1 events/hr
Respiratory Disturbance Index (RDI): 8.7 events/hr NREM RDI: 4.9 events/hr
REM RDI: 21.7 events/hr
Apneas (index, #): 0.0 events/hr Obstructive Apneas (index, #): 0.0 events/hr Mixed Apneas (index, #): 0.0 events/hr Central Apneas (index, #): 0.0 events/hr Hypopneas (index, #): 8.3 events/hr
RERAs (index, #): 0.4 events/hr
Mean Wake SpO2: 97.0 %
Mean Sleep SpO2: 97.0 %
Minimum Sleep SpO2: 96.0 %
Sleep Time with SpO2 < 88% (min, % of TST): 0.0 minutes - 0.0 %Cheyne Stokes breathing: No Snoring: Mild
CARDIAC ANALYSIS: Mean Awake HR: 73 bpm Mean Sleep HR: 70 bpm Highest Sleep HR: 91 bpm
Bradycardia: No
Asystole: No
Sinus tachycardia: No
Narrow Complex Tachycardia: No Wide Complex Tachycardia: No Atrial Fibrillation: No
Other: None
LIMB MOVEMENT ANALYSIS:
Periodic Limb Movements of sleep (PLMS) (index, #): 5.9 events/hr PLMS with arousals (index, #): 2.8 events/hr
OTHER ABNORMALITIES:
No other unusual body movements were demonstrated and no seizure activity was noted.
-------------------------------------------------------------------------------- CLINICAL INTERPRETATION:
1. Polysomnographic findings are consistent with mild Obstructive Sleep Apnea. The overall RDI was 8.7 events per hour of sleep and the AHI was 8.3 events per hour (*AHI 4% or greater: 0.0). The lowest oxygen saturation was 96.0.
2. Mild snoring was present per the technician's notes.
3. Periodic limb movements of sleep were not significant.
4. A single lead ECG was monitored throughout the study, and did not reveal any cardiac issues.
5. The most efficacious treatment modality for sleep apnea is continuous positive airway pressure (CPAP) and surgical treatment modalities are alternative options. An oral appliance may be effective treatment in mild cases. Non-specific treatment options include weight loss of at least 10% of body weight (if overweight), avoidance of supine posture (i.e. side- sleeping or elevation of the head 30 degrees is preferred), and avoidance of sleep deprivation, alcohol and nicotine.

[Sleeprider]

No change in assessment from my first post. Try to ge a Resmed Autoset and use minimum pressure 7.0 and maximum pressure 12 with EPR 3. Should resolve most issues. C

[Gideon]

+1 to Sleepriders suggestions

[YouTakeMyBreathAway]

OK this took a while, but my wife was finally able to use the Resmed AirSense 11 AutoSet. It does appear that most flow limitations are gone. Any recommendations on further fine-tuning?



She first tried the N30i mask but mentioned both that she sometimes woke up feeling like she couldn't breathe and also that the woke up from mouth leaks, so now she is using the F20 which seems to be working better.

[Sleeprider]

Efficacy looks great at these settings and based on this chart there is no need for changes. Looks a lot better that what we saw back in November. Pressure changes are minimal and as you note, flow limitation has resolved. I would call this good and leave it alone unless she has a specific complaint or things change.