How low is too low SpO2 during an event?

[MyronH]

My AHI is fairly controlled. I usually have AHI < 2 on good nights. My concern is even on good nights, my SpO2 will dip quite suddenly to lower 80%'s with a short 20-45 second OA.

The other night I had one 20 second OA that dipped to 80%. The only reason it was only 20 seconds long was my Contec O2 sensor alarm woke me up. Maybe it could have dipped further? 

I woke up with my left side of chest over my heart shaking/quivering. I thought maybe I was in afib but wasn't fast enough to use my Kardia device to check. This shaking occurs occasionally on nights when my O2 drops. This shaking and low oxygen has happened in the past and caused me to have major nights sweats and to go into AFIB last year.

I think these major drops are causing strain on my body and I want to do something to control them. I am scared to not wear my oxygen sensor now at night.

My sleep doctor doesn't seem concerned. Is dropping to 80% or even lower, normal for people with sleep apnea? How low can it go and will low oxygen always wake me up to start breathing again? Can I Ditch the oxygen sensor?

[Mosquitobait]

Talk to your cardiologist. They would be more in the know considering you have had AFIB.

[OpalRose]

MyronH,
Being that you also suffer with AFIB, this is a serious concern to bring up to your Cardiologist.
Forget your sleep doctor.

From everything I’ve read on Oxygen levels during sleep, a drop that falls below 88% for a long period of time should be a real concern, and brought to the attention (in your case, since you have AFIB) of a Cardiologist.

Have you and your doctor discussed using supplemental Oxygen? He/She could order an overnight oximentry test in your home.

Your Sleep Apnea appears well controlled with an AHI <2.

[MyronH]

My sleep doctor said I didn't need oxygen. And he ordered an overnight SpO2 monitor. But that night I wore it, I didn't have any events that lowered my oxygen to the 80's so he said all looked good. I wore both his and mine monitors and my Contec was pretty much accurate with his.

I don't think I qualify for supplemental oxygen. Because I barely qualified for a ResMed Air Curve and he said I didn't need one with backup rate. He said backup rate models were outdated and I'd have to go to ASV which is something I'm not qualified for.

I have appts next week with my cardiologist and electrophysiologist so I'll talk to them. I'm also planning to get another opinion from a another sleep doctor next week.

The issue is that most nights I'm okay. I can sometimes have a 30-45 second OA and my oxygen level stays above 88%. It will sometimes never drop from the 90's. But other times I have a short 20 sec OA, it drops like a stone to the 80's. Doesn't make sense to me!

[mesenteria]

In my experience, if you feel a flutter in your mostly-left chest as you lie on your left side, there are two high probabilities, and I would list them in this order of likelihood:

a. Bowel gas.  When you look at diagrammes of the bowel, it rises from the mess it surrounds in the abdominal cavity and ascends to run transversely under the stomach and liver. It descends on the left side to the rectum.  Lying on the left side is the 'recovery' position in which you will be placed when they wheel you out of the colonoscopy lab.  That's so that you can break wind to your little rectum's content...which it will do....with alacrity, and often.  Been there.  Point is, bowel gas makes thing shake and quiver as it gets moved or propels itself into gaps here and there around digested food.  Most often I will break wind soon after that sensation.  Statistically, it's quite reliable that way; or,

b. Genuine fibrillation.  When you awaken with a start, you will naturally, and quickly, secrete epinephrine into your blood.  That's the panic chemical that raises your body hair to make you look larger and more formidable (great for cavemen, not so great for homo-sapiens, especially our women), elevates your heart rate, makes you sweat more to cool you while you run hard for ten minutes in a panic, or prepare to wrestle a beast to save yourself, and it makes your diaphragm work overtime forcing you to take in huge lungsful of air for the same reason just cited.  In my case, fibrillation does come on with a sense of panic, alarm, or general stress when I think of looming problems.

If you were to wear a Fitbit, or in my case a Samsung Gear wristwatch, they have the capability to measure your pulse.  Mine, the Gear, also shows the sinus rhythm pattern.  When I had my first definitive AFib episode 16 months ago, my watch showed a dense vertical squiggle and eventually said, "Clean sensor, cannot read pulse."  A nearby blood pressure monitor that I reached for showed that my pulse was 150....at rest.  I mention this because some devices will give a good indication of AFib, and many of us wear such devices to bed so that the quality and duration of our sleep can be monitored.  About an hour after rising, my Gear buzzes and the screen shows my 'Sleep Record', and the corresponding app on my smart phone will show the episodes of light and deep sleep with different blocks of shading.

Some thoughts...

[Mosquitobait]

What your cardiologist does depends on his concerns. My doc has me wear my Sp02 monitor 3 days every month. I don't have to actually GIVE him anything, but just let him know if there are any changes. If there are changes that are not explainable, then he will send me off to the cardiologist with my data. My Mom does her blood pressure regularly for a similar reason. They already know she has a heart problem and they want her to use her home machine and report if there are changes - either sudden or trending. The last time she got a Holter monitor for 3 days, confirming exactly what the home blood pressure machine had been shrieking about. So, given that, I would continue doing your testing so that you can report to your cardiologist what your findings are.

[MyronH]

What your cardiologist does depends on his concerns.  My doc has me wear my Sp02 monitor 3 days every month.  I don't have to actually GIVE him anything, but just let him know if there are any changes.  If there are changes that are not explainable, then he will send me off to the cardiologist with my data.  My Mom does her blood pressure regularly for a similar reason.  They already know she has a heart problem and they want her to use her home machine and report if there are changes - either sudden or trending.  The last time she got a Holter monitor for 3 days, confirming exactly what the home blood pressure machine had been shrieking about.  So, given that, I would continue doing your testing so that you can report to your cardiologist what your findings are.

So what about the other days of the month? You may have long CA's or something that causes low oxygen dips the other days of the month.

Take a look at last night. I've been doing great now, since using a cervical collar to hold my head. But I still get a random CA/OA that causes oxygen dip, and my HR to race at 100bpm+. I had my Contec sensor set to 87%. If it was set lower then that, I'm wondering how long the apnea would have lasted. Low 80's is pretty low, even for one short apnea, and can cause my heart to go into AFIB, just like obstructions. Yet my sleep doctor doesn't care. My cardiologist doesn't care. My Electrophysiologist also doesn't care.

I mean, if I were to turn off the alarm, so it wouldn't wake me up, would oxygen drop even lower and the apnea last longer? That is my concern, that my body won't wake me up to breathe again. I videotaped myself last night again, and during this episode, my body just laid there, not breathing for 30+ seconds, which is why my heart went to 100+bpm!