Do you have some way of posting an image of the sleep study report? If you have an image file you just left click on it and drag it into the body of a post.
Some of the terms you have uses are not familiar to me. AHI is standard and the 46.1 fits you in the severe apnea range. It would include all apnea types and hypopnea. Stage R AHGI is a term I do not recognize. Your event count does not make a lot of sense. Say that you slept for 6 hours and had 60 central apneas then the CAI (central apnea index, events per hour) would be 10 (60 divided by 10). However the obstructive index would only be 1. This would mean that the majority of the other events that make up the AHI would have to be hypopnea, and they have assumed they are obstructive in nature.
In any case, a CAI in the range of 10 is high, and cause for some concern. It is possible that some or perhaps many of the hypopnea events may be central in nature instead of the assumed obstructive.
You should get a copy of the sleep report and seek a second opinion on what it means. The issue is that standard obstructive apnea treatment using a CPAP or APAP is not very effective and can even aggravate central apnea.
Not a medical professional, but those are my thoughts based on what I know about it.
What follows is the main part of my sleep study:
Protocol: This sleep study included the recording and monitoring of frontal, central, and occipital EEG, EOG, EMG, ECG, respiratory effort and flow, snoring, pulse oximetry, and position. Video recordings were obtained as needed. A qualified technician continually monitored patient throughout the night. Data was digitally stored and tabulated using Alice 5 software. Sleep staging and respiratory events were scored manually using AASM standards.
Sleep Latency: The patient’s sleep onset latency after lights out was 22.5 minutes. The Stage R sleep latency from sleep onset was 110.0 minutes. Total Sleep Time: The total time in bed was 376.0 minutes with a total sleep time of 244.5 minutes. Sleep efficiency was 65.0 %.
Sleep Architecture: The patient had 41.0 minutes of Stage R for 16.8% of TST, 37.0 minutes of Stage N1 for 15.1% of TST, 166.5 minutes of Stage N2 for 68.1% of TST, and 0.0 minutes of Stage N3 for 0.0% of TST. The arousal index was 5.4 per hour of sleep.
Respiratory: The patient was observed to have had a total number of 188 apneas and hypopneas with an AHI index of 46.1 per hour during total sleep time. The Stage R AHI index was 55.6. The normal AHI index is less than 5 per hour. There were 10 obstructive apneas, 0 mixed apneas, 60 central apneas, 118 hypopneas (4% desaturation or greater), 0 central hypopneas, 0 obstructive hypopneas and 5 RERA’s. The total RDI (A/H + RERA’s) was 47.4. Mild snoring was noted for 28.6% of TST. A split-night was not conducted due to physician order stating PSG.
Oxygenation: The patient had an average oxygen saturation of 95%. The minimum oxygen level was 83%. *Masimo Pulse Oximeters are accurate to a low SpO2 of 70% (+,-3).
Cardiac: The average heart rate was 55.6 beats per minute. The patient had a normal sinus rhythm with no arrhythmias noted.
Other/EMG: Patient had evidence of periodic leg movements during sleep. Patient had a total of 93 PLM’s with a PLM index of 22.8 and a total of 14 PLM arousals with a PLM arousal index of 3.4 per hour of sleep.
Diagnosis: Severe obstructive sleep apnea (G47.33) with an overall AHI of 46. Nocturnal hypoxia (G47.36). Abnormal sleep architecture with evidence of reduced of delta sleep. Patient did not qualify for split night (CPAP trial) protocol. There were significant periodic limb movements (G47.61) with a PLM index of 23.
Recommendations: Treatment for Obstructive Sleep Apnea is indicated to prevent cardiovascular morbidity and effects on daytime performance. Treatment options include CPAP/BiPAP, dental sleep appliances, upper airway surgery and neuro-stimulation. Until successful treatment has been established patient should be advised of the risk of driving or operating heavy machinery. Conservative therapy may also be helpful including weight loss, avoiding alcohol or sedatives prior to sleep, cool and totally dark bedroom, and trying to maintain a regular sleep pattern. Patient should return for a full night CPAP/BiPAP titration to optimize pressure settings if patient elects to have PAP therapy. Auto-PAP device set at 6-20 cwp should be considered while awaiting definitive titration or as an alternative to CPAP. Further evaluation and treatment of Periodic Limb Movements should be considered if they continue to cause arousals despite successful treatment of the obstructive component of the patients sleep disorder.
That is a fairly clear explanation. The key numbers are:
Sleep time: 244.5 minutes, or 4.08 hours.
Apnea events and the events per hour index:
Obstructive apneas: 10 , OAI: 2.45
Central apneas: 60, CAI: 14.7
Hypopneas: 118, HI: 28.9
They said 0 obstructive hypopneas, and 0 central apneas. However, they kind of have to be one or the other. Probably what this really means is they did not classify the 118 apneas. It probably has to be done manually and they didn't do it.
What does this mean? I would be concerned about the high central apnea component, and that it might go up with CPAP or APAP treatment due to the pressure used. If you go ahead with the titration test they are recommending, it should be very telling. They may find that when pressure is increased then the central apnea may increase, and if those hypopneas are central in nature, they may increase too, or not decrease. I would go ahead with the titration test, and then question them very carefully about the results, and/or get a second opinion. You do have a condition that needs attention and treatment, but it is not totally clear what is the best way at this point. There are ASV machines that are more appropriate for treatment when central apnea is the dominant component of a high AHI. Something to discuss when you get your titration results.
Curious that neither the sleep tech or my doctor observed that the dominant component of my high AHI was central apneas. Makes me think they don't know what the bleep they are doing.
Heaven forbid that a patient who knows nothing about reading these results would have to point this out to them.
Since they already ordered me an APAP, I'm wondering if that would help me diagnose central apneas, or not.
Well the general assumption is that all hypopnea is obstructive in nature, even though very few labs actually verify that. And in most cases that assumption is correct. The CAI of 14.7 should have been a red flag to them however.
Yes, providing they are prescribing a good APAP like the ResMed AirSense 10 AutoSet, it will report central apnea frequency. However, you will have to ask them to set it up with the enhanced sleep report menu. The other option is to view your results in SleepyHead. The Respironics Dreamstation Auto should be similar. To my knowledge the Fisher & Paykel SleepStyle machine does not identify central apnea so you will want to avoid that one.
I hope you have an arrangement to return the machine if it does not work for you. If central apnea turns out to be a significant problem then it probably won't.
FWIW, my sleep study (a home test) indicated a preponderance of central events too with similarly high AHI results.
As soon as I started therapy however my numbers dropped into the "normal" range (5 or <) almost immediately and even though CAs continue to be my "wildcard", and I occasionally have a poor night (still even then never over say a total AHI of around 6), my averages over the past 3 months on my current machine are CA: 1.2, OA: 0.8 and overall AHI (including "other"/hypopneas) is 2.4. Suggest you give it all a chance, do the therapy, read all you can, exchange ideas on sites like this (e.g. with folks like Sierra who's input I have found particularly helpful), and follow your instincts to tweak your therapy accordingly.
I will go ahead with the APAP (not sure which one I will get yet) and I will keep an open mind and see how much it helps me. I will be sure to ask about returning the APAP if it turns out an ASV is more appropriate for my condition.
All of you have been incredibly helpful and I appreciate your responses so much!
Just make sure the APAP can distinguish between obstructive and central apnea, and report on the proportion of each.
I requested the doctor write the script for a ResMed APAP. That would be the Airsense one, which does have that capability. Now whether my crappy insurance is able to deliver on that is another matter.
My first choice would be a ResMed AirSense 10 AutoSet For Her. The For Her version includes an extra algorithm that is suitable for lower obstructive apnea and higher hypopnea. It is only a setup option, so you can use it, or use the standard algorithm. The Dreamstation would be a second choice. About the only feature it lacks is the ability to use EPR on ramp only, like the ResMed does.
The really poor choice would be the Fisher and Paykel machine. It does not distinguish between centrals and obstructive apnea, and increases pressure to both. The ResMed and Dreamstation ignore centrals, but report them.
My diagnosis was mild obstructive, AHI of 8. 28 hypopneas and 18(?) central apneas. I went with an Apap and find my numbers are now generally under an AHI of 2. Typically between 1 and 1.5 with most of them being central in nature. My pressure is rarely over 6 or 7 which probably helps to minimize more centrals being brought about.
I don’t feel any more well rested than before but that’s another matter.
With respect to the centrals, the neurologist I’m seeing is also a sleep doctor. He explained to me that sometimes the centrals are more to do with sleep and wake transitions than with a true central apnea related to heart or brain stem issues. The more sleep disturbances you are having due to hypopneas or obstructive apneas (or even non sleep disorder awakenings) the more opportunity for central apneas to occur. I’d not be afraid to try an apap, particularly if you can exchange it for a different machine if you wind up needing something more advanced. Sierra suggested this to me and it worked well in my case.
It's worth remembering that events which appear to be (and are therefore scored as) central events on a diagnostic study are not necessarily central. Also, it is indeed possible, although unusual, for central events to be treated by CPAP. So there is a very sensible and well-established protocol to try CPAP as a first step in treatment regardless of how the diagnostic study looks. This is the best way of being certain if they really are central events, and can also yield some data that is very useful in applying BiPAP to treat central apnoea. Of course, this is best done in a lab, where someone is watching and can swap to an appropriate Bi-level therapy if CPAP is ineffective and there are clear central events. It can also be done by trying CPAP at home, but this is much slower. In your case I noted that there is an increase in you AHI when you are in REM. This is strongly indicative of obstructive apnoea and not central. I would suggest that your physician and technicians might know what they are doing and are following the appropriate protocol. The real test will be how they respond based on how well your treatment works.
The Auto CPAP has been unable to even come close to getting my AHI under 5. The Central Apnea component is especially out of control. Over the last 11 days my AHI is averaging around 20 and my Central Apneas are about 5 times more than the obstructive ones.
Do I need an ASV? And if so how do I justify it to my doctor and insurance?
Complex (both central and obstructive but with central dominant) sleep apnea is difficult to deal with. Here is a link to a good discussion about Complex Sleep Apnea. An ASV is a probable solution providing you do not need more than 20 cm of pressure to deal with obstructive apnea. They are expensive if insurance is not covering it though.
Are you using SleepyHead to monitor your apnea? If not it would be a good idea to get a better understanding of what is going on. An APAP can aggravate central apnea. Even when the machine does not increase pressure to a central apnea, it may respond to a central hypopnea because no machine that I am aware of can distinguish between a central and obstructive hypopnea. About the only way of dealing with it is to limit maximum pressure to the level required to deal with obstructive apnea and no more. You could also try with and without EPR.
Insurance companies can be difficult. To date the APAP has not worked, so that is the first step. Next they may insist on a BiLevel machine which does have a bit more capability, but in most cases it cannot deal with central apnea very well either. You may want to think of it as step you have to go through to get them to approve the ASV.
The other thing to check out with your doctor and heart specialist are other issues. Some heart issues can cause central apnea, and some drugs as well. If you live at high altitude that can aggravate central apnea as well.
Keep in mind that if they cannot get total AHI under 5 the treatment is not successful.
Hope that helps some,