Sierra

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.

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.

This is ResMed's Automatic (AutoSet) CPAP machine, or APAP. They really only make two. One is the standard AirSense 10 AutoSet, and the other is the AirSense 10 AutoSet For Her. With the automatic machine, you set the minimum and maximum pressure supplied on inhale (IPAP). During the night the machine raises and lowers this pressure to address obstructive apnea and hypopnea events. It ignores central apnea events.

A CPAP machine uses a fixed inhale or IPAP pressure, and does not adjust during the night.

A BiPAP machine have different flavours, but most are similar to an APAP, but they allow you to set both inhale (IPAP) and exhale (EPAP) pressures. And they allow the difference between the two pressures to be quite high. This can be used to assist breathing. Last they usually have a maximum pressure of 25 cm, instead of 20 cm like a regular APAP.

EPR or expiratory pressure relief is a ResMed term and feature. It reduces the exhale pressure by a set amount of 0, 1, 2, or 3 cm. Yes, this does essentially the same thing as a BiPAP machine that has a differential in IPAP and EPAP of the same set amount. EPR can be found on both APAP and CPAP machines.

But to get to the question you may be really asking, is which machine is appropriate for central apnea? My thoughts are that the first approach to central apnea is to minimize pressure, as pressure often aggravates the incidence of central apnea. To do that you want to avoid any differential between IPAP and EPAP, or avoid EPR. For that approach a CPAP with a fixed pressure can often get the best result, although an APAP can be adjusted to do nearly the same thing.

So why do you hear about BiPAP machines being used for central apnea? Good question that is difficult to answer. For the minimizing pressure approach they offer no advantage. However, they often have features that can detect that the person is not trying to breathe (central apnea), and then automatically cycle the inhale and exhale pressure by a large amount to help them breathe. When they are of that type and set up that way, they can help central apnea to some degree. However the machine that is best suited to addressing central apnea if it cannot be controlled to acceptable values (<5 AHI) is the ASV machine. It follows each breath and adjusts pressure on a breath by breath basis to maintain breathing. They are fairly expensive ($4000 or so) and carry some risks in using them.

Hope that helps some,

It is not uncommon for there to be apnea events when you are just waking up or going back to sleep. Some call this Sleep Wake Junk and dismiss it as noise. The CPAP machines generally do not start counting apnea events until after the ramp period is over, and at least in theory you are asleep. This is to avoid reporting noise and inflating the AHI number. On the EPR I will see if I can find the existing thread on the subject and bring it back for discussion.

Edit: I found the thread on EPR but it is closed for comments. However, here it is. It should give you more views on EPR than you really want to hear!

https://myapnea.org/forum/not-understand-epr-setting/1#comment-17050

It is always a good sign to see no central apneas in the sleep study. It does not totally eliminate the possibility that you will have them when under CPAP pressure, but it sure improves the chances that they will not be a problem for you.

When do you get your machine? Will they set it up for you?

It seems to me that sleep apnea and oxygen desaturation events are just two different ways of measuring the same issue. When you stop breathing then oxygen goes down. In the UK mild (5-15 AHI) does not qualify you for CPAP treatment. I guess the thinking is that it is not serious enough to treat. In North America it is more likely to be treated, as most insurance companies will pay if AHI is over 5.

It is far simpler to cut to the chase and just turn EPR off when sleeping. No math needed. There is a reason that ResMed has that option to do EPR on ramp only. When you are awake it makes sense, and when you are sleeping it does not. And there is a reason that F&P resisted offering an EPR setting until very recently with their last model.

Actually my suggestions have nothing to do with central apnea. The purpose of discontinuing EPR during sleep is to reduce the frequency of obstructive apnea. They are as likely to occur during exhale or the inhale/exhale transition, so using EPR reduces the effectiveness of the pressure which is preventing obstructive apnea. The reduced pressure also improves comfort.

And you do not have to do any calculations at to where to set EPR. Just set it at 3 cm. The machine will not go below 4 cm in any case. It self adjusts.

I have never really liked using a snorkel mask. It always seems like it is restricting my air flow more than I like. When I first started using a APAP I was quite apprehensive. My machine was probably not set up as well as it should, and certainly not the way I would set it up today.

The main mistake that many new users make, and many professionals that set up machine is to start with a pressure that is too low. Out of the box the machine is set up to deliver a minimum of 4 cm of pressure, and a maximum of 20 cm. Many just get handed the machine and told to go for it. The reality is that 4 cm of pressure is too low, and for the majority of people it will feel like the mask is restricting the air flow (like the snorkel mask feeling).

What one really needs to do is get comfortable with the mask while sitting up and watching TV or something. After you feel reasonably comfortable then increase the minimum pressure 1 cm at a time and breathe in deeply. At some point it will start to feel like there is no restriction at all when you breathe in. That is a good minimum start pressure to use if it is reasonable -- probably in the 6-8 cm range. The second most important thing is to turn the Expiratory Pressure Relief (EPR) on and set it at 3 cm. This will reduce the pressure on exhale by up to 3 cm. It cannot reduce it below the 4 cm minimum of the machine. So for example if your minimum start pressure is 7 cm, it will reduce to 4 cm on each exhale and then increase to 7 cm on each inhale. Most find that very comfortable with it easy to inhale and exhale. The third step is to set the EPR to be on only during the Ramp because that reduction to 4 cm during sleep can promote apnea, which in turn will initiate a pressure increase by the machine. The automatic set pressure can be kept lowest if the EPR is automatically shut off when you are sleeping. Last the Ramp type should be set to Automatic. This way the 7 cm and 4 cm pressure cycling will be held at those pressures until the machine decides you are asleep. Then it will increase the pressure to the minimum automatic set pressure point (if it is higher than 7 cm). Reduction of the pressure on exhale will stop.

When set up this way, I find the mask very comfortable for going to sleep. It feels like you are wearing no mask at all, from an airflow and pressure point of view. Before I set it up that way, it was not so comfortable and I got frustrated when trying to go to sleep. Another trick is to use the user menu to start the humidifier prewarming about 15 minutes before you go to bed. This warms up the water so you will get the set humidity right from the start. Not essential but more comfortable.

An important point is not to put the mask on and jump into bed the first night. Spend some time with the mask during the day while watching TV or reading and just make friends with the mask. Adjust it until it is comfortable fitting and not leaking.

Hope that helps some. If you want a checklist in order of the items in the setup menu let me know, and I will give you my suggestions.

The standard objective is to be under 5 for AHI. With central apnea as an issue I have a bit of trouble always doing that. My wife on the other had who has almost no central apnea, is usually under 1.0 for AHI.