My Sleep Apnea: CPAP

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In previous entries, I've talked about my initial adventure with sleep apnea and my subsequent sleep study. The gist of those entries is that I was diagnosed with "severe" obstructive sleep apnea, with an AHI (Apnea-Hypopnea Index) of 48. This number means I had an average of 48 sleep interruption "events" per hour -- these events range from blood-oxygen desaturation to a complete closure of the airway. There are lots of people out there with worse cases than mine (including readers of this blog!), so I took some comfort that my case seemed pretty typical -- there was every indication that I could be treated.

In my daily life, particularly in the last few years, I've been a very sleepy person. I've generally existed in a sort of brain fog, muddling my way through each day until I could collapse for a longish night's sleep (10+ hours) that, sadly, didn't seem to refresh me. Of course, now I realize that during all that sleep, I was having these constant breathing interruptions, which caused my blood pressure to increase, and severely impaired my ability to experience the restorative effects of sleep. It's strange to think that sleeping doesn't lead to restfulness, but it certainly explained why I just seemed to feel worse as the months dragged on. After going through a sleep study, my doctor reviewed the results, told me about my AHI and various other fascinating acronyms, and finally prescribed a CPAP machine -- a device that blows air up my nose, effectively stenting open my airway with air pressure. The idea is to prevent the airway from closing, and thus get that AHI number down -- so the patient has uninterrupted sleep.

Getting the CPAP machine was an adventure. My prescription was sent to a medical device sales company in my area. That company called me one night and set up an appointment for me to come over (they're "down by the airport") and get fitted for my new sleep gear. My appointment was set for 5pm on a Thursday, and I'd be part of a "class" of people all getting their machines at the same time.

REMstar Auto M SeriesI was the youngest person in my class by about twenty-five years (I'm 30; the oldest person there was pushing 80). Everyone was given a CPAP machine, though they differed quite a bit based on prescription. Mine was a REMstar® Auto M Series, with a heated humidifier attachment. (Pretty sweet, huh?) Without going into all the specifics, the CPAP machine is programmed with various information from my prescription (specific air pressure ranges), and it does some amazing things -- for example, it is able to detect apnea/hypopnea events and records them internally. It also records the specific air pressure used at all times, and builds an internal log of the entire therapy process. This information goes on a smart card which is later sent back to the medical services company, who work with doctors to analyze it, graph it on a computer, and make sure everything's copacetic. In addition to the machine itself, I was given (okay, sold) a six-foot length of air tubing (about 1" in diameter) and a mask that attached to my nose to actually deliver the air into my respiratory system.

ResMed Swift LTThe mask is a whole story of its own. While the CPAP machine's usage is pretty straightforward for the patient -- you press one button and it starts blowing -- there's all kinds of stuff you can do with different mask styles. Masks need to be fitted, adjusted, and regularly cleaned, and there are many opinions about which masks are best for various situations (though the global advice is just to get something that "works for you"). My doctor had recommended a "nasal pillow" mask for me based on my dislike of the over-the-nose cup used in my sleep study. I didn't like the cup because the straps to keep it on were super tight, the cup irritated the bridge of my nose, and it leaked a lot of air, blowing continuous blasts of air into my eyes all night. In contrast, the nasal pillows are sort of like little nose plugs -- they stick directly into your nostrils, and deliver air through a big hole in the middle of the "pillows." The amount of headgear touching skin with this mask is far less than with a cup style mask, and I liked that idea. I ended up with a ResMed™ Swift LT mask (better pictures here). It's much less invasive than the nose cup, but my doctor had warned me that nasal pillows freaked some people out -- the issue being that using this mask involves closing your mouth, sticking something very like nose plugs up your nose, and then trying to go to sleep. Your brain isn't used to this situation (mouth and nose both covered), and rebels, thinking that you're being suffocated despite the tons of air pumping through the system. Also, the nasal pillows concentrate the air flow into nostril-sized holes, so the pressure feels higher than when using a nose cup or other large-area mask. It took a conscious effort for me to relax past the suffocation panic and let the system work, but I liked the idea of the nasal pillows since I'm a side-sleeper, and I felt that less headgear was better.

So I had the gear: CPAP machine, air hose, and mask. The class instructor told us various stuff about how to use it, particularly recommending the "ramp" feature on the machine, which starts off blowing air at a low pressure, then ramps up to full pressure over the course of a half hour. My machine happens to have a "flex" function which automatically decreases the air pressure when I exhale, which increases comfort. The instructor also recommended that we disassemble everything -- mask, hoses, humidifier attchment, air filter -- and clean it every day. This isn't a ton of work, but it's far more infrastructure than most people are used to just to go to sleep and wake up in the morning. But I dutifully listened, and even bought a gallon of distilled water for the humidifier on my trip home. (You have to use the distilled stuff, or minerals build up in the machine. Given the expense of the machine, I listened.)

I set up all the equipment, put on the mask, and started the flow. Within thirty seconds I ripped off the mask and was gasping for breath. My brain was screaming -- suffocation! -- and somehow it seemed much worse at home lying in bed than in the class. I chilled out for a while and tried again, but still the sensation was too intense. I switched to the nose cup mask I had disliked in my sleep study (they gave it to me to hang onto), and that was a lot easier to handle. So on my first night, I slept with the nose cup (plus an Ambien) and it was...tolerable. Except for the rain-out.

Rain-out is a phenomenon where water condenses inside the mask and air tubing, because the air in there is warmer and moister than the air in the room. This was certainly true in my room, which was probably at 60 degrees F, and I was using a heated humidifier on the CPAP machine. The result was water condensing in the mask and literally raining on my nose (and sometimes up my nose). No fun. There are many potential solutions to this problem, but so far what I've done is simply warm up the room and reduce the heat on the humidifier -- there's still a little condensation, but not enough to bother me. Aside from the rain-out, the other problem is just getting used to having something strapped to your head all night. This is genuinely weird, and takes some getting used to. A final issue is the restricted range of motion you have when you're attached to a mask and air hose -- rolling over in bed requires a little planning, and I had to reconfigure my pillow setup. (But frankly, as a geek, this was kind of fun.)

In subsequent nights, I switched back to the nasal pillow mask. Although it was hard to get past the suffocation reflex, I just kinda powered through it. Now that problem is mostly gone, and I'm able to get past the freakout sensation with a minute or two of calm breathing. I like the nasal pillow mask far better than the nose cup -- it's more comfortable, it's smaller, and overall it just feels like a better fit. So I'm happy. I must say that getting used to CPAP is genuinely challenging -- I can see why some people give up. There's a lot of gear and maintenance involved, and you have to change your sleep routine permanently. But in my case, the daytime sleepiness had just gotten too bad -- there was no way I was not going to use CPAP. I needed a change, and CPAP was going to give it to me, if I put in the work.

So what's my progress? In my first two weeks on CPAP, my AHI has gone from 48 to 0.7. So I'm still having the occasional sleep-interrupting event, but vastly fewer than before. I'm also routinely sleeping through the night, whereas before I would wake up repeatedly (up to ten times a night), and often got up to visit the bathroom. This is just gone -- my body no longer seems to feel the need to dump liquids at night. I no longer wake up thirsty; there's no real need anymore for a glass of water by the bed, which is a big change. My blood pressure has gone down. I'm losing weight. I'm also dreaming much more, and the dreams are intense and memorable. I'm still sleeping 10+ hours a night, which seems like a lot, but maybe I'm paying down a sleep debt? I'll have to ask my sleep doctor. The best part is I'm more wakeful during the day. The wakefulness isn't perfect -- there's no miracle here -- but it's clearly a lot better than before, and the fog is clearing. I'll see my doctor next week, and we'll review the machine setup and the data, to see how things are going.

So my overall experience with my sleep apnea diagnosis has been positive. It's frankly a lot of work to go to a sleep doctor, fill out forms, go get a sleep study, figure out how to sleep during it, go back for more review and testing, get the machine and mask, set it all up, maintain it, and use it -- but the upside is enormous. And the potential downside (leaving it untreated and never being properly rested) is horrible. So I'm sticking with it. For those who haven't yet been diagnosed, I encourage you to be persistent -- you have to be your own advocate within the medical system. But there are many people who have gone before, and have shared their experiences online.

Please share your experiences in the comments. I've already heard from many readers with sleep apnea, and I've been very encouraged by your stories! Thank you. Also, I found the forums at cpaptalk.com encouraging and enlightening -- many of those folks have Gone Pro with their sleep apnea, buying special software and hardware to monitor their CPAP data. It's inspiring -- and this CPAP machine gives me a new thing to geek out on! The community over there has answers for pretty much any question, and it's a great resource.

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October 17, 2008 - 10:42am
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