Monday, April 04, 2005

My (Former) Sleep Habits

I don't know if this would be of interest to anyone, but I found it fascinating.

Here is the actual chart of the first night of my sleep study. I was wired to detect everything detectable about me, but with no breathing assistance:

(click to enlarge)

You can see I went to sleep at 10:21pm and was awoken at 7:05am for about 8-1/2 hours of sleep. Even with my cold, it was the best night's sleep I'd had in several days :)

The top line shows sleep stages, with accompanying periods of dreams in the darkened in areas. You can see I had some shorter dream periods about an hour into sleep and another a little after midnight. Then what's really interesting to me are the two dream cycles at about 3:45-4:05am and from about 6:15-6:50am. I remember these two dreams having occured (the first was fairly intense, while the second very detailed). I remember wondering if they had recorded these instances and, indeed, they had.

The second line is sleep position, of which I slept on my back most of the night except for between 4:30-6:30 when I slept on my side. Sleeping on my back, as you'll see later, is what causes a lot of my sleep apnea problems.

The third line records each instance of breathing anomolies during my sleep, which is where things start getting interesting. Hypopnea is a slowing down of breathing in general, while apnea is the brief stoppage of breathing altogether. From the tons of little lines on the hypopnea row, you'll see I slowed my breathing down to abnormal levels hundreds of times during the night, and the apnea line below shows I actually stopped breathing (for only a few seconds at a time) during the deepest parts of sleep. Correspond that to the first major dream cycle (which was the intense one) and you can see that it actually was very high. The doc said I recorded over 350 episodes of apnea/hypopnea during the night, which averaged out to around 45/hour. That's basically a little more than once a minute I stopped breathing for a short period. A good range is about 5-15 episodes/hour, of more concern is about 15-25 episodes/hour. You can see now where I actually stand. This, my friends is what is technically referred to as Not Good.

And here's the kicker.

The fourth line shows oxygen saturation, which most of you know is kind of required for healthy living. Normal human beings live their lives, then slumber blissfully with an oxygen saturation level of about 90-95% in the bloodstream. For me however, even in the first half-hour to hour of sleep the readings fluxuated up and down as low as 80%. Then, corresponding to those deeper levels of sleep, beginnings of dreams, and increased episodes of apnea/hypopnea the O-2 saturation went down to 70%, then in the middle of the night actually got down to a low of about 65% for a brief time. That information, combined with the other readings is what compelled them to bring me back for a second round of study the following week.

More on the follow-up visit and the readings that resulted next time.

No comments:

Post a Comment