The results from the sleep test that I took last month are in. The test experience was a contradictory mix of painless medieval torture. After all the electrodes were super-glued to my scalp and legs, two tight belts were placed around my abdomen and upper chest (under armpits between breast and chin), a mask-like device with silicone appendages that go up the nose was strapped to my face, and an oxygen-sensor was clipped to and securely taped to my pointer finger, I was ready to catch some zzzz’s. But here was the problem: I am a belly-sleeper. Always have been. And I quickly discovered that this sleeping position is either (a) not one that occurred to the minds of the test evaluators as being at least a remote possibility at the time they designed the test, or (b) an evil that must be irradiated from the Earth, and my
torturers exam-administrators considered themselves to be the first line-of-defense.
For starters, the massive braid of wires that emerged from the top of my head, connected to a rather chunky electronic box that was laid beside of my pillow, was not conducive to being twisted, as would be the consequence in going from the initial laying-on-my-back to laying-on-my-stomach motion. (At one point, as this long thick bundle of wires was not-so-gently tugging on the top of my head, I must have briefly drifted into dreamland: I spoke Na’vi and swear I had blue hands. Or perhaps I was just performing in a Blue Man concert. Dreams, you know, can be confusing — especially under duress.)
Believe it or not, the worst constraint wasn’t this hair wire braid, but the damn oxygen sensor. This long clip that had been duct-taped to my index finger would have served very effectively as a splint, as it allowed no bending motion whatsoever in that finger. Annoying, yes. But what really caused problems was the sensor’s location: it was taped to my left hand and plugged into the wall-mounted electronics box that was on my left side when I was on my back. However, the act of rolling over onto my belly required considerable thought — it was a problem of topography and knot theory eliciting deep mathematical constructs and serious planning before initiating the motion.
First, the wire to the finger wasn’t quite long enough to permit said finger to be positioned on the side of the bed opposite the wall electronics box, as would be the case if I were on my belly. To successfully transition to a face-down position, I first had to scoot towards the electronics box as much as I could, half-dangling over the edge of the bed, to allow enough slack in the finger sensor to enable my left hand to move under my body and to the other side as I rotated in a face-down position. And of course the hair thing wasn’t going to allow itself to be twisted in a crocodile-like attack without demanding some attention, so I had to reach up, untwist wires, reposition the separate electronics box those wires were attached to. Even after all that effort, my left hand felt like it was on a very short leash — it couldn’t go just anywhere it wanted, like under my head, where it usually likes to hide out for the night (the one time my left had instinctively tried to go under my head, it got in a fine tangled mess with the gazillion head wires … ga!) Every time I needed to make an adjustment in the way I was laying, I had to go through the above exercise. And so went the night …
The next morning, I would have sworn on a stack of bibles that I didn’t get more than 2 hours of sleep, tops (and even those 2 hours were very atypical of a normal night of sleep for me). The report claims otherwise. It claims I fell asleep 23 minutes after lights-out (I must have done all that wire rearranging more quickly that I appreciated. I’m a mathematical genius!), and for nearly 5 hours (when adding up all the fragmented sleep times amongst the wake times).
But the biggest result was: my oxygen saturation remained in the normal range (a dip down to 89% was just a blip, and believed to be an artifact in my case — as I understand it, O2 levels are supposed to remain above 90% in a healthy individual). In other words, I have ruled out one possible explanation for the retinal atrophy in both of my eyes. From that perspective, this seemingly restless night was a successful experiment that provided useful data.
Because one of the core values of my blog is “data sharing”, I present the sleep test results below, in case you’d like to compare to your own sleep test results:
In the above, Oxygen Desaturation Index is extremely low (the lower, the better). In combination with the low AHI value (again, lower is better), a sleeping problem that could be the underlying cause of my eye issues is effectively ruled out.
I’m sure that my sleeping efficiency is close to 100% when at home!
Oxygen saturation should stay above 90% . Apparently there was something like a microsecond in which the sensor registered 89%. Given that this value was during a wake period, and of such short duration, the technicians consider it an artifact.
I was actually concerned about the low pulse rate (45 beats per minute!); perhaps low blood flow, rather than low oxygen content, could deprive my retinas of needed oxygen? I asked about these low values, and the sleep doc assured me that these values were normal.
I didn’t find these strip charts to be very helpful, as they are virtually unreadable. They remind me of plots that I might have made back as an undergraduate, using 1980’s computer technology.