Thursday, November 15, 2007

Ok... so that was weird.

So I spent the night in a sleep lab.

I'm a notorious snorer around these parts, so last time I was at the doctor I mentioned this and my doc referred me to the sleep lab. Michelle has always said that she thinks that I have sleep apnea, so I thought this would be a good time to find out.

The procedure started a few weeks ago. I was sent to a place called Sleeptech where I was given a portable blood-oxygen monitor. This device clips on your finger and tracks your blood-oxygen levels over time while you sleep. I took this home and slept that night with the monitor doing its thing. The next day, I returned the device and awaited the results. During the followup, the doc at the actual Sleep Lab at Surrey Memorial Hospital said that it looked like I did have sleep apnea; however a full overnight oximetry test (or polysomnogram) would be required to fully diagnose. This sounded interesting, so I signed up and waited for my appointment.

Yesterday, my date finally arrived. I arrived at Surrey Memorial at about 10:00pm and found my way to the sleep lab. The tech told me to get into my sleeping wear (shorts and a t-shirt... no underwear and you must wear a shirt). Then she proceeded to wire me up, and wire me up she did....

I had roughly the following:

    Multiple sensors connected to my scalp
    I think there was one or two on my forehead...
    2 sensors - one behind each ear
    2 nose air flow sensors of some kind that fit into my nostrils
    At least one chin sensor to watch for teeth grinding
    2 sensors - one on each of my legs below the knee (for leg movements measurement)
    2 sensors on my cheeks
    1 sensor on my finger to measure oxygen saturation
    1 strap around my chest to measure chest wall movement
    1 strap around my belly to measure abdominal wall movement.

It was actually a bit of a funny process. While I was being wired up there were multiple other computers monitoring the 4 or 5 other patience that had already arrived and were already in different levels of sleep. The rooms are all private - just a tiny room with a hospital bed in it + a table. There are 'night-vision' cams in all the rooms, microphones to hear the person and speakers so the tech can talk to the patient from the monitoring station. One of the other patient's had already started snoring... another was complaining that she couldn't sleep.

30 minutes later, we were complete and wired. I was then instructed to go lie down in my bed and I was 'plugged' in. From there we had to test all of the sensors and connections. There was a lot of "Ok... now move your legs, good, now grind your teeth... excellent, now snore" Finally we were ready, I asked for a glass of water and decided to read for a bit to make myself drowsy.

20 minutes later I decided it was time to attempt to sleep and requested the light to be shut off. (With 20 or so wires and tubes coming off my body, it wasn't as if I was mobile enough to get up and shut it off myself ;-) )

I closed my eyes and immediately fell fast asleep....NOT. Do you know what it's like trying to sleep with tubes, wires and sensors taped to your body all over the place? Meantime I could still hear the nurses outside my door talking, the guy in the room beside me snoring, and the person 2 doors down requesting help to go to the washroom. It seemed like an eternity to fall asleep. Finally when I did fall asleep, I think at one point the nurses accidentally turned on my speaker to respond to another patient.... it took a while for me to recover from that too.

Anyway, long story short, I had a terrible sleep. In the morning the nurse came in and removed all the sensors and that was it. I'll follow up when I get the results, although the nurse already said that it appeared that I had sleep apnea and woke a lot. Well no kidding.


  1. Did you ever get any info back about this?

  2. Yes.

    So, a few weeks after my overnight test, I was called in for a consult with the doc. He gave me the results - AHI 20, RDI 60.

    The best explanation I have found online for these references is at

    First some definitions:

    Apneas: Reduction in airflow of >= 90% of baseline lasting for at least 10 seconds.

    Hypopneas: Reduction in airflow of >= 50% of baseline with a 3% of desaturation OR a reduction in airflow of >=30% with a 4% desaturation AND lasting for at least 10 seconds

    AHI: The Apnea/Hypopnea Index. Apneas+Hypopneas/hours of sleep. 5-15 mild, 15-30 moderate, 30+ severe.

    RDI: Respiratory Distrubance Index: Apneas + Hypopneas + Respiratory Effort-Related Arousals/hours of sleep. (RERA's are events that don't quite meet the definition of apneas or hypopneas, but are increases in repiratory effort leading to an arousal from sleep). 15-20 mild, 20-40 Moderate, 40+ Severe.

    So, bottom line, I had a moderate AHI and severe RDI. I was basically being aroused from my sleep by respiratory events approx 60 times per hour... once per minute.

    He prescribed CPAP treatment - Continuous Positive Airway Pressure. ( has a good description although the pics are a bit out of date. The newer machines have a much less obtrusive headset)

    So, yes, I need to wear ridiculous headgear every night. However, the headset is not too bad - just a couple of straps with fairly small nose pillows that push up against your nostrils. The machine took some getting used to, as it pumps air into your lungs to keep your airway open. Having said that, these are intelligent machines that adjust the pressure as required, decrease the pressure when exhaling, have humidifiers to not dry out your airways and are very quiet. The biggest discomfort is the hose - but I've found methods to limit the amount I 'get wrapped up'. All in all, I've slept with it nightly for the past couple of years and I'm very used to it. My biggest hurdle was getting over my vanity and pride...

    This treatment has completely resolved my sleep apnea and I am _much_ better off. When I wake in the mornings, I actually feel like I slept - which was quite unusual when first experiencing it. Over time, it has helped improve my overall mental state enormously.

    For those of us BCIT CST grads, if you recall those months of no sleep - that is very much how I normally felt (although BCIT made it _far_ worse ;-)). Now, life is good and still getting better ;-)