Obstructive Sleep Apnea (what they don't tell you)
- You can have obstructive sleep apnea (OSA)
and not know it. 10% of people do. My wife never notices I stop breathing. I
snore loudly so I went in to be tested for surgery. They had me do a sleep
study. Turns out I have 33 "events" (hypopneas plus apneas which
is called Respiratory Disturbance Index (RDI) or equivalently, Apnea
Hypopnea Index (AHI)) so I am not sleeping as fully as as should be since my
body awakes every 2 minutes to fix the relaxation of my tongue, basically.
My oxygen saturation drops to 87% which isn't really bad, but it isn't great
either.
- Apnea=stop breathing for 10 seconds or more.
- Respiratory Disturbance Index (RDI) is the sum of
apneas, hypopneas, and upper airway resistance (UAR) events. AHI = Apneas +
Hypopneas. Hypopnea is a reduction in the flow channel of > 50%
with a 4% drop in oxygen saturation.
- The diagnosis of OSA does not require an AHI of
33. A patient with an overall AHI of 10 may be clinically significant, many
patients suffer from REM related OSA and can have severe oxyhemaglobin
desaturations during periods of REM sleep.
- Apnea and Hypopneas both disturb your sleep equally well which is why they are often
combined as if they were the same type of event. If you have >30 apneas
per night, you have "sleep apnea." In my case, I had 78 apneas
(and 98 hypopneas), so I qualify.
- The likely cause: your tongue muscles relax, blocking the airway. The soft palate
can contribute to the noise in snoring as you suck air.
- Several solutions:
- Surgery: pull tongue forward in front (increase tension on tongue),
remove tissue from soft palate. Problem is even if they scope you with
fiber optics, they can't guarantee surgery will reduce the problem. And
the recovery is 3 weeks on soft foods...A tracheostomy is guaranteed to
fix the problem, but you wouldn't want to have it done.
- Dental device: pulls lower jaw forward but still allows side to side
movement. might be a good first try before surgery (use an oximeter to see
if it makes a difference; see below)..
- CPAP or auto PAP machine: the auto PAP operates at a third lower average
pressure so it is slightly more comfy. I'm getting the GoodKnight 418P
with the software, and the Breeze mask which is the most comfy around. You
must breathe only through your nose, but even for mouth breathers, this is
pretty natural.
- Newer experimental surgery: removes stuff at base of tongue. Most people
don't know about this...still experimental.
- You can sleep with your face straight down (like on a massage table),
which isn't very practical. Sleeping on your back (supine) is the worst
for sleep apnea for most people.
- Your sleep apnea may be positional...e.g., you are fine if you sleep on
your stomach, but not fine on your back.
- be sure to wash out the equipment frequently as recommended by the
manufacturer.
- you don't have to go in for a sleep study to set the pressure if you get
the software for your unit and it measures events, like the 418P. Based on
your body type and the # of events per hour, they can really tell you
pretty close to the pressure you need. For my case, they thought between
7cm to 12cm, i.e., my single optimum pressure is somewhere in that range.
So you start with that and look at the data, and then increase the min
pressure until you only have 3 or fewer events per hour. It's that simple.
ResMed you should adjust the pressure for the proper
curve, but the devices you have at home don't record the curves with
that much resolution. Other people say "you have to look at O2
saturation and the quality of sleep, e.g., how much time in REM, etc. A
1cm pressure difference can make a HUGE difference in the quality of
sleep" I'm not sure I buy that at all. The same person said he like
the AutoSet T which is an auto-PAP machine and you can only control
minimum and maximum pressures, the pressures throughout the night are set
by the machine. Of course, you could really narrow that min/max range to
1cm if it really is that sensitive. I suspect there is a lot of randomness
in the data. At 5 min/8 max, my RDI was 3.7. At 6/8 it was 2.1.
- the 418P costs around $1500 and the software is around $900. If you get
the software you can see if the machine is really doing what is supposed
to yourself.
- the units are really quiet but there is a big difference in noise so see
the unit before you buy
- i found the full face mask (Mirage) to be very uncomfortable (heavy) and
also didn't seem like the quality of the air was that great (sort of felt
like I was breathing in my own exhalation even though that is not true). Takes 2 weeks to get used to.
unplugging the two ports seems to give "fresher
air" (presumably since CO2 is expelled faster) but those ports are
used to input O2, not for output and unblocking them just makes the cpap
work harder.
- the first night I tried this was not restful. it is easy for the mask to
leak if you move. and you must lie on your back with the Mirage.
- if you set it to be in auto PAP mode with wide limits it doesn't work
very well. It thought I should have at most 6.2cm but that is below the
minimum pressure you'd want. And besides, I had 12 events per hour on that
total auto setting. So I need to bring up the minimum pressure to be
higher.
- There is a new Mirage
Ultra out now. My recommendation is try the Breeze first, then the
Mirage ultra, and last try the full face mask if all else fails.
- The newest Breeze mask has a (completely noiseless) round blowhole
instead of the (super noisy) square one on the original Breeze. Breeze has
hardly any leakage and is very comfortable.
- The CPAP machine can take several weeks to get used to so don't expect a
miracle on the first night; it will likely be worse sleep for a couple of
weeks until your body adjusts (some people can't tolerate it).
Some experts believe you needn't go to a sleep lab. Here's an excerpt from the article below:
Even after a through evaluation by the dentist and the
physician a definitive diagnosis of OSA can only be accomplished by a sleep
test called a polysomnogram. During sleep, a polysomnogram measures
ventilation, gas exchange, cardiac rhythm, the number and length of apneic
episodes, assesses oxygen saturation, determines sleep stages, and detects
arousals. In the past , this test could only be done in a hospital sleep
clinic. Today, we have mobile sleep technology that allows you to take this
test in the comfort of your own home.
Side effects of untreated OSA: MI, CVA, and insulin resistant diabetes
Questions to ask:
- If you recommend UPPP, why not LAUP? Answer: LAUP does
nothing for sleep apnea, only snoring.
- Why not try a dental appliance before surgery since although
several surgical procedures are used to increase the size of the airway,
none of them is completely successful or without risks. More than one
procedure may need to be tried before the patient realizes any benefits.
Answer: for dental and CPAP, compliance is typically poor and you have to
go through a LIFETIME of inconvenience instead of a short number of days
of pain.
I purchased a device that monitors O2 levels and pulse...a
pulse oximeter. It allows me to review the measurements for the past 12 hours
so it's fine for monitoring my sleep. That seems like it would be a quick
screening device to see if you have OSA since if your O2 levels fall below 90%
during the night, you should go in and be tested (or change your sleeping
position).
Great
article on sleep apnea and treatment options including a full list of dental
appliances such as TRDs, etc.
Another article on
sleep apnea
Reviews of
effectiveness of various dental appliances
Another review
of effectiveness of dental appliances like the Clark AMP, Silencer, etc.
including how to tell if a dental device may work at all for you
The original paper that
tells how to determine whether a dental device will work
Details
on how these dental devices work (and mention of Silencer) including MRI
images
More info on
Silencer
A dental
device from Johns Dental
Silencer FAQ
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