How to read report

Ok I posted a few weeks ago about having trouble doing the second study because I could not get past the mask. I am going back to actually see the doctor in early Jan. In preparation for the visit I obtained a copy of the original sleep study. I am looking for help in interpreting it. Before anyone says "See your doctor," yes of course but it would help if I had some idea of what to ask, etc. So here goes the data and my questions thus far, in italics/bold)

Latencies:
Sleep Onset: 60.2
N1: 60.2
N2: 76.7
N3: 93.7
REM: 184.7

However, later in the report, under durations, it states: ( I am guessing the above is how long it took to reach each state and the below is how long in each stage. If so the numbers above are not correct, as I remember watching at least three TV shows before even trying to sleep?)

Time in Bed: 430
Sleep Period Time: 362.5
Total Sleep Time: 273.5 (So I was in bed for 7 hours and slept ~5?) But if I add the times above I get ~7 hours. So are not N1 , N2, N3, N4 all sleep stages?)
SWS Time 35.5 (What is SWS?)
REM Time 42.5
NREM Time 231 (Non REM?)
Sleep Efficiency 63.6% (Good, Bad, does not matter?)
WASO: 93.3 (WASO ???)
TWK Time 156.5 (TWK??)
Inter-Sleep WK 24.6% (???)
Stage Shifts 51

Then the report does a break down of types of sleep WK(SPT), WK (TIB) [both are waking? but what is SPT and TIB], REM, N1, N2, N3

The next section is Respiratory Data --Just the top line, Number of events, for now. I can provide further info if needed.-

CA-3, OA-1, MA-0, Apnea-4, Unclass. Hypop-33, Central Hypop-1, Obs. Hypop-0, Hypop-34, A+H-38, RERA-2, Total-40 (OK what are these, one note at the bottom is that hypopneas scored based on 3% desaturation, so I am guessing the hypop. are counts of times my O2 level went down, and the unclassified are the times it went down but not by 3%?) Also, provided is a score of Central AHI: 0.88/hr. (good, bad, ??)

Related to the O2 levels a few items: Average SPO2 (TST) 94.50, Average SpO2(TIB) 95%, # Desaturation 18 (why does this number not match the hypop # above?) Min Sp02 Value During TIB 91%, Min SpO2 value during TST 90%. (As I understand it the issue with sleep apnea is that you are not breathing resulting in your body not getting O2. This reduction of O2 causes your heart to try to pump faster and other issues with reduced O2 supply which eventually wake you up and cause poor sleep. I have also read that your O2 level, even in people without other issues, drops during sleep a few places mention ~87-88%. Of given this, regardless of the # of events, drop of O2 levels, I never seem to go that low. So what is the issue???)

The next section is Oximetry Summary: it is a graph with SpO2 and Stage plotted vs time. SpO2 stays above 90% the entire time.

The next section is Snoring Summary:
Snoring Episodes - 0
Snoring index N/A
Total Time with Snoring 0 min [i](I put this here because later the report talks about snoring???)
[/i]


The report then provides Cardiac Summary:
Average pulse rate (TIB) - 75
Highest pulse rate (TST) - 96
Highest pulse rate (TIB) - 104 (what are TIB, TST, TIB) (this data is not surprising as the entire reason I was there is that I had AFIB and had not yet been cardioverted. Which raises some questions for me regarding the next section..)

Cardiac Event Observations
For each type the report states none including for atrial fibrillation so either the sleep study missed the fact that I was in afib or I was cardioverted the next week for no reason?)

The report goes on to give details technicians notes, another graph, etc.

Next to last section is Diagnosis First: Obstructive Sleep Apnea, Second: Snore ( earlier it clearly states no snoring events)

The last section is Impressions: (Seriously impressions, did they stare into a crystal ball or what?)
1. Obstructive Sleep Apnea, Snoring, Hypertension
2. Patient had an overall AHI of 8.3/hour (I am not sure what this means. but my guess it is the total # of apnea + hypop. divided by the number of hours of sleep?)
3. Patient's sleep was moderately fragmented. (really I wonder if this had any thing to do with the pain down my right hand due to the pulse ox sensor? I remember waking several times a switching it from one finger to another to try and alleviate the pain being caused by having my finger held straight all night.)
4. Patient's snoring consists of snorts. (???? again this seems contradictory)
5. There was no evidence of periodic limb movements during the procedure. (Could that be because the tech told me to sleep on my back and try not to move? Every time I woke up I tried to stay as still as possible, with the exception of moving the pulse ox sensor?)

Any help in interpreting this report or figuring out what to ask the doctor when I see him would be appreciated. I am particularly interested in any comments regarding the following three items:

1. Snoring study seems to say both yes and no???? (My wife says yes, and some times I would agree)
2. The issue with having afib but the study reporting no afib?
3. The AHI score. Given that most events, 33 events out of the total 38 events, were unclassified is this score even meaningful. If most of the events were hypop. of less than 3% desaturation and I never went below 90% saturation, which seems typical of healthy sleep, what is the issue? Or does the unclassified label mean something else?

To answer a couple of your questions:

SWS : https://www.google.com/search?q=SWS&ie= ... r+in+sleep

WASO : https://www.verywell.com/understanding- ... so-3015394

all the other question would be better answered by "Google"

https://www.google.com/search?q=hypopne ... 8&oe=utf-8

I seem that you had a fairly good sleep study and have a Diagnosis of "garden verity of OSA",(https://www.google.com/search?q=OSA&ie=utf-8&oe=utf-8), and would probably benefit from a Cpap machine.

Latencies:
Sleep Onset: 60.2
N1: 60.2
N2: 76.7
N3: 93.7
REM: 184.7

Sleep Onset means the time from trying to go to sleep until the first time actually asleep.
The others mean similar things: for the first time in stage N1, etc.

Time in Bed: 430___________Total time in bed for the test
Sleep Period Time: 362.5____Total time from sleep onset to awakening to get up
Total Sleep Time: 273.5_____Total time actually asleep
SWS Time 35.5_____________Total time in slow wave sleep
REM Time 42.5_____________Total time in REM sleep
NREM Time 231_____________Total time in Non-REM sleep
Sleep Efficiency 63.6%_______Total time asleep divided by total time in bed - this number is not very good.
WASO: 93.3________________Total time awake between sleep onset and awakening to get up - Neither is this one.
TWK Time 156.5____________??? Seems to be the sum of the sleep onset and the WASO times
Inter-Sleep WK 24.6%________??? Seems to be a measure of how much time was spent awake during the sleep interval
Stage Shifts 51______________Number of times shifting between stages of sleep

Average pulse rate (TIB) - 75__Average pulse rate for the total time in bed (TIB).
Highest pulse rate (TST) - 96__Highest pulse rate during the total sleep time. (TST)
Highest pulse rate (TIB) - 104__Highest pulse rate during the polysomnogram.

Desats are the number of times that the SpO2 value dropped by 4% or more.

The snoring reference indicates that the events were snorts (short noises) and not real snores. That happens with some apneas/hypopneas when the airway partially closes but immediately responds to a breathing attempt.

The main questions I would ask of the doctor are:
Does an AHI of 38 indicate a severe level of sleep apnea?
Do I need a titration study to determine the pressure (ranges) needed to correct the sleep disordered breathing?
Are the wake times related to apneas so that is the reason that I wake up so frequently at night?

EDIT: BTW just because you are sometimes experiencing AFIB, doesn't mean that it will always appear during a sleep study.
AFIB is one of the complications of untreated sleep apnea and your referring doctor did the right thing to order the sleep study to see it sleep apnea could be a contributing factor.