+- Apnea Board Forum - CPAP | Sleep Apnea (https://www.apneaboard.com/forums)
+-- Forum: Public Area (https://www.apneaboard.com/forums/Forum-Public-Area)
+--- Forum: Main Apnea Board Forum (https://www.apneaboard.com/forums/Forum-Main-Apnea-Board-Forum)
+--- Thread: Currents thought about titration study (/Thread-Currents-thought-about-titration-study)
Currents thought about titration study - BrassCat - 06-08-2017
Hello the Forum,
No knowing any better, I used to think the overnight study was a gold standard for testing and knowing the condition of someone's sleep apnea condition. I myself have had four overnight sleep studies. the first was around the year 2000. In retrospect I know I had sleep apnea very bad. When I woke up at night it was like my room was lit up in a psychedelic manner. When I got up in the middle of the night to make a bathroom visit, putting my foot down on the carpet produced circles of light emanated from my foot and going across the carpet like ripples I would see if I put my foot into a pond water. My fatigue was tremendous. Sleeping 12+ hours a day, sleeping most weekends so I would have the energy to work come Monday. The CPAP machine I received did no good. I did not have the energy to do follows. Best of my recollection, it had a decal marked 5 cm. My machine was a Silent Knight. I was using a nasal mask. I was afraid of suffocating if the machine lost power with a full face mask. That 1st overnight study was done in the hospital room at the University of California in Irvine.
For many years my primary care Dr. would not repeat an overnight study nor running an overnight oximeter test . He said I was already tested. I became disabled no longer work able to mentally function in computer programming and engineering. I was retested in 2010, finally. That overnight study determined that I needed a CPAP pressure of 10 cm. I got a new Phillips Resperonics CPAP. It was also determined during at that sleep study that I was beathing thru my mouth. So perhaps for up to 10 years I was using a nasal mask to little effect.
To verify the functioning of this new machine and settings, I ran an overnight oximeter test. It showed my blood oxygen using the new CPAP machine and pressure settings. I was still desaturating significantly. It did not seem that this sleep lab offered any further monitoring or assistance. A representative of the pulmonary supply company stated I should get an auto CPAP machine. Using this Philips auto CPAP, my blood desaturation came under control. My pressures went anywhere from 13 up to 16 cm H2O. I really had to strap that full face mask down to keep from the mask leaking. Nobody knows how effective that really was from only monitoring my blood oxygen for two nights. I figured it was working because the pressures would climb during the night. This was now on my third CPAP machine. At this point, I had no idea I could still be having with lack of REM sleep. I had very little REM sleep at the lab.
I did another overnight somewhere around 2004, because I was in a stupor. Did not care for that lab, the attendant was unfriendly, through the night therefore I felt uncomfortable. The sleep study showed that I was getting very small amount of REM. They were able to established pressures, but those were low compared to the Auto CPAP. At the time of the study I have been taking prescription temazepam, now up to 30mg a night. That is not good medication (I believe it is being phased out of used). I had developed an addiction (doctor prescribed). The pulmonologist said I should stop taking temazepam because it interfered with my sleep (Rem). I found it took one year of tapering down to stop taking temazepam, due to nasty side effects.
My last sleep study was December 2016. From that study I was prescribed a Dream Station Auto BiPAP. I was not feeling so good using this machine, and requested a prescription for an oximeter, doctor would not do that. I needed to use the clinics oximeter. Which lead to an overnight oximeter test. The test showed I was going down to 79% blood level oxygen with this new titrated Auto Bi-Pap. He then stated that (trying to remember how this was stated) they would not be able to control my apnea (from desaturating). That I needed to start using my oxygen concentrator again. This test result and his comments lead to this apnea forum, which lead me to Sleepy Head. Hello
.-----------------------------------------------------------------------------
so I digress. This was just history leading up to today .-----------------------------------------------------------------------------
In speaking with people that I know that I also found they too suffer from sleep apnea, they seem to report to me that their sleep lab's come in with titrated pressures lower than what they really need at home. As hard as perhaps some sleep lab's try, it is not your own bedroom and it is not your own bed you are sleeping in. You are in a strange place. Some labs really try to make you comfortable. Two of the sleep lab's I've been in were decorated nicely. Attendance / therapists were friendly. Still... you do not sleep the same.
I know from the comments made by the overnight respiratory therapist at my last sleep lab, she worked very hard to get an exact titration. My therapist commented to me, she was having a difficult time getting my lungs to release. Meaning I could breathe in but then I wasn't letting the air out (exhale). I guess that's how, in part, I got to a BiPAP machine.
At this point in time, after joining this board, reading posts, also studying sleep apnea articles on the internet, and the fact that I now know that I am experiencing hypopneas, obstructive apneas, periodic breathing, and central apneas, that I have come to understand this is a complex apnea condition. Besides that, Sleepy Head shows me that my sleep is not at all consistent from night to night. It can be much worse, it can be so-so. That being the case, how can a sleep lab determine an accurate titration and understand my true apnea condition except for the night of the study only. My true sleep apnea condition is best understood from the whole set of overnight records, as recorded by my Dream Station (or other pap machine that records these conditions nightly) , as presented with software such as Sleepy Head. The Pulmonologist has his own software but comes at a greater expense. The equipment you can get is determined by the sleep lab study (insurance). All from that night.
In researching Sleepy Heads file formats, I found that the actual apnea events are actually detected / determined in the smart Pap machine itself. Sleepy Head is a sophisticated and wonderful computer program, a kind of GUI. For those not into computer software, a GUI is in an acronym for Graphical User Interface. It is a wonderful way to display recorded data. Sleepy Head does not determine whether/when you've had and apnea, hypopnea, periodic breathing, or clear airway. It is constructing the waveform graphs from different streams of data in files while adding in the proper positions in these graphs the events listed by the Dream Station software. It's wonderful. It tells me so much about how I'm sleeping.
Perhaps I have not been focused so close to titration studies as I thought I would. But my best feeling right now are comparable to an Indian parable of the blind men and the elephant. I remember the impact of the parable but don't remember the exact words. One man who grabbed the elephant's trunk said the elephant was like a snake. Another thought it was like a tree trunk because he grabbed around it's leg. Another said it was like a leaf because he handled the elephant ear.
I guess my feeling is if one has complex apnea and that condition is quite variable from one night to the next, then the sleep lab's report only represents one point in time and does not truly represent one's true sleep apnea condition.
Thanks for enduring my ramblings.
RE: Currents thought about titration study - PaulaO2 - 06-08-2017
And this is why we look at trends, not one or two night's worth of data. No two nights are the same (that's gonna be on my tombstone I think). Too many variables go into sleeping. So we encourage everyone to gather data via SleepyHead for at least a week, hopefully more. This allows you to see what is your "normal". And a "normal" won't be "My AHI is 3". It will be "My AHI is between 2.6 and 4". Once you understand your normals, you can look at the data and immediately see if something is changing.
Bilevels can take some getting used to. There are a lot of settings to them, not just a minimum and maximum. If you need further help with the settings, just ask. SleepyHead screenshots are helpful, too.