How does this CPAP contraption work?

From the beginning, I've been pretty well kept in the dark about my CPAP therapy. I think my sleep apnea is "mild". My original complaint was insomnia. I was more or less told (over 8 months ago), "put this contraption on your face & everything will be all better". When my CPAP machine was delivered & I asked about controls &/or settings, she brushed me off with, "you don't need to know about those". She asked what type mask I wanted & I said full face, only because my brother recommended. No options were given I can't believe that, in my nativity, I accepted all that.

For 6 months I continually fought various problems, w/o any real solutions/suggestions from my doctor. Then I went on a 3 week trip & for many legitimate reasons, could/did not take my CPAP. Upon my return, suddenly everything seemed to fall into place. I have no idea why. I was sleeping better, awakening more rested, etc.

I "follow my numbers" on MySleepMapper.com. I noticed that about a month after the trip, my AHI, total central apneas, total obstructive apneas and total hypopneas seemed to be "all over the ballpark", while my mask fit was almost always 100%. Reasoning that fewer apneas (not good mask fit) was the objective, I made an appointment to discuss it with my doctor. Her short (ie, irritated) answer was, "OK, I'll have them increase your pressure from 8 to 11". It seems strange to me that she can't change it herself. In fact, I should be able to change it myself, altho' I would need a better understanding of the mechanics before doing so.

How does my REMstar System One 560 series Auto Aflex with humidifier work? It has never been explained to me (even online), except that CPAPs "provide pressure to keep airways open". (What, briefly, are the mechanics . . . fuel is injected into the cylinder; the sparkplug fires, etc) My CPAP starts at 4 and ramps 20 minutes to ?? It has been my understand that ramp started at 50% & went to max in 20 minutes. Does the pressure automatically fluctuate "as needed"? C-flex is on. Pressure usually is much less when I wake up during the night or in the morning than when first turned on at night. What is the 11 pressure? Is that the max?

My "apnea numbers" have dropped since increasing the pressure. But mask fit has gone from 99% 14-day average immediately before the increase to 77% in the following 14-day period. That would be fine with me (after all, lessening apneas is the goal, right?), but the comfort level has gone to hell. My dry mouth is actually painful sometimes when I wake up. I have a chin strap on order & I've worn a cervical collar for a couple of nights & that helps somewhat.

On top of all that, after my DME could not even find me in their system (so that I could order the chin strap), I was so irritated (that's a byproduct of sleep apnea, isn't it?) that I sent an irate e-mail to my doctor. That was 2 days ago & I haven't heard from her.

I've located a nearby A.W.A.K.E. group that I plan to contact. Maybe some face-to-face-real-live-people interaction will ease some of my frustration.

Seems to me that if you pay that doctor or your insurance does and you have to pay for the insurance, you have hired the wrong person. You have already figured out that masks don't seal as well at higher pressures. Insist that whoever provides your mask does a proper fitting and that the doctor you choose backs you up or find a more professional care provider.

The internet is a fine source of info on sleep apnea so self-educate. Keep in mind that all advice isn't equal and some folks giving advice (like me) are not pros and if they tell you to do something or try something as a non-pro, they may be off base as I have found when looking at other forums. Some of the advice I have received elsewhere has been downright stupid and dangerous. The folks here are more careful and professional and responses will be more likely to help but it is your health so self-educate!

Hi @Yabadabadoo. Here is a little explanation of the basic mechanics of CPAP, aside from the fact that the purpose is to help hold the airway open and prevent sleep apnea. A CPAP machine is basically an adjustable blower motor housed inside the unit that is calibrated so that it can be adjusted to various levels of pressure. The machine pulls in room air (much like a fan) and passes it through the blower motor. If a humidifier is part of the machine, the cool room air is then passed out of the blower motor, through the humidifier and over the water so that humidification is added to the air, and then passed out of the humidifier and through the CPAP tubing and the mask. The humidification helps prevent cold, dry air from entering the mouth and nose. The humidifier setting is usually preset, but it can be adjusted by the patient.

Regarding the CPAP prescription, CPAP pressure is measured in centimeters of water. If your pressure is 11, then your prescription was for CPAP at 11 cm of water. The pressure does not fluctuate unless other features, like C-Flex or those that are specific to various manufacturers, are active. If you are on CPAP at a fixed pressure and have a ramp feature, the ramp settings are usually also part of the prescription. The most common I have seen is a ramp setting of 20 minutes starting at usually 4 or 5 cm of water. When the machine is turned on, the machine starts at whatever ramp pressure was prescribed and builds to the final pressure, 11 cm in your case, over the 20 minute period. The starting ramp pressure and the ramp time period are usually adjustable by the equipment provider and are part of the prescription. Some machines allow minor adjustments of ramp pressure and time by the patient. You mentioned that your physician had your pressure increased from 8 cm to 11 cm, and you did not understand why she could not change the pressure herself. The reason is similar to why a physician cannot just change your medication dose and give you a new medication right in the doctor's office. A prescription is usually required and is sent to the provider of the equipment, and they change the setting and continue to monitor your treatment and provide necessary information to your physician and to your insurance company. Some physicians will adjust pressures in the office if they know how to do so, and they can communicate the changes to the home care company and make prescription updates electronically if they have that access. This is less common. C-Flex and similar manufacturer features can be activated to enhance treatment comfort. C-Flex is a feature that causes the pressure to lower, usually within a range of a couple of centimeters, to make exhalation easier. The machine detects your cycle of inhalation and exhalation and lowers the pressure briefly when you begin to exhale and quickly increases the pressure back to the prescribed level to prevent the obstructions that occur with sleep apnea. For patients who are on APAP or other auto-adjusting types of treatment, their pressures can vary and fluctuate within a wider range of settings. These types of machines detect breathing patterns and adjust pressures within the range of prescribed settings to treat obstructions and other types of respiratory events.

When you have a sleep study and are placed on treatment with CPAP, there is usually a pressure (or range of pressures) that work best and are patient-specific. The machine is adjusted to meet your requirements. The reason that patients are not provided information on how to adjust the machines is because the devices are regulated by the FDA and require a prescription for settings and adjustments from a physician. The machines are usually adjusted by a Respiratory Therapist to match the physician's prescription, much like a pharmacist will fill prescriptions for medications in the proper form (tablet, liquid, etc.) and dosage. There is a lot of debate about whether patients should adjust their own settings. The important thing to remember is that improper treatment (too little pressure or too much pressure) can cause continued breathing problems, so it is important to monitor your treatment and make sure you discuss any issues or changes with your physician.

Regarding mask fit and dry mouth, mask fit is a very important component of CPAP therapy. Poor mask fit that causes leak and discomfort is a primary reason that patients become frustrated with treatment. Proper mask fit usually involves working with your equipment provider to try on various masks, checking the fit and the leak levels, and finding one that is most comfortable for you. It is not uncommon for patients to change mask types or styles early in treatment because of discomfort or fit problems. Pressure changes, such as your increase from 8 cm to 11 cm, can also change how well a mask performs. If leak has increased and you are not able to make adjustments to correct that while maintaining comfort and control your AHI (apnea numbers), I encourage you to work with your equipment provider to either get the mask fitted appropriate or to obtain a mask that works with you newly prescribed pressures. For dry mouth, you may need to consider increasing the setting on your humidifier. This will increase the amount of heat so that the water is more warm and moist. The chin strap you mention may also help.

I hope this information is helpful, and best wishes! Please keep us posted on your progress, and we welcome your questions and feedback.

Thanks, so much for the quick replies.

wiredgeorge, I think I've just about reached the same conclusion as you . . . I may have hired the wrong person. I want to get a replacement before dropping this doctor. Selecting a new doctor isn't a simple task. I initially thought this doctor was "the one", because she took time & it wasn't in & out in 15 minutes. Looking back, much/most of the time was trying to convince me that CPAP was the answer. I resisted for about a year, because all that I had heard were horror stories. Then I learned that my brother used CPAP & was happy as a lark. My supplier was Medicare's low bidder. There's always an "equipment person" in the doctor's office when I visit. I gather that his company which, lost the Medicare bid, is for non-Medicare (more profitable) patients. My initial equipment delivery was by someone from Baltimore (50 miles away). Now supplies are handled by a Santa Fe company. My doctor gave me the phone# of a person at the local sleep lab for equipment questions, but I don't really know enough to know what to ask.

Will wonders never cease . . . I just now (as I was typing this) received a return call from my doctor's office. They were closed when I called a couple of days ago, because of a snow storm. Long story short . . . she has checked (with Baltimore) & my chinstrap has been shipped (from somewhere). Changing from the Santa Fe supplier can/will be discussed with the doctor at my next appointment in 3 weeks. I also learned that there are "a couple" of local walk-in outlets for supplies. That seems like a no-brainer decision.

DanM Thanks for your explanation of how things work. On another online forum, I was ridiculed by some for asking the "wrong" questions. I should stop being ignorant, arrogant, etc & just listen to their "experts". Actually, that's why I mentioned my specific CPAP equipment. They told me they can't "adequately" answer my questions w/o that info. Obviously, that's true for some specific questions, but not for very general questions.

My humidifier is set to 5 (max). Dr's office said on today's phone call that maybe I'll be changed to a heated tube; based upon how the chinstrap works out.

C-flex+ = 2 in setup . . . I can change it (to 1 or 3). At least, it changes when I turn the know. I don't know if it would stay changed. I left it at 2.

I noticed this morning when I awoke, several hours early, that the pressure was very, very low . . . much lower than the beginning ramp pressure of 4. I also noticed that I was taking very short, shallow breaths. I've noticed this low pressure a number of times before.

I agree that it's important to monitor my treatment. That's why I get my numbers form DreamMapper/SleepMapper and put them into a spreadsheet so that I can see several weeks on one screen. Altho' in one glaring instance DreamMapper's Mask Fit Time & % "did not compute" with their Leak Time & % for a specific date. Their customer service didn't understand simple arithmetic & finally referred it to their "engineering" department. I'm still waiting for their reply.

My supplier told me in an e-mail, " I cannot continue to send you reports due to confidentiality". I don't understand that at all . . . after all, it's MY data.

On a small side note . . . I thought I saw when I posted this thread, that I was automatically "subscribed" & would get e-mail notifications when replies are posted. I didn't receive a notification. Do I need to set a preference somewhere?

Hello @Yabadabadoo. Finding a local equipment provider will probably be very helpful in your quest for good mask fit and successful treatment, so I hope you are able to find a company that offers good support. Hopefully, the chin strap will help. As for C-Flex, the higher number will provide a higher amount of pressure relief. You can try all 3 settings and leave it at the setting that is most comfortable for you.

As for the very low pressure you describe, this may be an issue that your equipment provider needs to check. I do know of some machines models that will attempt to detect wake or significant sleep disturbance and will lower the pressure for comfort until breathing is regular again, but I do not know if your model has a feature like that. Hope this helps!

I looked over another forum long and hard and saw that folks were being berated for asking some of the same things I needed to know and there was a lot of off-topic posting; often breaking into apnea threads and some folks determined to be personalities. I only made one post and was given some decent advice and some silly advice and worst, some dangerous advice under the guise that equipment companies were slaves to their lawyers and just wanted to play it safe with the specs on masks.

This forum causes posts to hang in the air a bit till they become a part of a thread. I think this is very wise as it allows the info to be culled for dangerous opinions about medical stuff.

I have no idea how to adjust pressure levels on my BIPAP machine and after paying an expert to tell me what is appropriate, suspect I would go back to the expert if I felt they were not spot on. I think mine are as my treatment has proved pretty effective. The mask? I have figured out how to make my mask work... fitment of the first one was HORRIBLE... I was tossed at me when I picked up my machine and they told me to go home and experiment with it and see if I could make it work... just adjust the straps till it quit leaking. I am not convinced that trying on masks in an office really helps that much as a person's face loosens up after they relax and what seems to be a dandy mask when you are in a fitting may leak like a sieve when your face is slack and relaxed in sleep. I really think an effective mask could be designed by some smart person. Maybe new materials or construction methods and that would be my number one goal for researchers as I think this development would go a long way to making PAP treatment a lot more successful and accepted.

Last, before i had my sleep study and got the machine, I had never heard of sleep apnea of a PAP machine. Then I found out that many of my family and friends were using them and was stunned by the sleep apnea epidemic. When you consider sleep disorders contribute to so many other medical issues (heart, blood pressure, diabetes, weight, etc) you would think that doctors would be more on top of this issue.

Personally, I think people should be allowed to have access to the clinicians's set-up menus and be able to make minor adjustments to their pressures -- IF they are well-enough informed and have discussed it with their docs. I know the code for the machine I currently use and have set my own -- and have also NOT done it with a different machine, because I realized I was not thinking all that clearly at the time, and shouldn't be mucking about with the pressures. It is easy enough to go online and find out what the "secret" codes are...usually, at least on the older Respironics, just a combo of two buttons being pushed for a certain amount of time until a certain sound occurs... but seriously, it is easy to think we know more than we do about this. I keep thinking I know, then I find out how much I don't...repeat cycle... So do be care-full.

Don't just go in and change things! There are clinician manuals out there for your machine, but you need to have a good understanding of what happens and why. I use SleepyHead software so I know what is happening, but I was apart of an forum that guided me. They folded and I think this forum took its place! ...I think!!

DanM has given some very detailed information about how things work just above my post. Also, used the search option to see if a thread has been started regarding your issues.

CPAP is not always an easy journey, but persistence pays off. Watch out for expectations as you may not experience the CPAP result you might prefer all at once. My restorative sleep is not where I want it, but it is a heck of a lot better than where I was before I got my CPAP, now BIPAP.