How to find the optimum pressure
on your constant-pressure CPAP machine
by SuperSleeper and the members of the Apnea Board Forum
Get A Sleep Study First
Consult With Your Doctor
Consider Upgrading To An Auto-CPAP
Adjust Your CPAP At Your Own Risk
What Type Of CPAP Do You Have?
Adjusting CPAPs That Are Not Fully Data-recording
- Adjust your CPAP pressure in small, incremental changes. We recommend that you do not change your pressure more than 0.5 cm/H20 at any one time. Changing pressures too much can decrease the effectiveness of your therapy and may lead to unintended and potentially dangerous health complications.
- Give it time to work. After you make a pressure change, don't make any additional changes for a week or two.
- Keep a written log of how you feel each morning, afternoon and evening. Note any pain, daytime sleepiness, changes in energy level or mental alertness. Make sure you listen to your body.
- Don't change other variables in your lifestyle which may influence your pressure needs. If you change what you eat and drink, where you sleep, your exercise level, what drugs you take or other non-pressure-related factors, you'll have no way of knowing whether your improved wakefulness and energy was caused by your lifestyle change or your CPAP pressure change.
At some point during your experimentation with pressure changes, you will note "diminishing returns" where you actually start feeling worse, not better. At this point, you should adjust the pressure back to the last pressure setting that made you feel the best. This will be your optimum CPAP pressure for a constant-pressure machine with no data-recording capability. Monitor how you feel from this point forward and if your wakefulness or energy level changes, re-evaluate your pressure level again.
Adjusting CPAPs That Are Fully Data-recording
It's generally best to get your AHI below 5.0, but some are able to get it below 3.0 or lower, which is even better.
The Apnea/Hypopnea Index (AHI) is the frequency of abnormal respiratory events per hour of sleep. These events are classified as Apneas or Hypopneas. Apnea is when breathing (airflow) stops for 10 seconds or more. Hypopnea is a partial blockage of airflow resulting in arousal and a possible drop in oxygen level. An AHI of 45 would indicate that the patient is experiencing complete or partial airflow blockage 45 times per hour.
The generally accepted ranges are:
AHI < 5 per hour = No Sleep Apnea
AHI 5 to < 15 per hour = Mild Sleep Apnea- (some say that 5-10 would be called "borderline OSA")
AHI 15 to < 30 per hour = Moderate Sleep Apnea
AHI > or = 30 per hour = Severe Sleep Apnea
Again, take it slowly, recording your nightly AHI levels after each pressure change, and don't make large, sudden changes as you attempt to decrease your AHI to the lowest level possible. The AHI will help give you a more precise way to judge the effectiveness of your adjustments.
For instructions on how to enter the Clinician Setup Menu (to change pressure) on your specific CPAP machine, go to our CPAP Clinician Manual Page, where you can obtain the Clinician Setup Manual for your machine.
Good luck and sleep well.
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