The events are measured in a point system called an apnea hypopnea index. An index below five indicates no sleep apnea. Mild OSA: AHI of 5-15. Involuntary sleepiness during activities that require little attention, such as watching TV or reading Moderate OSA: AHI of 15-30. Involuntary sleepiness during activities that require some attention, such as meetings or presentations. Severe OSA: AHI of more than 30. Involuntary sleepiness during activities that require more active attention, such as talking or driving. [3] X Research source Sleep clinics typically do not recommend that new CPAP users change their pressure settings until they’ve had their first sleep study and used the prescribed pressure settings for several weeks at minimum. While you are in the sleep lab, the doctor or sleep specialist may also:[4] X Trustworthy Source National Heart, Lung, and Blood Institute Research and education center within the National Institutes of Health Go to source Measure your activity levels and movement as you sleep Record your brain activity, eye movements, blood pressure, heart rate, and blood oxygen levels Fine-tune the fit of your mask and the air pressure settings
You gain or lose weight You are extra tired You have had a few alcoholic drinks You are on prescribed sedatives You have sinus congestion You are using a different mask You are at a different altitude You have jet lag You change stages in your sleep cycle
An auto-CPAP machine is likely the best long-term option, since your air pressure needs change day by day (and even hour by hour) as you sleep. A one-time titration study within a sleep clinic cannot account for various personal changes that impact air pressure needs, such as: what sleep stage you’re in, sleeping position, what you eat / drink, your body weight, and various drugs you take. Auto-adjusting helps prevent you from swallowing air at times when your standard pressure is too high. Swallowing air can make people feel bloated and disrupt their sleep.
A data recording machine usually stores patient data that is viewable on the machine or from a removable “smart card” or other memory card on your computer. A data recording machine records several variables that help determine optimum air pressure, including your Apnea/Hypopnea Index or AHI. In contrast, a non-data recording machine records very little or no health information or variables, so you’re kind of adjusting these machines by feel. Contact the manufacturer to obtain patient and clinician manuals to get a better understanding of your machine.
Most CPAP machines have a range of adjustment from 4cmH20 (the lowest pressure) to 20cmH20 (the highest pressure). For the Respironics CPAP machine, you need to highlight the Setup option on the display screen and then hold down the ramp and wheel buttons at the same time for a few seconds until you hear a few beeps. After the beeps, access the Setup option and scroll down the menu to select the Auto Max and the Auto Min options. These represent the maximum and minimal pressures the machine oscillates between during the night. Try increasing the Auto Min setting first (so it’s closer to the Auto Max setting). After adjusting very slightly, leave it at that for a few weeks to adequately evaluate the improvement, or lack of sleep quality and daytime alertness. You may have to increase both the Auto Max and Auto Min pressure settings, but use your AHI as a guide of how you’re responding in the night while sleeping.
To change the settings on a non-data recording Respironics CPAP machine, follow the instructions above on how to change them on a data recording machine. The main difference is that you won’t be able to access the Data option beforehand to see your AHI. In the vast majority of cases, people unhappy with the settings on their CPAP machine want to increase the pressure in order to get more air. In a minority of cases, people may want to lower the settings because the pressure is too great and creating noisy leaks from their masks, causing bloating or leading to excessive dry mouth.
Changing air pressure too much at a time can decrease the effectiveness of your therapy and potentially lead to dangerous health complications. Always start by raising your Auto Min setting, which is often set between 5-8cm/H20, and then gauge effectiveness before changing the Auto Max setting — usually set at around 15cm/H2O. Even if your have access to your AHI, keep a written log of how you feel each morning, afternoon and evening. Don’t make dramatic lifestyle / dietary changes that could change your optimum air pressure and confuse you while altering settings to your CPAP machine.
Before changing your pressure settings on your Respironics CPAP machine, ask your doctor or sleep clinician to try a different type of mask. Switching to a more comfortable mask may necessitate raising or lowering your pressure settings depending on it’s design. For many people, having an Auto Min setting greater than 10cm/H20 starts to cause uncomfortable side effects such as bloating, belching and dry mouth.
If it’s a hassle or too great of an expense to see your physician, call and talk to their secretary or nurse and explain that you want to change the settings and need a faxed prescription. Alternatively, call the medical equipment company and ask them to contact the doctor’s office on your behalf. Without proper medical training and licensing, changing the settings on a CPAP device can get you into legal trouble, so make sure you know the law in your area.
