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Lauren is a Certified Sleep Science Coach with extensive experience researching and testing a wide variety of sleep products.
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People with obstructive sleep apnea (OSA) stop breathing for brief intervals during sleep due to blocked or collapsed airways. Continuous positive airway pressure (CPAP) machines are commonly prescribed to treat the condition following the results of a sleep apnea test. The devices deliver pressurized air to help normalize breathing. The right amount of pressure is critical to effective CPAP therapy, as pressure that is too low or too high can create adverse side effects.
We’ll discuss how CPAP pressure is measured and the various factors that determine pressure needs. We’ll highlight signs and symptoms that suggest your pressure level might need adjusting, in which case it’s important to contact your doctor. Pressure settings should only be changed under the guidance of a medical professional.
Pressure in a CPAP machine is measured in centimeters of water pressure (cm H2O). Settings vary based on the device, but most CPAP machines have a pressure range of 4 cm H2O to 20 cm H2O. Some machines go as high as 30 cm H2O, but this is less common. The average pressure setting for people with OSA is around 10 cm H2O.
A CPAP titration study is the most common method used to determine an appropriate pressure level. Similar to a sleep study, the assessment is usually done overnight at a sleep center or hospital. Sensors are attached to your body to monitor oxygen levels, breathing, heart rate, brain waves, and body movements. A physician or sleep specialist calibrates CPAP pressure levels until the lowest amount of pressure needed to keep airways open is determined.
The apnea-hypopnea index (AHI) assesses how many times a person stops breathing or breathes shallowly while asleep, which helps medical professionals determine CPAP pressure settings. Most modern CPAP machines keep track of your AHI, which lets you and your doctor know if your pressure level needs to be modified.
You will also be fitted for a CPAP mask during the study, which is crucial for effective treatment. CPAP masks come in a variety of styles, including full-face masks, nasal masks, and nasal pillows.
A number of factors determine the severity of OSA and a person’s appropriate CPAP pressure setting. Some are anatomical, while others relate to lifestyle and sleep habits.
Proper CPAP pressure levels help alleviate conditions associated with sleep apnea, such as snoring and sleep disturbances. If you’re not experiencing better sleep quality after CPAP therapy, you will probably need to consult with your doctor about adjusting your pressure settings. Here are telltale signs that your pressure is either too low or too high:
If you continue to have issues with pressure settings on your device, your doctor might prescribe an automatic positive airway pressure (APAP) machine. This device automatically changes pressure levels based on a user’s breathing patterns. The machine starts at a low setting and then increases according to changes in breathing and airway resistance.
Even though APAP machines automatically adjust pressure levels, a physician still needs to prescribe an ideal pressure range suited to your needs. If the range is off, you may experience adverse side effects.
If you consistently experience discomfort during CPAP therapy, or you are not noticing any improvements in your sleep or health, then you probably need to adjust the pressure settings. Persistent fatigue, loud snoring, mask leaks, and difficulty exhaling all indicate suboptimal pressure levels. An above-average AHI level suggests that your pressure setting may be too low.
A physician determines proper pressure settings based on your CPAP titration study and AHI. Your pressure might need to be adjusted later if you lose or gain significant weight, change your sleep position, or start taking certain medications. Always speak with your doctor if you suspect your pressure level needs fine-tuning.
If you think your pressure level needs adjusting, contact your doctor’s office and bring your CPAP machine to the appointment. Your doctor will evaluate data from the device and make changes as needed. Pressure settings should only be changed under medical supervision.
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