CPAP 101

How to Better Understand Your CPAP Results

Today’s contemporary CPAP devices are incredibly capable and sophisticated machines that can deliver a wide range of specific CPAP results in the form of data each morning. It is important to monitor and understand the data that your CPAP machine records every night. While devices vary by complexity, function and price, the best CPAP machines include several important statistics about your nightly sleep patterns. Let’s look at the unique metrics you should track while undergoing CPAP therapy.

guide to cpap results

Your Sleep Duration CPAP Results

The first piece of information that all CPAP devices manage is the duration of CPAP usage over the course of a night, week, month, or year. The readout verifies that you’re using the CPAP as intended. This is why it is important to keep a close eye on your CPAP readings.

AHI Severity Index

The Apnea-Hypopnea Index (AHI) demonstrates the user’s level of Obstructive Sleep Apnea (OSA) by creating a “number of OSA episodes per-hour” figure. In general, 0-5 events per hour is normal, 5-15 is mild OSA, 15-30 indicates moderate OSA, and anything above 30 equates to severe Sleep Apnea. If you see a steady rise in OSA events as indicated by the AHI figure, consult with your sleep specialist right away.

Leak Rate

CPAP devices will leak, but it is intentional. As the user breathes, they exhale carbon dioxide and must be exhausted to prevent a dangerous respiratory situation. Each CPAP therapy mask features a set of specially-designed holes that vent (leak) carbon dioxide as the user exhales. Most machines will show a “normal” leak rate if the amount registers 20-24L/minute or less. Anything above that and you’re likely dealing with a poor-fitting mask.

Pressure Statistics

Your CPAP results will show the percentage of time the Auto Adjust feature worked to bring your pressure levels up to the maximum setting. If your CPAP adjusts the positive airway up to the maximum level of pressure, more than 10% of your sleeping hours, you might want to increase the ceiling pressure of the device. You can consult with your sleep specialist to re-calibrate the CPAP, if necessary.

Other Indices

Beyond pressure statistics, average hours of use, AHI indices, your CPAP machine can also deliver information such as:

  • Number of spontaneous arousals per hour. This means any non-respiratory events detected during the night that may indicate other health issues.
  • RDI, or Respiratory Disturbance Index. The RDI includes respiratory issues like snoring, hyperventilation, desaturation, and more.
  • PLM figures, or periodic limb movements. Periodic Limb Movements are repetitive limb movements that can disrupt sleep. Your CPAP machine can analyze this movement to identify other concerns, including chronic PLM.

Your CPAP device is designed to keep watch on your sleep throughout the night. This data can help you and your doctor make informed decisions about your respiratory health and treatment regimen. For more information about CPAP devices, including those that offer the latest in diagnostic reporting capability, contact the experts at today!


  1. Joann Porter Reply

    I don”t understand the numbers 0.7 is how many times in a hour period and 1.0 in a 4 hour period i dont understand what that means could you please help me on the numbers to better understand been waking up with headaches ever since i started using machine
    Thank you

    • AHI is expressed in terms of numbers and decimals and is a composite score of a couple of different factors. These can include the number of times you stop breathing during the night, and the number of times blood oxygen drops to an unsafe level. It’s hard to say what your AHI score is made up of unless your machine keeps track of the individual events. Just know that a 1.0 or a 0.7 AHI is very good if that’s what you’re referring to. It means your therapy is working well.

      • i have an older Phillips Respironics. the AHI reads 2.8 and 2.7 on 30 day average. We are in CO. so drier here than where I usually live. What ramp range and ramp time is usually good? Any other readings to be sure of?

        • Hi Barbara, the ramp is a comfort setting therefore, you can manipulate this setting to your comfort. The AHI, readings are considered to be normal as long as it is listed at under 5, great job!

          Since Colorado has a drier climate, you may need to add humidification, or increase your humidity settings, if you are currently using a humidifier.

          For further questions, or concerns, please feel free to reach us at: 1-800-356-5221.

          Have a great day!

  2. Lillian Vargas Reply

    i was reading 4 AND 5 ON MY CPAP events per hour.
    On vacation now my readings have increased to 10 and 12.5.
    Could it be the different air flow in the room?
    I live in Chicago, IL
    Now in Florida

    • Hi Lillian, I don’t know that the change in your readings would be related to a different air flow in the room. Are you currently using a standard CPAP machine? Did you have any alcoholic drinks that you normally don’t have? If so this could have an effect on your readings. There may be other causes for the change in your readings as well.

      I would encourage you to speak with your doctor about the difference in your readings to see if he/she may have any input.

      If you would like to speak with us further, please feel free to reach us at: 1-800-356-5221, or you may e-mail us at:

      We wish you the best!

  3. Rachel Murray Reply

    My son is two and his total hours used is 7685 and used hours are 3021 is that good ?

    • Hi Rachel, my apologies for the delayed response. The total hours used is how much usage is on the machine, kinda like how many hours the machine is actually turned on. The used hours would be how many hours you are actually receiving therapy with the mask on.

      Unfortunately, i’m not able to confirm if the hours your son has is good, or not. This is something that you would need to speak your son’s doctor about for data interpretation. As the used hours could be good, or bad depending on the usage threshold, which is the minimum time that he must use his device in order to be compliant.

      For further questions, or concerns, please feel free to reach us at: 1-800-356-5221, or you may e-mail us at:

      Enjoy your day!

  4. My reading was 1.7 of AHI. Does it a good result? I’d like to know that CPAP machine needs to be adjusted or not?

    • Hi Bonnie, when your AHI, is below 5, it is considered normal. It sounds like your settings are working well for you.

      Please feel free to contact us at: 1-800-356-5221, or e-mail us at: with further questions, or concerns.

      We wish you continued success!

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