Sleep Apnea Support Group

Sleep apnea is a common sleep disorder characterized by brief interruptions of breathing during sleep. People with sleep apnea partially awaken as they struggle to breathe, but in the morning they may not be aware of sleep disturbances.

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AHI

Fehrenbach16
Fehrenbach16
Does your AHI number go up the more hours that you are on the CPAP machine a night? Ex:, slept with mask on for 4.5 hours & had a readout of AHI of 6. Slept with mask on for 1 hour & had an AHI in the morning lower than 6.
keeska
keeska
AHI is the number of times you had apnea/hypopnea episodes. The longer the period of time you use CPAP, the more episodes will be counted.

Its sort of like adding coins to a gallon jar every 10 minutes. If you add coins for an hour, you'll have six coins. If you add coins for six hours, you'll have thirty-six coins.

Just a little analogy.
Tez62
Tez62
Fehrenbach16, AHI is the average number of times we stop braething per hour for 10 secs or more, so its the total number of apnea's you have divide by the total number of hours. So in your case you would have had 27 apneas in the 4.5 hours which would equal 6.
The 1 hour one would depend on what time you put your mask on, the clock in the CPAP runs from 12 noon for 24 hours and then clears the data for the next day, so if you had it on for 6 hours then another hour within the same 24 hour period, it would divide your total apneas by 7 hours.
There isnt really a correct answer to your question, what concerns me more is that your AHI is still around 6, it should be below 5 and as low as possible. You are basically still falling in the mild sleep apnea range so your treatment may not be as good as it should. How do you feel during the day? Do you have the same symtoms you had before CPAP? What type of mask are you using? Nasal pillows, a nasal mask or full face mask? You could be getting leaks.
Thewino
Thewino
Farenbach,

The AHI is calculated by: the number of events by the number of hours you slept.

Assuming you went to sleep immediately, your one hour of sleep AHI and your 4.5 hours of sleep should be close.

The problem is that with only one hour of sleep, people don't usually fall asleep right away and your machine doesn't know you aren't sleeping so it usually has extra events during the first hour.

You can look this up by putting your CPAP machine SIM card in your computer and running it through the free software called 'SleepyHead'. Then, you will know for a fact if you are having extra events counted during the first hour.

Be well,
TheWino