juliespoohbear wrote:My RDI is 35.3 AHI is 35.3 AI is 33.1
RDI = Respiratory Disturbance Index
AHI = Apnea/Hypopnea Index
AI = Apnea Index
A respiratory disturbance
is a sleep disturbance that is clearly related to respiratory problems in some way. The main types of events that get counted towards the RDI are respiratory effort related arousals (RERAs), hypopneas (Hs), and obstructive apneas (OAs).
is scored when there is NO AIR moving into or out of your lungs for at least 10 seconds when the EEG says you are asleep. If the belts indicate you were trying to breathe
, the event is scored as an OA. The presumption is that your upper airway is completely collapse and no air can get through. If the belts indicate that you were NOT trying to breathe, the event is scored as a central apnea
and the presumption is that the problem is that your brain simply (temporarily) forgot to send the signal to the diaphragm to inhale.
Exactly what gets scored as a hypopnea
depends on the standard the lab doing the scoring uses. Under Rule 4A, a hypopnea is scored when there is at least a 30% reduction in airflow for at least 10 seconds AND a corresponding O2 desaturation of at least 4%. Such a Rule 4A hypopnea does NOT require an EEG arousal. Under Rule 4B, a hypopnea requires at least a 50% reduction in airflow for at least 10 seconds AND one or both of the following conditions: A EEG arousal OR a corresponding O2 desaturation of at least 3%. Regardless of whether Rule 4A or Rule 4B is used, you can informally think of a hypopnea as when you are attempting to breathe (there is some effort to breathe as measured by the belts) but the air flow is significantly lower than it should be for at least 10 seconds. The usual assumption is that the diminished air flow in a hypopnea is caused by a partial collapse of your upper airway. It's often described as like trying to breathe through a very small straw.
A RERA is something like a "wannabe hypopnea with arousal under Rule 4B." Only the reduction in airflow might not be long enough or deep enough to warrant being scored as a hypopnea under Rule 4B. And a RERA must end with an EEG arousal. It may or may not have a corresponding O2 desat.
The word "Index" means we're looking at the average number of events per hour of sleep as recorded by the EEG
. In other words:
AI = (number of apneas recorded while asleep)/(total sleep time as established by the EEG)
AHI = (number of apneas and hypopnes recorded while asleep)/(total sleep time as established by the EEG)
RDI = (number of respiratory events recorded while asleep)/(total sleep time as established by the EEG)
So here are your numbers and what they mean:
AI = 33.1 means that in an average hour of sleep time, you had about 33 apneas occur. In other words, on average you stopped breathing (in the sense of getting air into your lungs) about every 1.8 minutes since 60/33 = 1.8. (In other words, you had a complete cessation of airflow a bit less than every two minutes.)
AHI = 35.3 means that in an average hour of sleep time, you had about 35 apneas and hypopneas occur. From the AI, we know that about 33 of those events are apneas. Hence the other two events are hypopneas. In other words, on average you stopped breathing (in the sense of getting air into your lungs) OR had a serious about every 1.7 minutes.
RDI = 35.3 = AHI means that all of the respiratory disturbances were either OAs or Hs.
Your diagnosis is going to be severe OSA
or moderately severe OSA
since your AHI > 30. Moderate AHI is defined as
the AHI or the RDI being between 15 and 30.
I am picking up an autopap tomorrow with the prescribed levels between 5-12.
Best of luck in getting some high quality sleep. And make sure that APAP is NOT a Resmed S9 Auto Escape.