If sleep apnea is present, it will likely be pursued as one of the results of the ENT evaluation. It is unusual for a child of 8 to be complaining of feeling tired during the day. Now, relative to the attentional and hyperactivity issues, they are likely a separate thing, not related to either ENT problems or sleep apnea.
It's a fairly new study area, but do the research and get some more information, and get an assessment from a professional - perhaps discuss with the pediatrician monitoring her ADHD. Good luck.
diagnosis and ADHD diagnosis. I was told that the symptoms look similar and unless you rule out sleep apnea i dont thiki its
fair to the child to diagnos as ADHD. you should consult a specialist not just pediatrician.