Sleep problems after anasthesia complications

My 14 year old daughter had her tonsils and adenoids removed. Following surgery she had a terrible reaction to anasthesia (or that's what they think). She was in ICU for three nights. At this point it has been 3-4 weeks since her surgery and she is having one to two episodes every night where her breathing becomes very shallow and very rapid...she is totally asleep. This also happened while in the hospital (both awake and asleep) but is now only happening while she is sleeping. We have to wake her to get her out of it. While in the hospital it went to the point of all of her joints locking up--hands fisted--posturing of her mouth and lack of sensation around her mouth, difficulty visually focusing her eyes--they had to give her two doses of adavan to get her out of it. I am sleeping with her each night so that I can wake her when it happens. We are scheduled for a sleep study this Friday night and I am hoping for some answers. I have had difficulty finding any information on this condition online. The drug she was given for anasthesia was propofol-diprivan. If anyone has any ideas about what might be happening, I would love to hear them!!!