Searched the archives....didn't see anything on this issue recently, so here's one for the SRNA's to discuss first. (Army, Mike, MJ, others...please hold off for now)

18 yo male, 77kg
NKDA.
Negative PMH.
No meds.
S/P Tympanoplasty...case lasts about 50mins. Uncomplicated.
GETA. No issues documented.
No issues phase 1 in PACU.

You are called by the Ambulatory RN to evaluate him in the phase 2 area for "low sats". (Now 2 hours postop).
This is not your patient and the CRNA who did the case has gone home for the day.
As you enter, he is watching TV, appears in NAD. Mom is at bedside.
VS: 106/65 P 78 RR 24 O2 Sat 88% (Room air)

Says he's "tired" but otherwise feels okay. Pain controlled. Doesn't feel SOB but got "lightheaded" when he went to walk to bathroom across the hall. Color looks okay. Voice sounds normal.

Where do you start? What are you thinking? What are your differentials?
The Amb RN's were ready to DC this patient home. The dept is busy and they need the room. Surgeon wants to know why his patient is still here.