#1 the obvious exception is intranasal morphine, sorry.
#2 in the context of when respiratory depression becomes a problem, if ever, it will not be in chronic opioid abusers. Opiate-naive patients are the ones that must be monitored.
Do you view intranasal K as having potential problems with respiratory depression at the dosage given? My point was that the dosage should be a fraction of the anesthetic doesage, hence oxygen sat and other anesthetic limitations such as psychotropic events should not pose a problem.