And if they are and yet still contain fecal matter, how does going in the next day help? Your appointment is still after someone else's. Do they use a new scope?
Theoretically, some bacteria could have died overnight, which would be good. In general, simple instruments constructed of stainless steel or other solid non-porous materials are easy to wash off and autoclave. Complicated constructions in which multiple parts fit precisely inside other parts constructed of different materials are not easy to wash and autoclave. Scope manufacturers would be encouraged to design more sensibly if physicians could be held accountable for cross-contamination. This would require a more aggressive regulatory regime.
I am trying to make sense of the original post while stipulating that the claim about it not being harmful is true. Assuming only sterile fecal matter is left on the device, how does having an appointment the next day help?
He seems to be suggesting that the fecal matter can be avoided by a gap of 16 hours versus a gap of (say) 30 minutes. I'm at a loss for the mechanism by which this might occur.
I work on the video side of things and know nothing about the mech eng part. What I can tell you is that during the day there is definitely fecal matter in the scope one case to another during the day after after autoclave and sterilization. The first case of the day, the scope is clean. I don't know what's different about overnight processing in the sterile processing department. And I've seen this at many hospitals. There's been some startups that have tried sheaths to cover the scope but could not make it work.
The difference you cite between the per-patient and daily cleaning, disgusts any human who learns of it. The only studies showing that sort-of clean scopes are safe were funded by the scope manufacturers. This is problematic.
There are design issues currently being worked on to minimize crevices and spaces where bacteria may remain (redesign) or avoid the issue completely (design and implement disposable endoscopic heads)