From my experience, it takes a while... BUT I usually walk out with one of the surgeons or PAs so I don't get to see what happens. Once the patient is wheeled out of the OR, many things get stripped down.
Gowns, surgical towels, protective gear, etc gets properly disposed of...
Tables of instruments have to get wrapped appropriately and sent off to autoclave, etc to be sterilized.
I usually walk out when the cleaning people come in. The bring equipment, even mops...
SO after all of that I'm going to say it takes at least 20 minutes to clean the room. It then takes more time to set up for the next surgery. Hope this helps. I don't have a ton of clinical experience yet (only an MSII), but that's my observation.