Floor or roof mounting what, exactly?
The great thing about overhead suspension is that it keeps the kit (whatever it is) off the floor! In the theatre it has the added advantage of being able to be moved around (re-positioned) to suit the surgical procedure in question.
If we are talking about moveable ceiling mounted pendants, I would always try to go for two in each theatre, and get as much on them (power outlets, medical gases
etc.) as possible.
Ceiling suspended pendants should not affect air flows any more than the main operating lights will (and to a certain - but negligible - extent,
do). Just pay special attention to the ceiling plan design (hopefully
before the rooms are constructed).
Either way, any properly designed theatre should be able to overcome any of the points you mention.
