This will be dependant on state department of health guidelines.  In most instances a patient whose procedure is cancelled is only coded if the patient gets past the administration desk, is on a bed in the day unit and then something occurs to cancel the procedures.
Examples include:
contraindication - Anaesthetist assesses the patient and they have a condition which causes the procedure to be cancelled ie. patient still on warfarin which was missed, patient has an URTI
equipment breakdown - patient is awaiting procedure and has been admitted, and then there is an equipment breakdown
clinician unavailable - patient is awaiting procedure and has been admitted and then the clinician is delayed or becomes ill and the procedure cannot take place
In these instances, the patient is admitted into the patient administration system which will create an episode to code in VisiCODE once exported.
If the patient is cancelled and does not get past the front desk, then an episode should not be created in the patient administration system and therefore not coded.