SURGICAL PROCEDURES performed on two or more patients that overlap in their start and finish times, but the critical portions or those activities which require the skill and expertise of the primary surgeon do not overlap. The primary surgeon initiates and participates in another operation when the surgeon has completed the critical portions of the first procedure and is no longer an essential participant in the final phase of the first operation.

SURGICAL PROCEDURES in which critical portions of the operation for which a single surgeon is responsible are being performed on different patients, and in different rooms, during the same period of time.