A method for operating a surgical system including a control unit having a vacuum sensor and/or a flow rate sensor, the method including placing a handpiece in an operative relationship with an eye for a surgical procedure and thereafter supplying irrigation fluid to the handpiece while applying a vacuum to the handpiece to aspirate the irrigation fluid from the eye through the handpiece. During fluid aspiration, a vacuum level and/or flow rate is sensed which corresponds to an occlusion of the handpiece and from the sensed vacuum level and/or flow rate, a duration of the occlusion is determined. In response to the determined duration of occlusion, at least one of the handpiece parameters is varied.