A surgical system that is able to sense the onset of an occlusion or other surgical event as well as the instant an occlusion breaks. To help avoid overheating of the tip, the system determines a temperature of an eye using irrigation flow rate and reduces the power to the handpiece automatically if an overheating situation is predicted. Alternatively or in addition, the system monitors the power drawn by the handpiece, which is indicative of the cutting load on the tip, and automatically adjusts the power or stroke of the tip to compensate for increased loads on the tip.