A method of irrigating a surgical site and aspirating fluid from the surgical site. The method includes directing a fluid through an aspiration conduit in a phacoemulsification hand piece using a vacuum pressure created from a pump in the hand piece interfacing with the aspiration conduit and directing an irrigation fluid through an irrigation conduit in the hand piece using a pressure created from the pump interfacing with the irrigation conduit. The method also includes increasing an irrigation fluid flow through the irrigation conduit by activating the pump in the hand piece, detecting a pressure associated with a surgical site using a sensor, and controlling intraocular pressure (IOP) by adjusting the pump speed based on the detected pressure.