The present disclosure is directed to a fluid cooled ultrasonic surgical instrument and related systems and methods of use therefor. In some embodiments, the disclosed ultrasonic surgical instrument is adapted for used within an insufflated cavity or pneumoperitoneum of a patient. The instrument includes a housing having an elongate shaft, a waveguide disposed at a distal end of the shaft, a coolant inlet port defined in an outer surface of the housing, and a coolant pump disposed within the housing and configured to move coolant from the coolant inlet port to the waveguide. During use, insufflation gas from within the pneumoperitoneum is drawn into the instrument shaft by the coolant pump, and blown over the waveguide to provide cooling. The delivery of ultrasonic energy and activation of the pump may be controlled by a processor in response to user input and waveguide temperature.