Flow rate control for a cooled medical probe assembly

A system for using a plurality of medical probe assemblies to deliver energy to a patient's body, the system comprising:

• a generator in operative communication with each medical probe assembly of the plurality of medical probe assemblies, the generator comprising a generator controller and memory storing a set of parameters for a treatment procedure;
• and
• a plurality of cooling systems, each cooling system associated with one medical probe assembly of the plurality of medical probe assemblies, each cooling system comprising:
• a pump assembly including a control unit having a controller, a motor, and a pump head driven by the motor;
• a lumen for delivering a cooling fluid to a distal end of the medical probe assembly associated with the cooling system;
• a tubing for conveying the cooling fluid from a fluid reservoir to the lumen, the tubing extending through the pump head;
• and
• a flow sensor for sensing a flow rate of the cooling fluid,
• wherein the pump head is disposed between the fluid reservoir and the medical probe assembly associated with the cooling system to pump the cooling fluid from the fluid reservoir to the lumen through the tubing,
• wherein the flow sensor is disposed between the pump head and the medical probe assembly associated with the cooling system to sense the flow rate of the cooling fluid,
• wherein each pump assembly is supported on the generator, and
• wherein each medical probe assembly of the plurality of medical probe assemblies comprises:
• at least one probe having an elongate member with a distal region and a proximal region, the distal region comprising an electrically non-conductive outer circumferential portion, and
• an electrically and thermally-conductive energy delivery device extending distally from the electrically non-conductive outer circumferential portion for delivering one of electrical and radiofrequency energy to the patient's body, the energy delivery device comprising a conductive outer circumferential surface and an energy delivery device distal end that forms the distal end of the medical probe assembly to which the cooling fluid is delivered,
• wherein each flow sensor of the plurality of cooling systems outputs a flow rate signal to the respective controller, wherein the respective controller is configured to process the flow rate signal to obtain a processed flow rate signal, and wherein the respective controller is configured to output the processed flow rate signal to the generator controller,
• wherein the generator uses the generator controller to determine whether to adjust the speed of the respective motor based on the processed flow rate signal and the set of parameters for the treatment procedure such that the cooling system is a direct measure, closed loop feedback system.