A catheter system for controlling the body temperature of a patient by modifying the temperature of blood flowing within a blood vessel of the patient. The catheter system comprises a catheter body having a heat exchange region in contact with the blood; and a temperature probe having a distal end that extends from the catheter body, thereby monitoring the temperature of blood flowing within the blood vessel.

Apparatus, consisting of a power supply having a first electrical connection to a relatively high voltage source and connectable to ablation circuitry in a catheter via a second electrical connection. There are rechargeable first and second subsidiary power sources in the power supply. The apparatus also has a control unit, and a first switch alternately connecting the ablation circuitry to the first and second subsidiary power sources responsively to control signals from the control unit. The apparatus also has a second switch alternately connecting one of the first and second subsidiary power sources to the high voltage source for recharging thereof responsively to the control signals while the one of the first and second subsidiary power sources is disconnected from the ablation circuitry and another of the first and second subsidiary power sources is connected to the ablation circuitry by the first switch.

The invention comprises a system for securing an implant to a bone comprising an implant which is affixed to the bone, a grout or bone cement comprising a composition that cures in an exothermic reaction and which is capable of securing the implant to the bone in a cured state, and a tester which measures temperature over time to detect a rate change of temperature and uses a novel discrete differentiator circuit to determine when the composition reaches cure.

A surgical instrument includes a transducer configured to produce vibrations at a predetermined frequency. An ultrasonic end effector extends along a longitudinal axis and is coupled to the transducer. The ultrasonic end effector comprises an ultrasonic blade and a clamping mechanism. A controller receives a feedback signal from the ultrasonic end effector and the feedback signal is measured by the controller. A lumen is adapted to couple to a pump. The controller is configured to control fluid flow through the lumen based on the feedback signal, and the lumen is located within the ultrasonic end effector.