A system for exchanging heat with primary coolant flowing through an intravascular catheter (12) or externally-applied pad (18) to warm or cool a patient. A secondary heat transfer element (24) can be engaged with a primary heat transfer element (22) and is not grounded when the primary heat transfer element (22) is fully engaged with the secondary heat transfer element (24) during operation. In contrast, the secondary heat transfer element (24) is grounded when the primary heat transfer element (22) is at a predetermined disengaged position relative to the secondary heat transfer element (24).