Abstract: The present invention involves a patient support system. The support system has a fluid bladder and a container. The container has an air pump, a manifold and a CPR dump system. The CPR dump system has a manifold aperture, a plug positioned in the manifold's aperture, a rod interconnected to the plug and protruding from the container's opening, a magnetized alignment apparatus, and a magnetized stop mechanism. The magnetized stop mechanism fastens to the rod and magnetically attaches to the magnetized alignment apparatus which insures the plug is lodged in the manifold's aperture. When a user wants to expeditiously deflate the inflatable fluid bladder, the user pulls on the distal end with sufficient force to detach the magnetized stop mechanism from the magnetized alignment apparatus thereby the plug dislodges from the manifold aperture and allows the inflatable fluid bladder to deflate within a predetermined time frame.

Abstract: A circuit for limiting a voltage appearing at an output terminal to a preselected range of voltages including a plurality of field effect transistors connected in series between first and second levels of potential to form a voltage divider network of the potential difference between the first and second levels of potential; an output field effect transistor having source, drain, and gate terminals, the source and drain terminals being connected between the first level of potential and the output terminal; and apparatus operating in response to a voltage provided by the voltage divider network for biasing the gate terminal of the output field effect transistor to transfer the first potential to the output terminal so long as the first potential remains below a predetermined value and for transferring the first potential less the switching voltage of the output field effect transistor to the output terminal if the first potential is greater than the predetermined value.