Abstract: A device capable of providing non-invasive, accurate estimates of central venous pressure. This diagnostic device is particularly useful with patients suffering from cardiac disease.

Abstract: An overvoltage limiting circuit having first and second terminals to produce a temperature-stable voltage proportional to an overvoltage condition. The overvoltage limiting circuit includes a first transistor having a first terminal connected to the first terminal of the circuit, a second terminal kept at a reference voltage relative to the second terminal of the circuit, and a control terminal coupled with the second terminal of the circuit through equivalent resistor means whose value depends on the value of the temperature-stable voltage so that the first transistor has a temperature-stable breakdown voltage.

Abstract: A device capable of providing non-invasive, accurate estimates of central venous pressure. This diagnostic device is particularly useful with patients suffering from cardiac disease.