An apparatus for intra-aortic balloon monitoring and leak detection

Claim 1

An apparatus for monitoring the operation of an intra-aortic balloon (12) inserted into the aorta (26) of a body (28) in which the balloon (12) includes an electrical conductor (22) therein for extending out of the body (28) comprising an electrode (32) adapted to be affixed to the exterior of the. body (28), characterized by an electrical current source (42; 116) adapted to be connected to the electrode (32) and to the electrical conductor (22), and an impedance measuring means (30; 118, 120) electrically connected to the electrode (32) and the electrical conductor (22) for measuring the impedance (Z; R X ) of the balloon (12) for monitoring its operation.

Claim 2

An apparatus for monitoring the operation of an intra-aortic balloon (12) inserted into the aorta (26) of a body (28) in which the balloon (12) includes an electrical conductor (22) therein for extending out of the body (28) comprising an electrode (32) adapted to be affixed to the exterior of the. body (28), characterized by an electrical current source (42; 116) adapted to be connected to the electrode (32) and to the electrical conductor (22), and an impedance measuring means (30; 118, 120) electrically connected to the electrode (32) and the electrical conductor (22) for measuring the impedance (Z; R X ) of the balloon (12) for monitoring its operation.

Claim 5

The apparatus according to any one of claims 1 to 3, characterized by means (112) limiting the electrical current flowing between the electrode (32) and the electrical conductor (22).

Claim 6

The apparatus according to any one of claims 1 to 4, characterized in that the current source is an alternating current source (42, 44, 46) and the frequency of the alternating current is above the range of cardiac susceptibility.

Claim 9

An apparatus for monitoring the operation of an intra-aortic balloon (12) inserted into the aorta (26) of a body (28) in which the balloon (12) is inflated and deflated with gas by a control system and in which the balloon (12) includes an electrical conductor (22) therein extending out of the body (28), comprising an electrode (32) adapted to be affixed to the exterior of the body (28), especially for the purpose of monitoring the inflation and deflation of, and detecting a leak in, the balloon (12) characterized by an electrical subassembly (40) including an alternating current impedance measuring circuit connected to the electrode (32) and the electrical conductor (22) for providing a current path through the body (28) across the balloon (12), a direct current power supply (42) connected to the subassembly (40) electrically isolated from earth ground and providing power to the measuring circuit, a sinusoidal oscillator (44) providing an alternating current signal to the measuring circuit, but isolated therefrom by a first transformer (46), an alternating current to direct current converter (50) connected to the output of the measuring circuit, but isolated therefrom by a second transformer (48), and a signal processor (52) connected to the output of the converter (50) for providing an output (54) proportional to the measured impedance, said output (54) of the processor (52) connected to the gas control system (20) for deactivating the control system (20) when the measured impedance (Z) falls below a predetermined level.

Claim 10

An apparatus for monitoring the operation of an intra-aortic balloon (12) inserted into the aorta (26) of a body (28) in which the balloon (12) is inflated and deflated with gas by a control system and in which the balloon (12) includes an electrical conductor (22) therein extending out of the body (28), comprising an electrode (32) adapted to be affixed to the exterior of the body (28), especially for the purpose of monitoring the inflation and deflation of, and detecting a leak in, the balloon (12) characterized by an electrical subassembly (40) including an alternating current impedance measuring circuit connected to the electrode (32) and the electrical conductor (22) for providing a current path through the body (28) across the balloon (12), a direct current power supply (42) connected to the subassembly (40) electrically isolated from earth ground and providing power to the measuring circuit, a sinusoidal oscillator (44) providing an alternating current signal to the measuring circuit, but isolated therefrom by a first transformer (46), an alternating current to direct current converter (50) connected to the output of the measuring circuit, but isolated therefrom by a second transformer (48), and a signal processor (52) connected to the output of the converter (50) for providing an output (54) proportional to the measured impedance, said output (54) of the processor (52) connected to the gas control system (20) for deactivating the control system (20) when the measured impedance (Z) falls below a predetermined level.

Claim 13

The apparatus of any one of claims 8 to 10, characterized in that the signal processor (52) includes first and second comparators (72, 74) for the generation of signals when measured impedance increases above a predetermined level and when the measured impedance decreases below a different predetermined level, respectively.