Impedimed Limited

Aorora Technologies Pty Ltd

Intesection Medical, Inc.

Intersection Medical, Inc.

Scott Chetham

Andrew William Ward

James McFarlane Kennedy

Paul J Erlinger

Ian John Bruinsma

Christopher Newton Daly

Alfonso L De Limon

Leigh Cordwin Ward

Tim Essex

Eniko Srivastava

Apparatus for performing impedance measurements on a subject. The apparatus includes a first processing system for determining an impedance measurement procedure and determining instructions corresponding to the measurement procedure. A second processing system is provided for receiving the instructions, using the instructions to generate control signals, with the control signals being used to apply one or more signals to the subject. The second processing system then receives first data indicative of the one or more signals applied to the subject, second data indicative of one or more signals measured across the subject and performs at least preliminary processing of the first and second data to thereby allow impedance values to be determined.

Monitoring system

A method of performing impedance measurements on a subject. The method includes using a processing system to determine at least one impedance measurement to be performed, and at one electrode arrangement associated with the determined measurement. A representation of the arrangement is displayed so the impedance measurement can be performed once the electrodes have been arranged in accordance with the displayed representation.

A method of determining an indication of the hydration status relating to a subject. The method includes determining a measured impedance value for at least one body segment, and then; for each body segment, using the measured impedance values to determine at least one indicator at least partially indicative of a level of extracellular fluid. Indicators can then be used to determine an indication of the hydration status.

Hydration status monitoring

A method for determining biological indicators, the method including, in a processing system causing at least one radiation attenuation measurement to be performed and determining at least one first biological indicator using determined radiation attenuation. In addition to this, method includes causing at least one impedance measurement to be performed and determining at least one second biological indicator using a determined impedance measurement.

Measurement apparatus

Non-invasive devices and systems to determine tissue wetness/hydration based on relative changes in subsurface resistivities in tissue below an electrode array applied to a human body across different frequencies. For example, these a sensor including arrays of current-injecting and voltage-sensing electrodes may be placed on a subject's back to determine lung wetness. Systems and methods for determining tissue water content, systems and methods for determining lung wetness, sensors for determining relative changes in subsurface resistivities across frequencies and systems and methods to determine which arrays of electrodes in a sensor to use to determine relative changes in subsurface resistivities across frequencies are all described.

Methods for determining the relative spatial change in subsurface resistivities across frequencies in tissue

Apparatus for use in performing impedance measurements on a subject. The apparatus includes a processing system for causing a first signal to be applied to the subject, determining an indication of a second signal measured across the subject, using the indication of the second signal to determine any imbalance and if an imbalance exists, determining a modified first signal in accordance with the imbalance and causing the modified first signal to be applied to the subject to thereby allow at least one impedance measurement to be performed.

Impedance determination

A method of monitoring pulmonary oedema in a subject using a processing system. The method includes, determining a measured impedance value for at least two body segments, at least one of the body segments being a thoracic cavity segment. For each body segment, the measured impedance values are used to determine an index, which is in turn used to determine the presence, absence or degree of pulmonary oedema using the determined indices.

Apparatus for connecting impedance measurement apparatus to an electrode

Sensors for non-invasively determining tissue wetness/hydration based on relative changes in subsurface resistivities in tissue below the sensor when applied to a human body across different frequencies. A sensor including arrays of current-injecting and voltage-sensing electrodes may be placed on a subject's back to determine lung wetness. Sensors may be used as part of a systems and method for determining tissue water content, systems and methods for determining lung wetness, or the like. Sensors for determining relative changes in subsurface resistivities across frequencies and systems include arrays of electrodes used to determine relative changes in subsurface resistivities across frequencies may include pairs of current-injecting and voltage sensing electrodes.

Devices for determining the relative spatial change in subsurface resistivities across frequencies in tissue

A method for performing impedance measurements on a subject. The method includes, in a processing system, causing at least one electrical signal to be applied to the subject via first leads operatively connected to first electrodes provided on the subject, determining a first indication indicative of at least one first electrical signal measured via second leads operatively disconnected from second electrodes positioned on the subject, determining a second indication indicative of at least one second electrical signal measured via second leads operatively connected to second electrodes positioned on the subject, and determining from the indications and the at least one applied signal, at least one instantaneous impedance value.

A method of analysing cardiac functions in a subject using a processing system is described. The method may include applying one or more electrical signals having a plurality of frequencies to the subject and detecting a response to the applied one or more signals from the subject. A characteristic frequency can then be determined from the applied and received signals, and at least one component of the impedance (e.g., reactance, phase shift) can be measured at the characteristic frequency. The impedance or a component of impedance at a characteristic frequency can be determined for a number of sequential time instances. A new characteristic frequency may be determined within a cardiac cycle or the same characteristic frequency may be used throughout the cardiac cycle during which instantaneous values of impedance are determined. These values may be used to determine an indicia of cardiac function.

Cardiac monitoring system

A method of analyzing cardiac functions in a subject using a processing system is described. The method may include applying one or more electrical signals having a plurality of frequencies to the subject and detecting a response to the applied one or more signals from the subject. A characteristic frequency can then be determined from the applied and received signals, and at least one component of the impedance (e.g., reactance, phase shift) can be measured at the characteristic frequency. Thus, the impedance or a component of impedance at a characteristic frequency can be determined for a number of sequential time instances. A new characteristic frequency may be determined within a cardiac cycle (e.g., with each sequential time instant) or the same characteristic frequency may be used throughout the cardiac cycle during which instantaneous values of impedance (or a component of impedance) are determined. These instantaneous values may be used to determine one or more indicia of cardiac function.

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Del Mar, CA, United States of America

Scott Chetham