Abstract: A method for distinguishing between individual human subjects using plethysmographic waveforms. In one embodiment, the method comprises the steps of: receiving a plurality of plethysmographic signals from different individuals; normalizing the signals to the same period length and mean; changing the basis of each of the plurality of signals to obtain its basis vectors and coefficients; reducing the number of coefficients for each signal in the plurality of signals; and calculating the covariance matrix and mean for each individual's set of normalized and dimensionally-reduced plethysmograph waveforms. In another embodiment, the method further comprises the step of taking the Mahalanobis distance between each new plethysmograph waveform that has also been normalized and dimensionally reduced and the stored models of all individuals. In yet another embodiment, the method further comprises the step of finding the index of the stored model with the minimum Mahalanobis distance.

Abstract: The present invention relates to an interface device and a method for communication between a medical device and a computer system. In some embodiments, the interface device comprises a conversion device and/or a processor-transceiver and a memory in electrical communication with the conversion device, wherein the memory contains data to instruct the conversion device and/or the processor transceiver how to communicate with the medical device.

Abstract: A wireless patient monitoring system. In one embodiment the system has a first patient monitoring subsystem including a plurality of sensors and sensor modules; and a processor-transceiver in communication with the plurality of sensors and sensor modules; and a first clinician display subsystem including a processor-transceiver. The processor-transceiver of the first clinician display subsystem broadcasts, on a first predetermined frequency, the frequency the processor-transceiver of the first clinician display subsystem will use to communicate with the processor-transceiver of the first patient monitoring subsystem. The processor-transceiver of the first patient monitoring subsystem then transmits and receives data on the frequency that the processor-transceiver of the first clinician display subsystem will use to communicate with the processor-transceiver of the first patient monitoring subsystem.

Abstract: A magnetic field tolerant amplifier having an amplifier stage, a differential to single-ended output amplifier stage and a first and second delay line. In another embodiment the invention relates to a magnetic gradient cancellation delay line including two coils connected in series at a junction and non-inductively wound to cancel induced currents from magnetic gradient. In another embodiment the invention relates to a patient lead including a flexible circuit substrate having a flexible conductor having distributed impedance. In still yet another embodiment the invention relates to a wireless transceiver system including an RF cancellation delay line; a differential amplifier stage; a differential to single ended output amplifier stage; an A/D converter; an RF transceiver and an antenna.

Abstract: A system and method for triggering an external device in response to an electrocardiogram signal. In one embodiment the method includes determining a peak in the electrocardiogram signal, determining if the electrocardiogram signal is rising or falling at the peak in the signal and triggering a device in response to the rising or falling peak. In one embodiment of the invention an external trigger signal is produced only a rising peak is detected. In one embodiment, the system includes a microprocessor, a peak detector and a trigger circuit. The trigger circuit outputs a trigger signal to an external device when signaled by the peak detector and not inhibited by a signal from the microprocessor.

Abstract: The present invention relates to a system and method for determining the impedance of an electrode at the electrode-body interface. The electrode-body impedance of one of the electrodes may be calculated using the voltage difference between that electrode and a plurality of other electrodes, and the voltage and impedance of an alternating current generator in communication with the electrodes.

Abstract: The present invention relates to an interface device and a method for communication between a medical device and a computer system. In some embodiments, the interface device comprises a conversion device and/or a processor-transceiver and a memory in electrical communication with the conversion device, wherein the memory contains data to instruct the conversion device and/or the processor transceiver how to communicate with the medical device.

Abstract: A magnetic field tolerant amplifier having an amplifier stage, a differential to single-ended output amplifier stage and a first and second delay line. In another embodiment the invention relates to a magnetic gradient cancellation delay line including two coils connected in series at a junction and non-inductively wound to cancel induced currents from magnetic gradient. In another embodiment the invention relates to a patient lead including a flexible circuit substrate having a flexible conductor having distributed impedance. In still yet another embodiment the invention relates to a wireless transceiver system including an RF cancellation delay line; a differential amplifier stage; a differential to single ended output amplifier stage; an A/D converter; an RF transceiver and an antenna.

Abstract: A magnetic field tolerant amplifier having an amplifier stage, a differential to single-ended output amplifier stage and a first and second delay line. In another embodiment the invention relates to a magnetic gradient cancellation delay line including two coils connected in series at a junction and non-inductively wound to cancel induced currents from magnetic gradient. In another embodiment the invention relates to a patient lead including a flexible circuit substrate having a flexible conductor having distributed impedance. In still yet another embodiment the invention relates to a wireless transceiver system including an RF cancellation delay line; a differential amplifier stage; a differential to single ended output amplifier stage; an A/D converter; an RF transceiver and an antenna.

Abstract: A system and method for triggering an external device in response to an electrocardiogram signal. In one embodiment the method includes determining a peak in the electrocardiogram signal, determining if the electrocardiogram signal is rising or falling at the peak in the signal and triggering a device in response to the rising or falling peak. In one embodiment of the invention an external trigger signal is produced only a rising peak is detected. In one embodiment, the system includes a microprocessor, a peak detector and a trigger circuit. The trigger circuit outputs a trigger signal to an external device when signaled by the peak detector and not inhibited by a signal from the microprocessor.

Abstract: A wireless patient monitoring system. In one embodiment the system has a first patient monitoring subsystem including a plurality of sensors and sensor modules; and a processor-transceiver in communication with the plurality of sensors and sensor modules; and a first clinician display subsystem including a processor-transceiver. The processor-transceiver of the first clinician display subsystem broadcasts, on a first predetermined frequency, the frequency the processor-transceiver of the first clinician display subsystem will use to communicate with the processor-transceiver of the first patient monitoring subsystem. The processor-transceiver of the first patient monitoring subsystem then transmits and receives data on the frequency that the processor-transceiver of the first clinician display subsystem will use to communicate with the processor-transceiver of the first patient monitoring subsystem.

Abstract: A magnetic field tolerant amplifier having an amplifier stage, a differential to single-ended output amplifier stage and a first and second delay line. In another embodiment the invention relates to a magnetic gradient cancellation delay line including two coils connected in series at a junction and non-inductively wound to cancel induced currents from magnetic gradient. In another embodiment the invention relates to a patient lead including a flexible circuit substrate having a flexible conductor having distributed impedance. In still yet another embodiment the invention relates to a wireless transceiver system including an RF cancellation delay line; a differential amplifier stage; a differential to single ended output amplifier stage; an A/D converter; an RF transceiver and an antenna.