Method and apparatus for detecting change in intrathoracic electrical impedance
AssigneeMedtronic, Inc.
InventorsRobert W. Stadler, Li Wang
Life of this patent
Estimating the term…
Abstract
A method and apparatus for detection of changes in impedance a patient that includes generating measured impedances, generating an adaptive baseline trend of the measured impedances corresponding to a first time period, generating a short term trend of the measured impedances corresponding to a second time period less than the first time period, and generating a metric of impedance change between the adaptive baseline trend and one of a most recent measured impedance and the short term trend of the measured impedances.
Claims57
An implantable medical device for detection of changes in impedance in a patient, comprising:
- means for generating measured impedances;
- means for generating an adaptive baseline trend of the measured impedances corresponding to a first time period;
- means for generating a short term trend of the measured impedances corresponding to a second time period less than the first time period;
- and
- means for generating a metric of impedance change between the adaptive baseline trend and one of a most recent measured impedance and the short term trend of the measured impedances.
A method for detection of changes in impedance a patient, comprising:
- generating measured impedances;
- generating an adaptive baseline trend of the measured impedances corresponding to a first time period;
- generating a short term trend of the measured impedances corresponding to a second time period less than the first time period;
- and
- generating a metric of impedance change between the adaptive baseline trend and one of a most recent measured impedance and the short term trend of the measured impedances.
An implantable medical device, comprising:
- a plurality of electrodes;
- an output circuit outputting a plurality of output pulse signals along a vector formed by electrodes of the plurality of electrodes;
- a measurement circuit generating a corresponding plurality of measurement signals in response to the plurality of output pulse signals;
- and
- a microprocessor determining a plurality of period average impedances in response to the plurality of output pulse signals and the plurality of measurement signals corresponding to a predetermined time period, and generating an adaptive baseline trend of period average impedances of the plurality of period average impedances corresponding to a first time period and a short term trend of period average impedances of the plurality of period average impedances corresponding to a second time period less than the first time period, the microprocessor generating a metric of impedance change between the baseline trend and one of a most recent period average impedance and the short term trend.
A computer readable medium having computer executable instructions for performing a method comprising:
- generating measured impedances;
- generating an adaptive baseline trend of the measured impedances corresponding to a first time period;
- generating a short term trend of the measured impedances corresponding to a second time period less than the first time period;
- and
- generating a metric of impedance change between the adaptive baseline trend and one of a most recent measured impedance and the short term trend of the measured impedances.
Dependencies are inferred from the claim text.