APPARATUS AND METHOD FOR PROCESSING PHYSIOLOGICAL MEASUREMENT VALUES

• US 20100268041A1
• Filed: 04/09/2010
• Published: 10/21/2010
• Est. Priority Date: 04/15/2009
• Status: Active Grant

• Current Assignee: Biotronik SE & Company KG
• Original Assignee: Biotronik VI Patent AG (Biotronik SE & Company KG)
• Inventors: KRAEMER, Thomas, Paule, Stefan, Lippert, Michael, Czygan, Gerald, Skerl, Olaf
• Granted Patent: US 8,571,641 B2
• Time in Patent Office: Days
• US Class Current: 600/301
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/0537 Measuring body composition by impedance, e.g. tissue hydration or fat content
• CPC Class Codes: A61B 5/1116 Determining posture transitions
• CPC Class Codes: A61B 5/4869 Determining body composition
• CPC Class Codes: A61B 5/4878 Evaluating oedema
• CPC Class Codes: A61B 5/6846 specially adapted to be brought in contact with an internal body part, i.e. invasive
• CPC Class Codes: A61B 5/686 Permanently implanted devices, e.g. pacemakers, other stimulators, biochips A61B5/6861 takes precedence
• CPC Class Codes: A61N 1/36521 the parameter being derived from measurement of an electrical impedance
• CPC Class Codes: A61N 1/36542 controlled by body motion, e.g. acceleration
• CPC Class Codes: A61N 1/3655 controlled by body or blood temperature
• CPC Class Codes: A61N 1/36564 controlled by blood pressure
• CPC Class Codes: A61N 1/36571 controlled by blood flow rate, e.g. blood velocity or cardiac output

Abstract

A monitoring apparatus having a signal input for signals representing measurement values of one or more physiological parameters, and an evaluation and processing unit connected to the signal input. The evaluation and processing unit is designed to select, or differently weight, individual values from the values received for further processing based on one or more criteria such that measurement values raising doubts as to the validity thereof are not selected or given a very low weighting.

Claims

1. A monitoring apparatus comprising:

a signal input for signals that represent measurement values of one or more physiological parameters; and

,

an evaluation and processing unit connected to the signal input, wherein said evaluation and processing unit is configured to

select, or give different weightings to, individual values among the measurement values received and selected, or not selected, for further processing according to one or more criteria such that the measurement values and selected measurement values are given a high weighting or a low weighting, depending on whether previously set or adaptive threshold values for measurement values, and/or previously set or adaptive threshold values for changes compared to or deviations from previously recorded measurement values are adhered to, exceeded, or not met, and

abort an evaluation of the measurement values if a particular measurement value based on weighting will be below a specified or adaptive threshold.

2. The monitoring apparatus according to claim 1, wherein the evaluation and processing unit is further configured to abort a measurement, or completely eliminate the measurement, in an event that, prior to conducting a measurement, it is to be expected from the measurement values of other parameters, or from the parts of a measurement already conducted, that the weighting will be below a certain threshold.

3. The monitoring apparatus according to claim 1, wherein the evaluation and processing unit is further configured to repeat a measurement in an event of an aborted evaluation, or an eliminated measurement, within a specified repetition time frame after a first measurement, as soon as the one or more criteria for elimination of the measurement are no longer met.

4. A monitoring apparatus according to claim 1, wherein the evaluation and processing unit is further configured to select, or give different weightings to, the individual values among the measurement values received for further processing according to one or more criteria such that measurement values that raise doubt as to validity thereof are not selected or given a very low weighting, if:

a variability of a measurement value, which is a mean value from many individual values, exceeds a specified particular threshold value, or

a sensor signal, that identifies an activity of a patient, comprises any one or more of

a Closed Loop Stimulation rate control signal,

accelerometer output value,

respiratory rate, respiration depth,

and/or minute volume,

wherein said sensor signal exceeds the specified particular threshold value, or

a signal, or several signals, indicate an unstable condition of the patient, such as ventricular tachycardia, or

antitachycardiac therapy is being conducted.

5. A monitoring apparatus according to claim 1, wherein the evaluation and processing unit is further configured to select, or give different weightings to, the individual values among the measurement values received for further processing according to one or more criteria such that the measurement values under conditions which enable good comparability are given a high weighting and preferentially evaluated.

6. A monitoring apparatus according to claim 1, wherein the evaluation and processing unit is further configured to give the high weighting to and preferentially evaluate measurement values recorded during a specified time range of the day.

7. The monitoring apparatus according to claim 5, wherein the evaluation and processing unit is further configured to give high weightings to and preferentially evaluate measurement values which are associated with a specified heart rate range, and/or to give the high weightings to and preferentially evaluate measurement values which are associated with a specified mental or physical stress range, and/or give the high weightings to and preferentially evaluate measurement values which accompany a fraction of atrial fibrillation within a certain time period, which is above or below a specified threshold value, and/or give the high weightings to and preferentially evaluate measurement values which accompany a respiratory amplitude and respiratory rate in a predetermined or adaptively determined interval.

8. A monitoring apparatus according to claim 1, wherein the evaluation and processing unit is further configured to select, or give different weightings to, the individual values among the measurement values received for further processing according to one or more criteria such that measurement values obtained under conditions during which a measurement signal exhibits high sensitivity toward an effect to be observed are preferentially evaluated and given a the high weighting.

9. The monitoring apparatus according to claim 8, wherein the evaluation and processing unit is further configured to give high weightings to and preferentially evaluate measurement values which accompany a fraction of atrial fibrillation within a certain time period, which is above a specified threshold, and/or give high weightings to and preferentially evaluate measurement values which are recorded under high physical or mental strain, and/or to give high weightings to and preferentially evaluate measurement values which are recorded within a specified heart rate range.

10. The monitoring apparatus according to claim 8, further comprising an input for a position sensor that indicates a horizontal or vertical position, wherein the evaluation and processing unit is further configured to give high weightings to and preferentially evaluate measurement values recorded in a position that was established beforehand.

11. The monitoring apparatus according to claim 8, further comprising an input for a position sensor signal that indicates a horizontal or vertical position, and another input for a time-of-day-signal wherein the evaluation and processing unit is further configured to give high weightings to and preferentially evaluate measurement values that are recorded during morning, after switching from a horizontal position into a vertical position, or during evening, after switching from a vertical position into a horizontal position.

12. The monitoring apparatus according to claim 1, further comprising:

an impedance capturing unit;

impedance evaluation unit;

wherein the evaluation and processing unit is connected to the impedance capturing unit and impedance evaluation unit;

wherein said impedance capturing unit is configured to determine an impedance signal, which represents an intracardiac impedance curve; and

,

wherein said impedance evaluation unit is further configured to determine an activity signal that indicates high physical strain from a time curve of the impedance signal.

13. A monitoring apparatus according to claim 1, wherein the evaluation and processing unit is further configured to process the measurement values of one or more of the following parameters:

biomarkers, electrolytes, glucose, hematocrit, blood resistivity, temperature and/or outside pressure.

14. The monitoring apparatus according to claim 1, further comprising an impedance capturing unit, wherein the impedance capturing unit and the evaluation and processing unit are integrated in an implant, or the impedance capturing unit is integrated in the implant and the evaluation and processing unit is integrated in an external device that communicates with the implant, or the impedance capturing unit is integrated in the implant and the evaluation and processing unit is integrated in a service center communicating indirectly with the implant.

15. A method for processing measurement values of physiological parameters, wherein individual values among the values received are selected or given different weightings for further processing based on one or more of the following criteria such that measurement values raising doubts as to validity thereof are not selected or given a very low weighting, if:

checking a variability of a measurement value, which is a mean value from many individual values, exceeds a specified particular threshold value, or

checking a sensor signal, that identifies an activity of a patient, which comprises any one or more of

a Closed Loop Stimulation rate control signal,

accelerometer output value,

respiratory rate,

respiration depth,

and/or minute volume,

and determining whether said sensor signal exceeds a specified particular threshold value, or

checking if a signal, or several signals, indicate an unstable condition of a patient, such as ventricular tachycardia, or

checking if antitachycardiac therapy is being conducted.