PROBABILISTIC PARAMETER ESTIMATION USING FUSED DATA APPARATUS AND METHOD OF USE THEREOF

• US 20120022844A1
• Filed: 07/12/2011
• Published: 01/26/2012
• Est. Priority Date: 04/22/2009
• Status: Active Grant

• Current Assignee: Vital Metrix Inc.
• Original Assignee: Streamline Automation LLC
• Inventors: Teixeira, Rodrigo
• Granted Patent: US 9,451,886 B2
• Time in Patent Office: Days
• US Class Current: 703/11
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/7203 for noise prevention, reduction or removal
• CPC Class Codes: A61B 5/7214 using signal cancellation, e.g. based on input of two identical physiological sensors spaced apart, or based on two signals derived from the same sensor, for different optical wavelengths
• CPC Class Codes: G06F 18/251 of input or preprocessed data
• CPC Class Codes: G06F 2218/00 Aspects of pattern recognition specially adapted for signal processing
• CPC Class Codes: G16H 40/63 for local operation
• CPC Class Codes: G16H 50/50 for simulation or modelling of medical disorders

Abstract

A probabilistic digital signal processor using data from multiple instruments is described. In one example, an analyzer is configured to: receive discrete first and second input data, related to a first and second sub-system of the system, from a first and second instrument, respectively. A system processor is used to fuse the first and second input data into fused data. The system processor optionally includes: (1) a probabilistic processor configured to convert the fused data into at least two probability distribution functions and (2) a dynamic state-space model, the dynamic state-space model including at least one probabilistic model configured to operate on the at least two probability distribution functions. The system processor iteratively circulates the at least two probability distribution functions in the dynamic state-space model in synchronization with receipt of updated input data, processes the probability distribution functions, and generates an output related to the state of the system.

Claims

1. An apparatus for estimation of state of a system, comprising:

an analyzer configured to;

receive discrete first input data, related to a first sub-system of the system, from a first instrument; and

receive discrete second input data, related to a second sub-system of the system, from a second instrument,

said analyzer comprising;

a system processor configured to fuse the first input data and the second input data into fused data, said system processor comprising;

a probabilistic processor configured to convert the fused data into at least two probability distribution functions; and

a dynamic state-space model, said dynamic state-space model comprising at least one probabilistic model configured to operate on said at least two probability distribution functions,

wherein said system processor iteratively circulates said at least two probability distribution functions in said dynamic state-space model in synchronization with receipt of at least one of;

updated first input data; and

updated second input data,

said system processor configured to process the probability distribution functions to generate an output related to the state of the system.

2. The apparatus of claim 1, further comprising:

integration into said analyzer at least one of said first instrument and said second instrument.

3. The apparatus of claim 1, wherein said output comprises at least one of:

a discrete monitored parameter value; and

a discrete estimated parameter value.

4. The apparatus of claim 1, wherein said output comprises an output probability distribution function.

5. The apparatus of claim 1, said dynamic state-space model comprising:

a first process model configured to model physical aspects of the first sub-system;

a probabilistic process model configured to model physical aspects of the second sub-system; and

an observation model configured to model at least one data noise source related to the fused data.

6. The apparatus of claim 1, said dynamic state-space model comprising:

a fused process model configured to model aspects of both the first sub-system and the second sub-system; and

a probabilistic observation model configured to detect motion related artifacts of at least one sensor used to generated the first input data.

7. The apparatus of claim 1, wherein said system comprises any of:

a mechanical system; and

a medical system.

8. The apparatus of claim 1, wherein said probabilistic model comprises a probabilistic physiological model of an organ of a body.

9. The apparatus of claim 1, wherein said probabilistic model comprises a model of at least one of:

a hemodynamic system of a body; and

an electrodynamic system of a body, wherein the electrodynamic system comprises a system wherein the body generates an electrical signal in the absence of a sample probe.

10. The apparatus of claim 1, wherein said first instrument comprises at least one of:

a Doppler system;

an electrocardiogram device;

an electroencephalogram device;

a pulse oximeter;

a photoplethysmographic device; and

an ultrasound device.

11. The apparatus of claim 1, wherein said second instrument comprises at least one of:

a Doppler system;

an electrocardiogram device;

an electroencephalogram device;

a pulse oximeter;

a photoplethysmographic device;

an ultrasound device;

a carbon dioxide meter;

a heart catheter;

an impedance cardiography device;

a mixed venous oxygen saturation catheter;

a transcutaneous blood gas sensing meter; and

a pressure cuff yielding a pressure waveform.

12. The apparatus of claim 1, said analyzer further configured to receive discrete third input data, related to a local environment outside of the system, from a third instrument, wherein said fused data incorporates the third input data.

13. The apparatus of claim 12, wherein the third input data comprises at least one of:

temperature;

pressure;

vibration; and

humidity.

14. The apparatus of claim 1, said analyzer further configured to receive accelerometer data, said probabilistic processor configured to use the accelerometer data for outlier determination in the fused data.

15. A method for estimating state of a system, comprising the steps of:

an analyzer receiving;

discrete first input data, related to a first sub-system of the system, from a first instrument; and

discrete second input data, related to a second sub-system of the system, from a second instrument,

a system processor of said analyzer fusing the first input data and the second input data into fused data;

a probabilistic processor, of said system processor, converting the fused data into at least two probability distribution functions; and

a dynamic state-space model, operating in said system processor, operating on said at least two probability distribution functions with at least one physics based probabilistic model;

said system processor iteratively circulating said probability distribution functions in said dynamic state-space model in synchronization with receipt of at least one of;

updated first input data; and

updated second input data; and

said system processor processing the probability distribution functions to generate an output related to the state of the system.

16. The method of claim 15, wherein said first instrument comprises a first medical device configured to measure a first parameter having a first unit of measure, wherein said second instrument comprises a second medical device configured to measure a second parameter having a second unit of measure, said first unit of measure distinct from said second unit of measure.

17. The method of claim 16, further comprising a step of:

using said probabilistic model to generate a third parameter having a third unit of measure, said third unit of measure distinct from both said first unit of measure and said second unit of measure.

18. The method of claim 15, wherein said output comprises a probability distribution function representative of a medical state.

19. The method of claim 15, wherein said first instrument comprises a pulse oximeter, wherein said second instrument comprises an electrocardiogram device.

20. The method of claim 19, further comprising the step of:

generating a medical metric using said pulse oximeter and said electrocardiogram device, said output comprising said medical metric, said medical metric comprising at least one of;

an arrhythmia prediction;

a heart stroke volume measure; and

a measure of permittivity.