Surgery – Diagnostic testing – Cardiovascular
Patent
1998-08-20
2000-07-04
Nasser, Robert L.
Surgery
Diagnostic testing
Cardiovascular
600485, 600300, A61B 500
Patent
active
060831723
ABSTRACT:
A method and apparatus for reducing the effects of noise on a system for measuring physiological parameters, such as, for example, a pulse oximeter. The method and apparatus of the invention take into account the physical limitations on various physiological parameters being monitored when weighting and averaging a series of measurements. Varying weights are assigned different measurements, measurements are rejected, and the averaging period is adjusted according to the reliability of the measurements. Similarly, calculated values derived from analyzing the measurements are also assigned varying weights and averaged over adjustable periods. More specifically, a general class of filters such as, for example, Kalman filters, is employed in processing the measurements and calculated values. The filters use mathematical models which describe how the physiological parameters change in time, and how these parameters relate to measurement in a noisy environment. The filters adaptively modify a set of averaging weights to optimally estimate the physiological parameters.
REFERENCES:
patent: 4549551 (1985-10-01), Dyck et al.
patent: 4705049 (1987-11-01), John
patent: 4763282 (1988-08-01), Rosenberg
patent: 4800495 (1989-01-01), Smith
patent: 4802486 (1989-02-01), Goodman et al.
patent: 4949710 (1990-08-01), Dorsett et al.
patent: 4958638 (1990-09-01), Sharpe et al.
patent: 5025791 (1991-06-01), Niwa
patent: 5078136 (1992-01-01), Stone et al.
patent: 5479922 (1996-01-01), Reichl
patent: 5482036 (1996-01-01), Diab et al.
patent: 5490505 (1996-02-01), Diab et al.
patent: 5511042 (1996-04-01), O'Brien, Jr.
patent: 5632272 (1997-05-01), Diab et al.
patent: 5685299 (1997-11-01), Diab et al.
patent: 5769785 (1998-06-01), Diab et al.
Nehorai, A., "A Minimal Parameter Adaptive Notch Filter With Constrained Poles and Zeros," IEEE Transactions on Acoustics Speech, and Signal Processing, ASSP-33 (4): 983-996 (1985).
Nehorai, A., et al., "Adaptive Comb Filtering For Harmonic Signa Enhancement," IEEE Transactions on Acoustics, Speech, and signal Processing, ASSP-14 (5):1124-1138 (1986).
IEEE Transactions on Signal Processing, 41 (4):1677-1680 (1993).
Gilbert Strang, Introduction to Applied Mathematics, Wellesley Cambridge Press, Wellesley, Mass. (1986), pp. 148-152.
Robert Grover Brown and Patrick Y.C. Hwang, Introduction to Random Signals and Applied Kalman Filtering (2.sub.nd Ed.), John Wiley & Sons, Inc., New York (1992), pp. 231-232, 261.
Baker, Jr. Clark R.
Yorkey Thomas J.
Nasser Robert L.
Nellcor Puritan Bennett Incorporated
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