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bpshape wk4: a computer program that implements a physiological model for analyzing the shape of blood pressure waveformsWe describe the theory and computer implementation of a newly-derived mathematical model for analyzing the shape of blood pressure waveforms. Input to the program consists of an ECG signal, plus a single continuous channel of peripheral blood pressure, which is often obtained invasively from an indwelling catheter during intensive-care monitoring or non-invasively from a tonometer. Output from the program includes a set of parameter estimates, made for every heart beat. Parameters of the model can be interpreted in terms of the capacitance of large arteries, the capacitance of peripheral arteries, the inertance of blood flow, the peripheral resistance, and arterial pressure due to basal vascular tone. Aortic flow due to contraction of the left ventricle is represented by a forcing function in the form of a descending ramp, the area under which represents the stroke volume. Differential equations describing the model are solved by the method of Laplace transforms, permitting rapid parameter estimation by the Levenberg-Marquardt algorithm. Parameter estimates and their confidence intervals are given in six examples, which are chosen to represent a variety of pressure waveforms that are observed during intensive-care monitoring. The examples demonstrate that some of the parameters may fluctuate markedly from beat to beat. Our program will find application in projects that are intended to correlate the details of the blood pressure waveform with other physiological variables, pathological conditions, and the effects of interventions.
Document ID
20050000497
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Ocasio, W. C.
(Harvard-M.I.T. Division of Health Sciences and Technology Boston, MA)
Rigney, D. R.
Clark, K. P.
Mark, R. G.
Goldberger, A. L.
Date Acquired
August 22, 2013
Publication Date
April 1, 1993
Publication Information
Publication: Computer methods and programs in biomedicine
Volume: 39
Issue: 4-Mar
ISSN: 0169-2607
Subject Category
Life Sciences (General)
Funding Number(s)
CONTRACT_GRANT: 1-P30-AG-08812-01
CONTRACT_GRANT: 1-RO1-HL-42171
CONTRACT_GRANT: DA06306
Distribution Limits
Public
Copyright
Other
Keywords
Non-NASA Center
NASA Discipline Cardiopulmonary

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