Assessment of Baroreflex Control of Heart Rate During General Anesthesia Using a Point Process Method.

Neuroscience Statistics Research Lab, Massachusetts General Hospital, Harvard Medical School / Harvard-MIT Division of Health Science and Technology, Boston, MA, USA.
Acoustics, Speech, and Signal Processing, 1988. ICASSP-88., 1988 International Conference on (Impact Factor: 4.63). 05/2009; 2009:333-336. DOI: 10.1109/ICASSP.2009.4959588
Source: DBLP

ABSTRACT Evaluation of baroreflex control of heart rate (HR) has important implications in clinical practice of anesthesia and postoperative care. In this paper, we present a point process method to assess the dynamic baroreflex gain using a closed-loop model of the cardiovascular system. Specifically, the inverse Gaussian probability distribution is used to model the heartbeat interval, whereas the instantaneous mean is identified by a linear or bilinear bivariate regression on the previous R-R intervals and blood pressure (BP) measures. The instantaneous baroreflex gain is estimated in the feedback loop with a point process filter, while the RR→BP feedforward frequency response is estimated by a Kalman filter. In addition, the instantaneous cross-spectrum and cross-bispectrum (as well as their ratio) can also be estimated. All statistical indices provide a valuable quantitative assessment of the interaction between heartbeat dynamics and hemodynamics during general anesthesia.

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