利用Volterra-Wiener模型估算壓力反射敏感度－以EUROBAVAR資料庫為例

Evaluation of baroreflex sensitivity by Volterra-Wiener model - A study on EUROBAVAR dataset

巫垂洲(Tsui-Chou Wu) ； 高材(Tsair Kao)

《弘光學報》 60期 (2010/09) Pp. 74-86

https://doi.org/10.6615/HAR.201009.60.07

摘要

人體血壓的短期調控機制可透過感壓反射之回授而加以調節，壓力反射敏感度(BRS)為此調節之狀態指標。目前使用的非侵入式之“自發BRS分析法＂大多採線性系統模型，並選定開迴路或閉迴路架構來進行時域或頻域之分析計算。然人體血壓複雜的生理調控機制實為一非線性動態系統，故尋得一合適之非線性動態分析模型，應能提供更為準確及較少偏差的BRS值估計。本論文採用非線性Volterra-Wiener之數學模型，配合正交Laguerre基底函數，對動脈血壓之收縮壓變動(ΔSBP)及心跳間期變動(ΔRRI)進行分析。實際應用此方法對EUROBAVAR資料庫數據樣本進行分析，並將結果與alpha係數法與序列法所估得之BRS值，進行比對分析。本論文提出之方法所估算的BRS值，在平躺與站立姿勢下，皆較alpha係數法與序列法所得數值低，而平躺/站立比(Lying/Standing ratio)則高於上述兩方法。本方法改善了“自發BRS分析法＂數值高估的情況。此外針對EUROBAVAR資料庫數據所有的樣本，皆能估得BRS值。

關鍵字

壓力反射敏感度 ； 自發BRS分析法 ； Volterra模型 ； EUROBAVAR資料庫

並列摘要

The short-term control of blood pressure is the arterial baroreflex and the baroreflex sensitivity (BRS) is the indicator that describes such mechanism. The BRS estimation, spontaneous BRS index, is based on beat-to-beat time series analysis of systolic blood pressure and heart rate interval underlying openloop or closed-loop linear model in time or frequency domain. However, the physiological regulatory mechanism of blood pressure is inherently nonlinear and dynamic. It would make a great improvement for accurate assessment of arterial baroreflex by a suitable dynamic nonlinear model. This paper presents a nonlinear Volterra-Wiener model and the Laguerre expansion technique to analyze the changes in systolic arterial blood pressure, as model’s input, and their corresponding changes in heart rate interval, as model ’s output. Compared with the measurements by sequence technique and alpha coefficient technique in EUROBAVAR dataset, we found that the estimates of BRS by the proposed technique were lower either in lying or in standing position and the lying/standing ratio were higher. The proposed technique improves the overestimation of spontaneous BRS index obtained by other approaches such as sequence technique or alpha coefficient technique.

並列關鍵字

Baroreflex sensitivity ； Spontaneous BRS index ； Volterra-Wiener model ； EUROBAVAR

參考文獻

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