Comparison of Baroreflex Sensitivity Estimators using Spontaneous and Controlled Breathing
نویسندگان
چکیده
Baroreflex sensitivity (BRS) reflects the parallel fluctuations of arterial pressure and heart rate, determining the function of the arterial baroreflex. In this study the ECG and blood pressure were collected from healthy adult males (n=12) using spontaneous and controlled breathing at 0.25Hz. The BRS was analysed using sequence method, alpha coefficient and transfer function technique. The objective was to compare the BRS estimates obtained with different measurement arrangements and study the correlations between BRS methods. Our results showed that the BRS estimates using controlled breathing differed from the BRS obtained with spontaneous breathing. Spectral BRS techniques produced quite similar and strongly correlating BRS estimates within low frequency (LF, 0.04-0.15Hz) and high frequency (HF, 0.15-0.4Hz) bands. The sequence method differs significantly from other techniques. Correlations between the estimators within the same measurement arrangements were high.
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