Cambios dinámicos de la sensibilidad del barorreceptor al ponerse de pie.

INTRODUCTION: The baroreceptor(BR) is very important in the control of the peripheral circulation and blood pressure (BP) which are regulated in diverse circumstances. We studied the baroreceptor regulation during the change from supine to upright position as this is the most important function of the baroreceptor reflex. OBJECTIVE: Recording and measure the baroreflex sensitivity (BRS) in recumbent and standing positions. METHODS: We used the Finometer®, a non-invasive beat-to-beat method, to record and to measure BP, heart rate, total peripheral resistance, R-R interval and the BRS. We obtained the BRS by dividing the R-R interval (ms) to systolic blood pressure (mmHg) of the previous beat. We evaluated 15 healthy subjects who fulfilled the inclusion criteria. All subjects were studied at rest in recumbent position during 20 min and 5 min in standing position. Graphics and time series of all hemodynamic parameters were obtained in both recumbent and upright positions. RESULTS: We investigated 11 men and 4 women aged between 21 and 39 years old (28.73 ± 5.2). BRS had values from 9.18 to 9.42 ms/mmHg (9.3 ± 0.8) in recumbent position, while in standing up position the values were from 7.57 to 7.75 ms/mmHg (7.66 ± 0.62) (p = 0.01). CONCLUSIONS: BRS had lower values in upright than in recumbent position. [ABSTRACT FROM AUTHOR]