TY - JOUR
T1 - Effect of paced breathing on ventilatory and cardiovascular variability parameters during short-term investigations of autonomic function
AU - Pinna, G. D.
AU - Maestri, R.
AU - La Rovere, M. T.
AU - Gobbi, E.
AU - Fanfulla, F.
PY - 2006/1
Y1 - 2006/1
N2 - Paced breathing (PB) around 0.25 Hz has been advocated as a means to avoid confounding and to standardize measurements in short-term investigations of autonomic cardiovascular regulation. Controversy remains, however, as to whether it causes any alteration in autonomic control. We addressed this issue in 40 supine, middle-aged, healthy volunteers by assessing the changes induced by PB (0.25 Hz for 8 min) on 1) ventilatory parameters, 2) the indexes of autonomic control of cardiovascular function, and 3) the spectral indexes of cardiovascular variability. Subjects were grouped into group 1 (n = 31), if spontaneous breathing was regular and within the high-frequency (HF) band (0.15- 0.45 Hz), or group 2 (n = 9), if it was irregular or slow (2 decreased by [median (lower quartile, upper quartile)] -0.2 (-0.5, -0.1)% (group 1, P <0.0001) and -0.6 (-0.8, -0.5)% (group 2, P = 0.008). Mean R-R interval and systolic and diastolic pressure remained remarkably stable (all P ≥ 0.13, both groups). No significant changes were observed in spectral indexes of R-R and pressure variability (all P ≥ 0.12, measured only in group 1 to avoid confounding), except in the HF power of pressure signals, which significantly increased (all P <0.05) in association with increased tidal volume. In conclusion, PB at 0.25 Hz causes a slight hyperventilation and does not affect traditional indexes of autonomic control or, in subjects with spontaneous breathing in the HF band, most relevant spectral indexes of cardiovascular variability. These findings support the notion that PB does not alter cardiovascular autonomic regulation compared with spontaneous breathing.
AB - Paced breathing (PB) around 0.25 Hz has been advocated as a means to avoid confounding and to standardize measurements in short-term investigations of autonomic cardiovascular regulation. Controversy remains, however, as to whether it causes any alteration in autonomic control. We addressed this issue in 40 supine, middle-aged, healthy volunteers by assessing the changes induced by PB (0.25 Hz for 8 min) on 1) ventilatory parameters, 2) the indexes of autonomic control of cardiovascular function, and 3) the spectral indexes of cardiovascular variability. Subjects were grouped into group 1 (n = 31), if spontaneous breathing was regular and within the high-frequency (HF) band (0.15- 0.45 Hz), or group 2 (n = 9), if it was irregular or slow (2 decreased by [median (lower quartile, upper quartile)] -0.2 (-0.5, -0.1)% (group 1, P <0.0001) and -0.6 (-0.8, -0.5)% (group 2, P = 0.008). Mean R-R interval and systolic and diastolic pressure remained remarkably stable (all P ≥ 0.13, both groups). No significant changes were observed in spectral indexes of R-R and pressure variability (all P ≥ 0.12, measured only in group 1 to avoid confounding), except in the HF power of pressure signals, which significantly increased (all P <0.05) in association with increased tidal volume. In conclusion, PB at 0.25 Hz causes a slight hyperventilation and does not affect traditional indexes of autonomic control or, in subjects with spontaneous breathing in the HF band, most relevant spectral indexes of cardiovascular variability. These findings support the notion that PB does not alter cardiovascular autonomic regulation compared with spontaneous breathing.
KW - Baroreflex sensitivity
KW - Controlled breathing
KW - Heart rate variability
KW - Spectral analysis
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U2 - 10.1152/ajpheart.00438.2005
DO - 10.1152/ajpheart.00438.2005
M3 - Article
C2 - 16155106
AN - SCOPUS:33644804846
VL - 290
JO - American Journal of Physiology
JF - American Journal of Physiology
SN - 0363-6119
IS - 1
ER -