Abstract
Autonomic reflexes are responsible for adjusting the cardiovascular system in response to gravitational displacement of blood during changes in posture1. In human physiology, a posture change from supine to standing results in venous pooling in the lower limbs and pelvic area (equivalent to the loss of 500m1 of blood from the systemic circulation) and an increased filtration from capillaries into interstitial space2. In turn, these effects cause a transient dip in effective circulating blood volume and potentially a small reduction in cerebral and peripheral oxygen delivery. This effect is not prolonged in a healthy individual since the decrease in arterial pressure triggers an immediate response from the baroreceptor-mediated sympathetic mechanisms.
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References
A. Vander, J. Sherman, D. Luciano, Human Physiology: The mechanisms of body function ( WCB McGraw-Hill, International Ed, 1998 ).
M. Lye, T. Walley, Haemodynamic responses in young and elderly healthy subjects during ambient and warm head-up tilt, Clinical Science, 94, 493–498 (1998).
C. E. Elwell, R. Springett, E. Hillman, D. T. Delpy, Oscillations in cerebral haemodynamics–implications for functional activation studies, Adv. Exp. Med. & Biol., 471, 57–65 (1999).
H. Obrig, M. Neufang, R. Wenzel, M. Kohl, J. Steinbrink, K. Einhaupl, A. Viliringer, Spontaneous low frequency oscillations of cerebral haemodynamics and metabolism in human adults, Neurolmage, 12, 623–639 (2000).
S. J. Matcher, P. Kirkpatrick, K. Nahid, M. Cope, D.T. Delpy Absolute quantification methods in tissue near-infrared spectroscopy. Proc SPIE 2389, 486–95
A. Duncan, J. H. Meek, M. Clemence, L. Tyszczuk, M. Cope, and D. T. Delpy, Optical pathlength measurements on the adult head, calf and forearm and the head of the newborn infant using phase resolved optical spectroscopy, Phys. Med. Biol., 40, 295–304 (1995).
Task force of the European society of Cardiology and the North American Society of Pacing and Electrophysiology, Heart rate variability: standards of measurement, physiological interpretation and clinical use. European Heart Journal, 17, 354–381 (1994).
G. Preiss, C. Polosa, Patterns of sympathetic neuron activity associated with Mayer waves. Am J Physiol, 226 (3), 724–730 (1974)
T. B. J. Kuo, C. M. Chern, W. Y. Sheng, W. J. Wong, H. H. Hu, Frequency domain analysis of cerebral blood flow velocity and its correlation with arterial blood pressure. J Cereb Blood Flow Metab 18, 311–318 (1998)
T. Muller, M. Reinhard, E. Oehm, A. Hetzel, J. Timmer, Detection of very low-frequency oscillations of cerebral haemodynamics is influenced by data detrending. Med Biol Eng Comput, 41, 69–74 (2003)
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Tachtsidis, I., Elwell, C.E., Lee, CW., Leung, T.S., Smith, M., Delpy, D.T. (2003). Spectral Characteristics of Spontaneous Oscillations in Cerebral Haemodynamics are Posture Dependent. In: Thorniley, M., Harrison, D.K., James, P.E. (eds) Oxygen Transport to Tissue XXV. Advances in Experimental Medicine and Biology, vol 540. Springer, Boston, MA. https://doi.org/10.1007/978-1-4757-6125-2_6
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DOI: https://doi.org/10.1007/978-1-4757-6125-2_6
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