[Assessment of the functioning of autonomic nervous system in the context of cardiorespiratory reflex control]

Derangements within autonomic nervous system take part in the natural history of cardiovascular disease. Current paper presents three categories of methods measuring autonomic status: direct methods (e.g. laboratory tests measuring circulating catecholamine levels or based on isotopes, microneurography), indirect methods applied at rest (e.g. analysis of heart rate variability, spectral and sequence methods of arterial baroreflex sensitivity assessment) and indirect methods, associated with the exposure to physiological stimuli (e.g. Ewing's battery, central and peripheral chemoreceptor sensitivity assessment, invasive methods of arterial baroreflex sensitivity assessment). This review provides an insight into the physiology of reflex regulatory mechanisms within cardiorespiratory system, including their complex and unstable nature.