الفهرس | Only 14 pages are availabe for public view |
Abstract The autonomic nervous system enables the body to adjust its circulation and respiration to maintain an appropriate oxygen delivery to the tissues. It is therefore, necessary to continuously restore the very sensitive symmetry between the two efferent- limbs of the autonomic nervous system - the sympathetic and the parasympathetic. Acute or chronic disturbances of this sympathetic / parasympathetic balance contribute to the pathogenesis of the cardinal symptoms of various disease states; e.g., to the dyspnea and exercise intolerance in chronic heart failure or to tachycardia, hypertension and hyperventilation during acute hypoxia in bronchial asthma. The physiological interplay of cardiovascular and ventilatory mechanisms in regulating oxygen delivery to the tissues is well known and described, but our knowledge. of the cardiorespiratory reflex behavior in disease states is limited. Though disorders, requiring treatment on the intensive care unit (lCU), are accompanied by disturbances of the sympathetic/vagal balance, there are only a few studies describing the autonomic tone and the interference of the cardiorespiratory reflexes in ICU patients. Assessment of impaired autonomic nervous system function could not only be helpful in explaining the pathogenic origin of these disorders; it provides the ICU physician with a potent tool for evaluation of disease prognoses, for the introduction of new therapeutic strategies and for the differentiation between chronic adaptive processes of the nervous system, such as occur in chronic heart failure patients, or acute processes, such as in hypovolemic shock. |