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Dysfunction of the autonomic nervous system is a frequent finding in many neurological and internal diseases. The quantitative assessment of cardiovascular and sudomotor function is important for diagnosing the autonomic impairment. In this review article, we focus on standard tests that allow evaluation of cardiovascular and sudomotor autonomic functions and describe methods of quantitative assessment that are better suited for research.

Background: In diabetic patients, impairment of the cardiovagal limb of the baroreflex has been well established. However, the role of sympathetic mediated baroreflex vasomotor control of the blood vessels is not well defined. We therefore assessed the vasomotor responses to sinusoidal baroreceptor stimulation in diabetic patients., Materials and Methods: We studied 14 type II diabetic patients (age; 57 +/- 7 years) and 18 healthy controls (age; 59 +/- 11 years). Oscillatory neck suction was applied at 0.1 Hz to assess the sympathetic modulation of the heart and blood vessels, and at 0.2 Hz to assess the effect of parasympathetic stimulation on the heart. Breathing was paced at 0.25 Hz. Spectral analysis was used to evaluate the oscillatory responses of RR-interval and blood pressure., Results: The diabetic patients showed a significantly lower RR-interval response (P < 0.05) to the 0.1 Hz neck suction (2.52 +/- 0.50-3.62 +/- 0.54 ln ms2) than the controls (4.23 +/- 0.31-6.74 +/- 0.36 ln ms2). The increase in power of 0.1 Hz systolic blood pressure oscillations during 0.1 Hz suction was also significantly smaller (P < 0.05) in the diabetics (1.17 +/- 0.44-1.69 +/- 0.44 mmHg2) than in the controls (1.60 +/- 0.29 mmHg2-5.87 +/- 1.25 mmHg2). The magnitude of the peak of the 0.2 Hz oscillation in the RR-interval in response to 0.2 Hz neck stimulation was significantly greater (P < 0.05) in the controls (3.42 +/- 0.46 ln ms2) than in the diabetics (1.58 +/- 0.44 ln ms2)., Conclusion: In addition to cardiovagal dysfunction, baroreflex-mediated sympathetic modulation of the blood vessels is impaired in type II diabetic patients.

Diabetic autonomic neuropathy is the most frequent autonomic neuropathy in western countries. Diabetic autonomic neuropathy affects almost every organ. Among the most common symptoms are cardiovascular disturbances such as reduced heart rate variability and pathologic orthostatic reaction. The diagnosis of diabetic autonomic neuropathy is mainly based on the analysis of cardiovascular challenge maneuvers. The following article describes epidemiology, clinical findings, diagnosis, pathogenesis, therapeutic options and prognosis in diabetic autonomic neuropathy.

This review article focuses on the functional anatomy of the central autonomic nervous system and the autonomic symptoms and dysfunctions occurring with epileptogenic activity involving areas of the central autonomic nervous system. Clinical experiences have demonstrated a close relation between epileptic and central autonomic activity. Autonomic symptoms are frequent signs of epileptic seizures and may cause dysfunctions in almost every organ system. Cardiorespiratory dysfunction has been described interictually. The increased frequency of sudden unexplained death in epilepsy patients may be related to disturbances in cardiac autonomic control. In contrast, electrical vagal stimulation reduces epileptogenic activity by influencing the central autonomic nervous system.

Background: Many polyneuropathies manifest autonomic disturbances. Diabetic neuropathy, the most frequent neuropathy in the western world, serves as model of the symptomatology of autonomic disturbances., Diabetic Neuropathy: Clinical symptoms comprise pupillary and cardiovascular dysfunction such as orthostatic hypotonia and syncopes, thermoregulatory, gastrointestinal symptoms, disturbances in urogenital and respiratory function and unawareness of hypoglycemia., Other Neuropathies: This article also describes autonomic symptoms in alcoholic neuropathy, in Guillain-Barré syndrome, in paraneoplastic polyneuropathies, in toxic neuropathies, in acute and subacute autonomic neuropathy, in amyloidosis, in porphyria, in familiar dysautonomia, in HIV infection and in botulism.