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Handbook of Clinical Neurology 2019The autonomic nervous system has widespread innervation to nearly every organ system in the body. In order to understand the basics of autonomic function, knowledge of... (Review)
Review
The autonomic nervous system has widespread innervation to nearly every organ system in the body. In order to understand the basics of autonomic function, knowledge of the neuroanatomy of the autonomic nervous system is necessary. Frequently considered to control the "fight or flight" and "rest and digest" functions, the autonomic nervous system has an intricate network of connections to finely tune the systemic response to nearly any situation. Although traditionally considered two discrete systems (sympathetic and parasympathetic), the enteric nervous system is now considered a third component of the autonomic nervous system. This chapter reviews the background of the neuroanatomical distribution of the autonomic nervous system in order to facilitate understanding the basics of autonomic function.
Topics: Animals; Autonomic Nervous System; Autonomic Nervous System Diseases; Brain; Enteric Nervous System; Heart Rate; Humans; Spinal Cord
PubMed: 31277865
DOI: 10.1016/B978-0-444-64032-1.00027-8 -
Journal of the American College of... Mar 2019Autonomic nervous system control of the heart is a dynamic process in both health and disease. A multilevel neural network is responsible for control of chronotropy,... (Review)
Review
Autonomic nervous system control of the heart is a dynamic process in both health and disease. A multilevel neural network is responsible for control of chronotropy, lusitropy, dromotropy, and inotropy. Intrinsic autonomic dysfunction arises from diseases that directly affect the autonomic nerves, such as diabetes mellitus and the syndromes of primary autonomic failure. Extrinsic autonomic dysfunction reflects the changes in autonomic function that are secondarily induced by cardiac or other disease. An array of tests interrogate various aspects of cardiac autonomic control in either resting conditions or with physiological perturbations from resting conditions. The prognostic significance of these assessments have been well established. Clinical usefulness has not been established, and the precise mechanistic link to mortality is less well established. Further efforts are required to develop optimal approaches to delineate cardiac autonomic dysfunction and its adverse effects to develop tools that can be used to guide clinical decision-making.
Topics: Autonomic Nervous System; Autonomic Nervous System Diseases; Heart; Heart Diseases; Heart Rate; Humans; Myocardial Contraction
PubMed: 30871703
DOI: 10.1016/j.jacc.2018.12.064 -
Continuum (Minneapolis, Minn.) Feb 2020This article provides a summary of the autonomic neuropathies, including neuropathies associated with diabetes mellitus, neuropathies due to amyloid deposition,... (Review)
Review
PURPOSE OF REVIEW
This article provides a summary of the autonomic neuropathies, including neuropathies associated with diabetes mellitus, neuropathies due to amyloid deposition, immune-mediated autonomic neuropathies (including those associated with a paraneoplastic syndrome), inherited autonomic neuropathies, and toxic autonomic neuropathies. The presenting features, diagnostic investigations, and natural history of these neuropathies are discussed.
RECENT FINDINGS
Recent findings in autonomic peripheral neuropathy include data on the epidemiology and atypical presentations of diabetic autonomic neuropathy, treatment-induced neuropathy of diabetes mellitus, the presentation of immune-mediated neuropathies, and advances in hereditary neuropathy associated with amyloidosis and other hereditary neuropathies.
SUMMARY
Knowledge and recognition of the clinical features of the autonomic neuropathies, combined with appropriate laboratory and electrophysiologic testing, will facilitate accurate diagnosis and management.
Topics: Autonomic Nervous System; Autonomic Nervous System Diseases; Diabetic Neuropathies; Disease Progression; Genetic Diseases, Inborn; Humans; Peripheral Nervous System Diseases
PubMed: 31996622
DOI: 10.1212/CON.0000000000000825 -
The Lancet. Neurology Sep 2017A substantial minority of patients who survive an acquired brain injury develop a state of sympathetic hyperactivity that can persist for weeks or months, consisting of... (Review)
Review
A substantial minority of patients who survive an acquired brain injury develop a state of sympathetic hyperactivity that can persist for weeks or months, consisting of periodic episodes of increased heart rate and blood pressure, sweating, hyperthermia, and motor posturing, often in response to external stimuli. The unifying term for the syndrome-paroxysmal sympathetic hyperactivity (PSH)-and clear diagnostic criteria defined by expert consensus were only recently established. PSH has predominantly been described after traumatic brain injury (TBI), in which it is associated with worse outcomes. The pathophysiology of the condition is not completely understood, although most researchers consider it to be a disconnection syndrome with paroxysms driven by a loss of inhibitory control over excitatory autonomic centres. Although therapeutic strategies to alleviate sympathetic outbursts have been proposed, their effects on PSH are inconsistent between patients and their influence on outcome is unknown. Combinations of drugs are frequently used and are chosen on the basis of local custom, rather than on objective evidence. New rigorous tools for diagnosis could allow better characterisation of PSH to enable stratification of patients for future therapeutic trials.
Topics: Autonomic Nervous System Diseases; Brain Injuries; Humans; Sympathetic Nervous System
PubMed: 28816118
DOI: 10.1016/S1474-4422(17)30259-4 -
Seminars in Neurology Oct 2020Paroxysmal sympathetic hyperactivity (PSH) is a relatively common, but often unrecognized, complication of acute diffuse or multifocal brain diseases, most frequently... (Review)
Review
Paroxysmal sympathetic hyperactivity (PSH) is a relatively common, but often unrecognized, complication of acute diffuse or multifocal brain diseases, most frequently encountered in young comatose patients with severe traumatic brain injury. It is presumed to be caused by loss of cortical inhibitory modulation of diencephalic and brain stem centers and possible additional maladaptive changes in the spinal cord that combine to produce exaggerated sympathetic responses to stimulation. The syndrome consists of repeated sudden episodes of tachycardia, tachypnea, hypertension, sweating, and sometimes fever and dystonic posturing. The diagnosis is clinical. Treatment includes reducing any external stimulation that can trigger the episodes, and starting abortive (e.g., intravenous morphine) and preventive medications (e.g., gabapentin, propranolol, clonidine). Prompt and adequate treatment of PSH may reduce the likelihood of secondary complications, such as dehydration, weight loss and malnutrition, and muscle contractures.
Topics: Autonomic Nervous System Diseases; Humans; Sympathetic Nervous System
PubMed: 32906174
DOI: 10.1055/s-0040-1713845 -
Handbook of Clinical Neurology 2019The autonomic nervous system is designed to maintain physiologic homeostasis. Its widespread connections make it vulnerable to disruption by many disease processes... (Review)
Review
The autonomic nervous system is designed to maintain physiologic homeostasis. Its widespread connections make it vulnerable to disruption by many disease processes including primary etiologies such as Parkinson's disease, multiple system atrophy, dementia with Lewy bodies, and pure autonomic failure and secondary etiologies such as diabetes mellitus, amyloidosis, and immune-mediated illnesses. The result is numerous symptoms involving the cardiovascular, gastrointestinal, and urogenital systems. Patients with autonomic dysfunction (AUD) often have peripheral and/or cardiac denervation leading to impairment of the baroreflex, which is known to play a major role in determining hemodynamic outcome during orthostatic stress and low cardiac output states. Heart rate and plasma norepinephrine responses to orthostatic stress are helpful in diagnosing impairment of the baroreflex in patients with orthostatic hypotension (OH) and suspected AUD. Similarly, cardiac sympathetic denervation diagnosed with MIBG scintigraphy or F-DA PET scanning has also been shown to be helpful in distinguishing preganglionic from postganglionic involvement and in diagnosing early stages of neurodegenerative diseases. In this chapter, we review the causes of AUD, the pathophysiology and resulting cardiovascular manifestations with emphasis on the diagnosis and treatment of OH.
Topics: Autonomic Nervous System Diseases; Humans
PubMed: 31753129
DOI: 10.1016/B978-0-12-804766-8.00008-X -
Journal of Intensive Care Medicine Feb 2017Fever is a relatively common occurrence among patients in the intensive care setting. Although the most obvious and concerning etiology is sepsis, drug reactions, venous... (Review)
Review
Fever is a relatively common occurrence among patients in the intensive care setting. Although the most obvious and concerning etiology is sepsis, drug reactions, venous thromboembolism, and postsurgical fevers are all on the differential diagnosis. There is abundant evidence that fever is detrimental in acute neurologic injury. Worse outcomes are reported in acute stroke, subarachnoid hemorrhage, and traumatic brain injury. In addition to the various etiologies of fever in the intensive care setting, neurologic illness is a risk factor for neurogenic fevers. This primarily occurs in subarachnoid hemorrhage and traumatic brain injury, with hypothalamic injury being the proposed mechanism. Paroxysmal sympathetic hyperactivity is another source of hyperthermia commonly seen in the population with traumatic brain injury. This review focuses on the detrimental effects of fever on the neurologically injured as well as the risk factors and diagnosis of neurogenic fever.
Topics: Autonomic Nervous System Diseases; Brain Injuries; Critical Care; Fever; Humans; Hypothermia, Induced; Intensive Care Units; Neurological Rehabilitation; Practice Guidelines as Topic; Risk Factors; Stroke; Subarachnoid Hemorrhage
PubMed: 26772198
DOI: 10.1177/0885066615625194 -
Movement Disorders : Official Journal... Mar 2018Dysfunction of the autonomic nervous system afflicts most patients with Parkinson disease and other synucleinopathies such as dementia with Lewy bodies, multiple system... (Review)
Review
Dysfunction of the autonomic nervous system afflicts most patients with Parkinson disease and other synucleinopathies such as dementia with Lewy bodies, multiple system atrophy, and pure autonomic failure, reducing quality of life and increasing mortality. For example, gastrointestinal dysfunction can lead to impaired drug pharmacodynamics causing a worsening in motor symptoms, and neurogenic orthostatic hypotension can cause syncope, falls, and fractures. When recognized, autonomic problems can be treated, sometimes successfully. Discontinuation of potentially causative/aggravating drugs, patient education, and nonpharmacological approaches are useful and should be tried first. Pathophysiology-based pharmacological treatments that have shown efficacy in controlled trials of patients with synucleinopathies have been approved in many countries and are key to an effective management. Here, we review the treatment of autonomic dysfunction in patients with Parkinson disease and other synucleinopathies, summarize the nonpharmacological and current pharmacological therapeutic strategies including recently approved drugs, and provide practical advice and management algorithms for clinicians, with focus on neurogenic orthostatic hypotension, supine hypertension, dysphagia, sialorrhea, gastroparesis, constipation, neurogenic overactive bladder, underactive bladder, and sexual dysfunction. © 2018 International Parkinson and Movement Disorder Society.
Topics: Autonomic Nervous System Diseases; Humans; Parkinson Disease; Synucleins
PubMed: 29508455
DOI: 10.1002/mds.27344 -
Journal of the American College of... Sep 2018Neurogenic orthostatic hypotension is a highly prevalent and disabling feature of autonomic failure due to both peripheral and central neurodegenerative diseases.... (Review)
Review
Neurogenic orthostatic hypotension is a highly prevalent and disabling feature of autonomic failure due to both peripheral and central neurodegenerative diseases. Community-based epidemiological studies have demonstrated a high morbidity and mortality associated with neurogenic orthostatic hypotension. It is due to impairment of baroreflex-mediated vasoconstriction of the skeletal muscle and splanchnic circulation and is caused by damage or dysfunction at central and/or peripheral sites in the baroreflex efferent pathway. Nonpharmacological and pharmacological interventions may be implemented to ameliorate the symptoms of orthostatic intolerance and improve quality of life. Many patients will be adequately treated by education, counseling, removal of hypotensive medications, and other nonpharmacological interventions, whereas more severely afflicted patients require pharmacological interventions. The first stage of pharmacological treatment involves repletion of central blood volume. If unsuccessful, this should be followed by treatment with sympathomimetic agents.
Topics: Algorithms; Autonomic Nervous System Diseases; Baroreflex; Blood Volume; Humans; Hypotension, Orthostatic; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Patient Education as Topic; Pure Autonomic Failure; Vasoconstriction
PubMed: 30190008
DOI: 10.1016/j.jacc.2018.05.079 -
Neurotherapeutics : the Journal of the... Oct 2020Recognition of the importance of nonmotor dysfunction as a component of Parkinson's disease has exploded over the past three decades. Autonomic dysfunction is a frequent... (Review)
Review
Recognition of the importance of nonmotor dysfunction as a component of Parkinson's disease has exploded over the past three decades. Autonomic dysfunction is a frequent and particularly important nonmotor feature because of the broad clinical spectrum it covers. Cardiovascular, gastrointestinal, urinary, sexual, and thermoregulatory abnormalities all can appear in the setting of Parkinson's disease. Cardiovascular dysfunction is characterized most prominently by orthostatic hypotension. Gastrointestinal dysfunction can involve virtually all levels of the gastrointestinal tract. Urinary dysfunction can entail either too frequent voiding or difficulty voiding. Sexual dysfunction is frequent and frustrating for both patient and partner. Alterations in sweating and body temperature are not widely recognized but often are present. Autonomic dysfunction can significantly and deleteriously impact quality of life for individuals with Parkinson's disease. Because effective treatment for many aspects of autonomic dysfunction is available, it is vitally important that assessment of autonomic dysfunction be a regular component of the neurologic history and exam and that appropriate treatment be initiated and maintained.
Topics: Autonomic Nervous System Diseases; Cardiovascular Diseases; Gastrointestinal Diseases; Humans; Hypotension, Orthostatic; Parkinson Disease; Sexual Dysfunction, Physiological
PubMed: 32789741
DOI: 10.1007/s13311-020-00897-4