Diagnosis and management of autonomic disorders

Abstract

Clinically it is very important to diagnose and treat autonomic symptoms such as syncope, urinary problems and sweat abnormalities. Vasovagal syncope, the most common syncopal disorder, usually develops under 40 years old. As the sensitivity of head–up tilt test is low, history taking is more important for the diagnosis. Carotid sinus syncope usually develops over 60 years old and its diagnosis is confirmed based on the evidence of bradycardia and hypotension induced by stimulation to the carotid sinus. Orthostatic hypotension is defined as a sustained reduction of systolic blood pressure of at least 20mmHg or diastolic blood pressure of 10mmHg within 3 minutes of standing or during head–up tilt test. Non–pharmacological management is important : salt supplementation, fluid intake and avoiding precipitating factors such as high carbohydrate meals, hot environments, alcohol and vasodilator drugs. Vasopressor drugs, which are used for treatment of orthostatic hypotension, can cause or aggravate recumbent hypertension. Urinary dysfunction is classified into storage and voiding symptoms. Anticholinergic drugs, which are used for treatment of storage symptoms, may exacerbate cognitive impairment. In regard to impaired voiding, clean intermittent selfcatheterization is preferred in patients having over 100ml of residual urine. Sudomotor abnormalities include hyperhidrosis and hypo/anhidrosis. For focal hyperhidrosis such as palmoplantar hyperhidrosis treatment like aluminium chloride application, tap water iontophoresis and thoracic sympathectomy may be performed. For acquired idiopathic generalized anhidrosis corticosteroid therapy is often effective.