Overview

Autonomic Nervous System Testing to allow your practice to perform this crucial testing. This equipment measures galvanic skin response and Heart Rate Variability through a simple, quick, and non-invasive test that gives providers the ability to detect neuropathy before it becomes symptomatic.
Peripheral and cardiovascular neuropathy are among the largest concerns for diabetic patients , and it has been repeatedly proven that the earlier this condition can be detected and treated, the more likely a patient is to live a long and healthy life. Current estimates put the likelihood that a diabetic patient showing physical symptoms of peripheral neuropathy will survive through the next five years at between only 25 and 50 percent. By catching this condition through regular testing, health care providers can make a positive difference.

The autonomic nervous system (ANS) regulates physiologic processes, such as blood pressure, heart rate, body temperature, digestion, metabolism, fluid and electrolyte balance, sweating, urination, defecation, sexual response, and other processes. Regulation occurs without conscious control, i.e., autonomously. The ANS has two major divisions: the sympathetic and parasympathetic systems. Many organs are controlled primarily by either the sympathetic or parasympathetic system, although they may receive input from both; occasionally, functions are reciprocal (e.g., sympathetic input increases heart rate; parasympathetic decreases it).

The sympathetic nervous system is catabolic and activates fight-or-flight responses. Thus, sympathetic output increases heart rate and contractility, bronchodilation, hepatic glycogenolysis and glucose release, BMR (basal metabolism rate), and muscular strength; it also causes sweaty palms. Less immediately-life-preserving functions (e.g., digestion, renal filtration) are decreased.

The parasympathetic nervous system is anabolic; it conserves and restores. Gastrointestinal secretions and motility (including evacuation) are stimulated, heart rate is slowed, and blood pressure decreases.

Disorders of the ANS can affect any system of the body; they can originate in the peripheral or central nervous system and may be primary or secondary to other disorders. Symptoms suggesting autonomic dysfunction include orthostatic hypotension, heat intolerance, nausea, constipation, urinary retention or incontinence, nocturia, impotence, and dry mucous membranes. If a patient has symptoms suggesting autonomic dysfunction, cardiovagal, adrenergic, and sudomotor tests are usually done to help determine severity and distribution of the dysfunction.

Cardiovagal innervation testing evaluates heart rate response to deep breathing and to the Valsalva maneuver, via electrocardiogram rhythm strip. If the ANS is intact, heart rate varies with these maneuvers; the ratio of longest to shortest R-R interval (Valsalva ratio) should be 1.4 or greater.

Vasomotor adrenergic innervation testing evaluates response of beat-to-beat blood pressure to the head-up tilt and Valsalva maneuver. The head-up tilt shifts blood to dependent parts, causing reflex responses. The Valsalva maneuver increases intrathoracic pressure and reduces venous return, causing blood pressure changes and reflex vasoconstriction. In both tests, the pattern of responses is an index of adrenergic function.

Autonomic nervous system (ANS) testing, including parasympathetic function (cardiovagal innervation), sympathetic adrenergic function (vasomotor adrenergic innervation)

What Else Is The Benefit Of ANS Testing?

Diagnose the presence of autonomic neuropathy in a patient with signs or symptoms suggesting a progressive autonomic neuropathy, including:
    Diabetic neuropathy, Amyloid neuropathy, Sjogren’s syndrome, Idiopathic neuropathy, Pure autonomic failure, Multiple system dystrophy.

Evaluate the severity and distribution of a diagnosed progressive autonomic neuropathy;

Differentiate the diagnosis between certain complicated variants of syncope from other causes of loss of consciousness;

Evaluate inadequate response to beta blockade in vasodepressor syncope;

Evaluate distressing symptoms in the patient with a clinical picture suspicious for distal small fiber neuropathy in order to diagnose the condition;

Differentiate the cause of postural tachycardia syndrome;

Evaluate change in type, distribution or severity of autonomic deficits in patients with autonomic failure;

Evaluate the response to treatment in patients with autonomic failure who demonstrate a change in clinical exam;

Diagnose axonal neuropathy or suspected autonomic neuropathy in the symptomatic patient;

Evaluate and diagnose sympathetically maintained pain, as in reflex sympathetic dystrophy or causalgia; or

Evaluate and treat patients with recurrent unexplained syncope to demonstrate autonomic failure.