Table 8

Outline of investigations in autonomic diseases

*Indicates screening autonomic tests used in our London Unit.
Adapted from Mathias CJ, Bannister R, eds. Investigation of autonomic disorders. In: Autonomic failure: a textbook of clinical disorders of the autonomic nervous system, 4th ed. Oxford: Oxford University Press, 2002: 342–56.
    PhysiologicalHead-up tilt (60°)*; standing*; Valsalva maneouvre*
Pressor stimuli* (isometric exercise, cutaneous cold, mental arithmetic)
Heart rate responses—deep breathing*, hyperventilation*, standing*, head-up tilt*, 30:15 R-R interval ratio
Liquid meal challenge
Modifed exercise testing
Carotid sinus massage
    BiochemicalPlasma noradrenaline: supine and head-up tilt or standing; urinary catecholamines; plasma renin activity, and aldosterone
    PharmacologicalNoradrenaline: α adrenoceptors, vascular
Isoprenaline: β adrenoceptors, vascular and cardiac
Tyramine: pressor and noradrenaline response
Edrophonium: noradrenaline response
Atropine: parasympathetic cardiac blockade
▸EndocrineClonidine—α 2 adrenoceptor agonist: noradrenaline suppression; growth hormone stimulation
▸SudomotorCentral regulation—thermoregulatory sweat test
Sweat gland response to intradermal acetylcholine, quantitative sudomotor axon reflex test (Q-SART), localised sweat test
Sympathetic skin response
▸GastrointestinalVideo-cinefluoroscopy, barium studies, endoscopy, gastric emptying studies, transit time, lower gut studies
▸Renal function and urinary tractDay and night urine volumes and sodium/potassium excretion
Urodynamic studies, intravenous urography, ultrasound examination, sphincter electromyography
▸Sexual functionPenile plethysmography
Intracavernosal papaverine
Sleep studies to assess apnoea and oxygen desaturation
▸Eye and lacrimal functionPupillary function, pharmacological and physiological
Schirmer’s test