testing the sympathetic nervous system
Last reviewed 01/2018
There are several ways of testing the integrity of the sympathetic nervous system:
- postural blood pressure changes: there is normally a slight rise in blood pressure on standing; in patients with sympathetic denervation, there is a marked fall.
- the Valsalva manoeuvre: there is a temporary fall in blood pressure in patients with autonomic failure.
- tests of positive efferent sympathetic function:
- a rise in blood pressure during times of stress or application of an ice-pack.
- reflex sweating and flushing of skin are still intact