autonomic dysreflexia

noun

: a disorder of spinal reflex activity occurring in those with spinal cord injury that is characterized by a sudden onset of hypertension, bradycardia, excessive sweating, and headache

Patients with high thoracic or cervical spinal cord lesions are at risk of autonomic dysreflexia …

—Merck Manual of Diagnosis and Therapy, 18th edition

Note: Autonomic dysreflexia results from a faulty response of the sympathetic nervous system to stimuli (as from distension of the bladder or bowel) received below the spinal cord lesion.