Autonomic hyperreflexia is an acute syndrome characterized by widespread reflex sympathetic discharge in patients with chronic spinal cord lesions. It has also been described as autonomic dysreflexia, hypertensive autonomic crisis , and neurovegetative syndrome of visceral dysfunction , as well as “mass reflex” because of its unchecked, excessive, and generalized reaction.
It appears in 85% of patients 2 to 3 weeks after the initial episode of an acute spinal lesion above the level of T7. It is produced, sometimes with remarkable ease, in response to stimuli below the level of the spinal cord lesion. These stimuli include distention of the viscera such as bladder, bowel, or intestine, cutaneous stimulation , such as tight clothing and strapping, uterine contractions, lower extremity and even upper extremity surgery , sexual intercourse , and urogenital pathology [1,4]. Urological procedures resulting in autonomic hyperreflexia include cystoscopy, urodynamic studies, extracorporeal lithotripsy, percutaneous nephrolithotomy , renal pelvic stone removal , electroejaculation , and nephrectomy .