ASSESSMENT OF AUTONOMIC DYSREFLEXIA IN PATIENTS WITH SPINAL-CORD INJURY

Objectives and methods-To assess the impairment of supraspinal control over spinal sympathetic centres and the occurrence of autonomic dysre flexia in patients with spinal cord injury. Autonomic dysreflexia is c aused by the disconnection of spinal sympathetic centres from supraspi nal control and is characterised by paroxysmal hypertensive episodes c aused by non-specific stimuli below the level of the lesion. Therefore , patients with spinal cord injury were examined clinically and by dif ferent techniques to assess the occurrence of autonomic dysreflexia an d to relate disturbances of the sympathetic nervous system to episodes of autonomic dysreflexia. Results-None of the paraplegic patients, bu t 59% (13/22) of tetraplegic patients (91% of the complete, 27% of the incomplete patients) presented signs of autonomic dysreflexia during urodynamic examination. Only 62% of the tetraplegic patients complaine d about symptoms of autonomic dysreflexia. Pathological sympathetic sk in responses (SSRs) of the hands were related to signs of autonomic dy sreflexia in 93% of cases. No patient with preserved SSR potentials of the hands and feet showed signs of autonomic dysreflexia, either clin ically or during urodynamic examination. Ambulatory blood pressure mea surements (ABPMs) indicated a loss of circadian blood pressure rhythm (sympathetic control) but preserved heart rate rhythm (parasympathetic regulation) only in patients with complete tetraplegia. Pathological ABPM. recordings were seen in 70% of patients with symptoms of autonom ic dysreflexia. Conclusions-The urodynamic examination was more sensit ive in indicating signs of autonomic dysreflexia in patients with spin al cord injury, whereas SSR allowed the assessment of the degree of di sconnection of the sympathetic spinal centres from supraspinal control . Using ABPM recordings the occurrence of episodes of autonomic dysref lexia over 24 hours and the effectiveness of therapeutical treatment c an be assessed.