Autonomic Dysreflexia
Autonomic dysreflexia (AD) is an acute syndrome of excessive, uncontrolled sympathetic output with potentially serious consequences that can occur in patients who have had an injury to the spinal cord. It is typically seen in patients with injury levels at or above T6 and particularly in complete injuries. A noxius or non noxius stimulus below the level of the lesion produces AD. The most common sources of the stimulus to the cord are bladder distention and fecal impaction. The sympathetic nerves prevail below the level of injury, and the parasympathetic nerves prevail above the level of injury. The symptoms, which a patient usually presents with, include hypertension, headache, sweating, flushing, nasal congestion above level of lesion. The headache is usually pounding in nature. Pallor and coldness is seen in the lower extremities because of sympathetic overactivity leading to vasoconstriction below the lesion. Piloerection occurs below the injury level owing to sympathetic stimulation of hair follicles. Possible complications of AD include retinal hemorrhage, intracerebral hemorrhage, myocardial infarction, convulsion, and potentially death. Once the inciting stimulus is removed, the reflex hypertension resolves.
Keywords : Spinal cord injury; autonomic dysreflexia; hypertensio