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DictionarySeeautonomicautonomic dysreflexia
autonomic [aw″to-nom´ik] not subject to voluntary control.autonomic dysreflexia an uninhibited and exaggerated reflex of the autonomic nervous system" >autonomic nervous system to stimulation; called also hyperreflexia. The response occurs in 85 per cent of all patients who have spinal cord injury above the level of the sixth thoracic vertebra. It is potentially dangerous because of attendant vasoconstriction and immediate elevation of blood pressure, which in turn can bring about hemorrhagic retinal damage or stroke syndrome. Less serious effects include severe headache; changes in heart rate; sweating, flushing, and “goose bumps” or piloerection above the level of the spinal cord injury; and pallor below that level.Patient Care. Circumstances that can trigger autonomic dysreflexia are often related to stimulation of the bladder, bowel, and skin of the patient. Examples are a distended bowel or bladder, pressure on the skin, or any of a number of noxious stimuli. Once the symptoms of autonomic dysreflexia are manifest, emergency care is indicated. Efforts are made to lower the blood pressure by placing the patient in a sitting position or elevating the head and upper body to a 45-degree angle. The stimulus must be identified and removed as gently and quickly as possible. If fecal impaction is the cause, the rectum should be coated with an anesthetic ointment prior to attempted removal of the impaction; this prevents increasing the stimulus to autonomic dysreflexia. The physician is notified so that appropriate medical intervention can be initiated. Antihypertensive drugs are a last resort. As soon as the cause is identified and removed, the dysreflexia will disappear. Patients who experience repeated attacks may require surgery to sever the nerves responsible for the exaggerated response to stimulation.autonomic nervous system the branch of the nervous system that works without conscious control. The voluntary nervous system governs the striated or skeletal muscles, whereas the autonomic nervous system governs the glands, cardiac muscle, and smooth muscles such as those of the digestive system, respiratory system, and skin. The autonomic nervous system is divided into two subsidiary systems, the sympathetic nervous system and the parasympathetic nervous system. See Plate 14.
dysreflexia [dis″re-flek´se-ah] a condition of disordered response to stimuli.autonomic dysreflexia 1. an uninhibited and exaggerated response of the autonomic nervous system to stimulation, as seen in many patients with high spinal cord injuries; see also autonomic dysreflexia.2. a nursing diagnosis accepted by the North American Nursing Diagnosis Association, defined as a life-threatening uninhibited sympathetic response of the nervous system to a noxious stimulus after a spinal cord injury at T7 or above.autonomic dysreflexia A potentially life-threatening condition most common in patients with spinal cord injuries above T6, but which may occur with lesions as low as T10. Clinical findings Severe paroxysmal hypertension accompanied by throbbing headaches, profuse sweating, nasal stuffiness, flushing of the skin above thelesion, bradycardia, apprehension and anxiety.autonomic dysreflexia Neurology A potentially life-threatening ↑ in BP, sweating, and other autonomic reflexes in reponse to various stimuli–eg, bowel impaction. See Autonomic failure. au·to·no·mic dys·re·flex·ia (aw'tō-nom'ik dis-rē-flek'sē-ă) A syndrome occurring in some people with spinal cord lesions resulting from functional impairment of the autonomic nervous system. Symptoms include hypertension, bradycardia, severe headaches, pallor below and flushing above the cord lesion, and convulsions. Synonym(s): autonomic hyperreflexia. [G. autos, self + nomos, law; dys, difficult at + L. reflectere, to bend back]au·to·no·mic dys·re·flex·ia (aw'tō-nom'ik dis-rē-flek'sē-ă) A syndrome occurring in some people with spinal cord lesions resulting from functional impairment of the autonomic nervous system. |