Update autonomic dysreflexia in patients with spinal cord injury
Spinal Cord Injury (SCI) at or above the sixth thoracic vertebral level (T6) results in damage to descending autonomic pathways, altering the parasympathetic and sympathetic control of almost every body system, including the heart, blood vessels, respiratory tract, sweat glands, bowel, urinary bladder and sexual organs. The most serious complication is autonomic dysreflexia (AD), in which a noxious stimulus below the level of injury, such as a blocked catheter or bowel distension, triggers an episode of extreme hypertension. The blood pressure dysregulation contributes to a threefold increased risk of cardiovascular disease and is the leading cause of mortality in patients with SCI.
In two reviews and an analysis of current medical practice, Prof Andrej Krassioukov and his team at the University of British Columbia, Canada have updated our knowledge about autonomic dysreflexia in patients with SCI.
• The International Autonomic Standard for SCI patients was established in 2009 and offers a convenient and useful tool to carefully screen autonomic body functions: (http://www.asiaspinalinjury.org/elearning/ASIA_Auto_Stan_Worksheet_2012.pdf).
Squait et al. showed that although autonomic dysfunction in SCI can be easily screened by this autonomic dysreflexia still is an under-recognized condition in patients with spinal cord injury. In their analysis of the adherence to international standards in clinical practice they found that a third of SCI patients was not screened for autonomic dysreflexia when admitted to rehabilitation therapy.
Assessment of clinical adherence to the international autonomic standards following spinal cord injury. Squair JW, le Nobel G, Noonan VK, Raina G, Krassioukov A. Spinal Cord 2015, 53: 668–672
• Wecht and coauthors carefully reviewed the scientific literature and updated our knowledge about the autonomic dysfunctions in SCI. Research has shown that SCI is specifically associated with changes of spinal sympathetic neurons and primary afferents. Recent studies provided additional evidence for an altered sensitivity of alpha-adrenergic receptors of the sympathetic nervous system. After urinary, bowel and sexual dysfunctions which are present in almost all individuals with SCI is the failure of blood pressure regulation a very common complication of SCI. The sudden increase in systolic BP of greater than 20–30 mmHg is considered a dysreflexic episode. Untreated episodes of AD may have serious consequences, including intracranial hemorrhage, retinal detachment, seizures and death.
Autonomic Nervous System Dysfunction Following Spinal Cord Injury: Cardiovascular, Cerebrovascular, and Thermoregulatory Effects. Wecht JM, La Fountaine MF, Handrakis JP, West CR, Phillips A, Ditor D. Current Physical Medicine and Rehabilitation Reports 2015, 3(3): 197-205.
• If correctly identified symptoms of AD can be treated with relative ease. In her review article, Helen Cowan presents a practical and easy to apply algorithm for the immediate treatment of autonomic dysreflexia with hypertensive crisis.
Nursing Times 28.10.15 / Vol 111 No 44 / www.nursingtimes.net.
Clinicians are strongly encouraged to assess basic autonomic functions after SCI and to introduce its use into standard clinical practice. Patients with spinal cord injury and their families should be educated to monitor blood pressure, to recognize the early symptoms, and to avoid trigger of autonomic dysreflexia.
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