Autonomic dysreflexia occurs in spinal cord injuries at or above which level?

• A. T6 or higher
• B. L1 or higher
• C. C7 or higher
• D. T12 or higher

Answer: (A)

High spinal cord injuries disrupt the brain’s ability to dampen the sympathetic reflexes that run below the injury. When the injury is at or above T6, a noxious stimulus below the level of injury (such as bladder distension or bowel issues) can trigger a massive, unregulated sympathetic discharge. This causes widespread vasoconstriction below the lesion and a dangerous rise in blood pressure. The parasympathetic system can respond above the level of injury (often seen as bradycardia or flushing above the lesion), but it cannot counteract the intense sympathetic activity below the injury. If the injury is below T6, descending control is less compromised, making this syndrome much less likely. So autonomic dysreflexia occurs with spinal cord injuries at or above T6.