In cases of autonomic dysreflexia, which of the following vital sign changes is most commonly observed?

Autonomic dysreflexia is a condition often seen in individuals with spinal cord injuries, particularly those above the T6 level. It occurs when there is an abnormal response to stimuli that typically would not cause a significant reaction. The most notable vital sign change observed in autonomic dysreflexia is severe hypertension. This occurs due to unopposed sympathetic stimulation below the level of injury, leading to vasoconstriction and an increase in blood pressure.

This hypertensive episode is usually accompanied by other symptoms such as bradycardia (slowing of the heart rate) and headache, but the hallmark sign of this condition is indeed the severe increase in blood pressure. In contrast, the other options such as bradycardia may occur but are not the primary vital sign change, and hypotension or hypothermia would not be characteristic of this condition. Therefore, the severe hypertension observed in autonomic dysreflexia is critical to recognize as it may require immediate medical intervention to address the underlying causes of the autonomic response.