This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
[{'content': 'Hypotension in acute spinal injury is due to: \nSelect and explain. \nA. Loss of sympathetic tone, B. Loss of parasympathetic tone, C. Orthostatic hypotension, D. Vasovagal attack', 'role': 'user'}, {'content': 'Answer: A \nExplanation: • High spinal cord injuries can also result in systemic hypotension because of loss of sympathetic tone.\n• The patient will usually have hypotension and relative bradycardia and will show evidence of good peripheral perfusion on physical examination.\n• The term neurogenic shock is used but is somewhat of a misnomer because these patients are typically hyperdynamic, with high cardiac output secondary to loss of sympathetic vascular tone.\nTreatment\n• Hypotension associated with high spinal injury can be treated by alpha-agonist phenylephrine.', 'role': 'assistant'}]