This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Regional anaesthesia, Subject name: Anaesthesia
[{'content': 'In high spinal anaesthesia what is seen - \nSelect and explain. \nA. Hypotension & Bradycardia, B. Hypotension & Tachycardia, C. Hypeension & Bradycardia, D. Hypeension & Tachycardia', 'role': 'user'}, {'content': 'Answer: A \nExplanation: High spinal anaesthesia involving T4 thoracic segment blocks sympathetic autonomic fibres for hea resulting in vagal dominance. Hence, hypotension and bradycardia occur.', 'role': 'assistant'}]