This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Intravenous Anesthetic Agents, Subject name: Anaesthesia
[{'content': 'A patient was operated for right upper lobe resection. He was shifted to post awakening recovery after completion of surgery with vitals- BP 100/70 mm of Hg, HR - 94bpm, SPO2 100. After 2 hrs when he was assessed ,his vitals was BP 70/50 mm of Hg. HR-126 bpm ,SPO2 92 and surgical drain was filled with blood. Immediate re-exploration was planned. IV anaesthetic agent of choice - \nSelect and explain. \nA. Ketamine, B. Propofol, C. Thiopentone, D. Etomidate', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Acute shock IV anesthetic agent of choice ketamine. Intravenous induction agent of choice in hypotension isketamine> etomidate. Ketamine helps to maintain aerial pressure, hea rate, and cardiac output due to central stimulation of the sympathetic nervous system and inhibition of the reuptake of norepinephrine Propofol if given , lead to worsening of shock due to the profound hypotensive action of propofol because of its vasodilatory and negative inotropic effects.', 'role': 'assistant'}]