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': 'Pulsus paradoxus is seen in- \nSelect and explain. \nA. Shock, B. Elderly, C. Emphysema/Asthma, D. High output state', 'role': 'user'}, {'content': 'Answer: C \nExplanation: * Pulsus paradoxus describes an exaggeration of the normal variation in systolic aerial blood pressure seen with respiration (normally falls by <10 mm on inspiration). * It is seen in the presence of- Airway obstruction. - Pericardial tamponade. - Massive pulmonary embolism. * Some conditions associated with pulsus paradoxus are - Constrictive pericarditis, -Restrictive cardiomyopathy, - Cardiac tamponade.', 'role': 'assistant'}]