This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Surgery
[{'content': 'An elderly man presented with sigmoid volvulus, is successfully detorsed. What is the next step to be done? \nSelect and explain. \nA. Observation for recurrence, B. Resection immediately, C. Resection if volvulus recurs, D. None of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: (A) Observation for recurrence # Sigmoid volvulus is the most common form of volvulus of the gastrointestinal tract and is responsible for 8% of all intestinal obstructions.> Decompression may be achieved with the introduction of a stiff tube per the rectum, aided by endoscopy or fluoroscopy.> If rectal decompression is instituted, the patient should be observed for persistent abdominal pain and bloodstained stools, signs that may herald ischemia and indicate the need for surgical intervention.> Surgery is reserved for patients in whom tube decompression fails or for those in whom signs of ischemia are suggested.', 'role': 'assistant'}]