This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Trauma, Subject name: Surgery
[{'content': 'All are indications for CT in a head injury patient except \nSelect and explain. \nA. Focal neurological deficit, B. GCS <13 at presentation, C. An episode of vomiting, D. Patient is on warfarin', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Indications for CT imaging within 1 hourGCS <13 at any pointGCS <15 at 2 hoursFocal neurological deficitSuspected open, depressed or basal skull fractureMore than one episode of vomitingPost-traumatic seizureIndications for CT imaging within 8 hoursAge >65 yearsCoagulopathy (e.g. aspirin, warfarin or rivaroxaban use)Dangerous mechanism of injury (e.g. fall from a height, road traffic accident)Retrograde amnesia >30 minutesBailey and love 27e 330', 'role': 'assistant'}]