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': 'Which of the following can cause secondary brain injury \nSelect and explain. \nA. Hypoxia, B. Intracranial pressure > 30mm Hg, C. Hypotension, D. All of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Causes of secondary brain injury\n- Hypoxia: PO2 < 8 kPa\n- Hypotension: systolic blood pressure (SBP) < 90 mmHg\n- Raised intracranial pressure (ICP): ICP > 20 mmHg\n- Low cerebral perfusion pressure (CPP): CPP < 65 mmHg\n- Pyrexia\n- Seizures\n- Metabolic disturbance', 'role': 'assistant'}]