This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous System, Subject name: Surgery
[{'content': 'Intracranial pressure is not raised during \nSelect and explain. \nA. Hyperventilation, B. Status epilepticus, C. Head injury, D. Subdural hematoma', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Hyperventilation * Hyperventilation is used as a treatment with raised intracranial pressure.* Hyperventilation causes decreased PaCO2 which subsequently leads to arterial vasoconstriction thus lowering cerebral blood flow (CBF), cerebral blood volume, and intracranial pressure.Causes of ICTi) Intracranial mass (tumor)ii) Intracranial bleed (e.g. subdural hematoma, intraventricular or intracerebral)iii) Subarachnoid hemorrhage (aneurysm rupture)iv) Encephalitis/meningitsv) Head injuryvi) Status epilepticusvii) Strokeviii) Hydrocephalus", 'role': 'assistant'}]