Hello, This issue requires immense details pertaining to his preoperative medical condition, per operative and postoperative details from a medical point of view as there can be an issue with cerebral circulation from prolonged hypotension giving ischemic infarction, acute thrombosis emboli issues from systemic circulation or surgery related and so forth. The best predictor would be an MRI of the brain and other supportive vital parameters to guide ahead regarding the prognostic factors and recovery chances. Hope I have answered your query. Let me know if I can assist you further. Take care Regards, Dr Purva Patel, General & Family Physician