Real-Time Decision Support for Improving Intraoperative Cerebral Perfusion Pressure

This will be a single-center study taking place at the University of Michigan Health System, Ann Arbor, MI. The study has been approved by the University of Michigan Medical School Institutional Review Board (IRBMED). Automated pager alert protocols have been previously published from the investigators' department, and this alerting system is used for operational purposes on a daily basis. Surgical patients will be automatically screened using a designed script from the anesthesia information management system (Centricity, Wishahaka, WI). The script will screen for active surgical patients with intracranial pressure (ICP) data recording in our hospital's non-cardiac operating rooms. When these data are captured, an automated enrollment process will occur if the following electronic charting criteria are met: * Age ≥ 18 years old * Case identified as a general anesthetic * Non-intracranial aneurysm surgery * Non-pregnant patient After "anesthetic induction end" time is documented within the case, the alerting system will turn on after a 10-minute grace period. The alerting system will then retroactively measure median CPP values over 5-minute epochs, and if median CPP is \< 60 mmHg, the following alphanumeric pager alert will be delivered: "Patient: LAST NAME, FIRST NAME, OR(N), has a cerebral perfusion pressure \< 60 mmHg. Disregard alert for intracranial aneurysm cases or if patient is pregnant." This alert will be delivered twice total (if criteria are met). The aim of the pager alerts will be to relay information regarding cerebral ischemia risk between when CPP decreases below 60 mmHg. Final clinical decision-making, however, will be left to the anesthesia team. The pager alerts will not otherwise compel action, and no other recommendations will be made.