Neurosurgical practitioners commonly utilize catheters (flexible hollow tubes) inserted into the brain for relief of pressure due to injury, tumors, blood clots, etc. Placement of such a catheter in the brain is called ventriculostomy. Ventriculostomy is associated with varying levels of internal bleeding and infectious complications. In this talk I will describe my research on ventriculostomy practices and outcomes using an Electronic Health Record (EHR) system called, the Research Patient Data Repository (RPDR). The RPDR gathers data from various hospital systems, like the Radiology Information Systems (RIS) and Hospital Information Systems (HIS), and stores it in one data warehouse. RPDR was built by Partners Healthcare Research Computing and is accessible by all faculty researchers using the RPDR online-query tool with user-defined queries on RPDR data. In this talk, I will outline the method I developed to reliably acquire data from the EHR. The method accesses patient operative reports, radiology reports, procedure billing codes, microbiology reports and discharge summaries. It uses SQL queries to find temporal relationships between the time of procedure billing, post-procedure radiology reports, and operative reports. All reports were manually reviewed for relevance to the study question and to assess data extraction measures. Discharge summaries were finally reviewed to confirm patient hospital course. After discussing the data extraction method, I will then outline the clinically relevant results and corresponding analysis of the derived patient cohort. Over an eight-year study period, 109 patients were identified that received a ventriculostomy in the operating room and a head computed tomography scan within twenty-four hours of the procedure. Analysis of the patient cohort found that patients admitted with traumatic injury were more likely to have catheters misplaced within the brain.