Despite extensive literature on patient safety (PS) and operating room crew resource management, the intersection between critical events during brachytherapy (BT) and fundamentals of PS are not well described. Radiation oncology (RO) quality and safety are commonly approached from a physics and dosimetry perspective, creating a need to better understand issues impacting quality of care and safety in BT. This study uses a mixed-methods approach to incident analysis of PS events and process improvement (PI) opportunities, reported during BT, to identify and quantify errors, inefficiencies and workflow interruptions. The purpose is to describe the current landscape and allow for multidisciplinary development of adaptive interventions toward more efficient and safer BT practices. Safety reports [SR: PS events] and glitch logs [GL: PI opportunities], submitted by multidisciplinary team members, were retrospectively reviewed from a prospectively collected database at a large, tertiary cancer center providing high-volume BT services. The study spanned from 9/2014 - 12/2019. Events were quantified by patterns of occurrence. Review of SR/GL narratives were done to qualitatively analyze events for recurrent themes. A total of 2,455 patients received 7,606 fractions between 2014 and 2019. There were 105 events, accounting for 4.28% of all patients and 1.38% of all fractions (none were state/NRC reportable). Four predominant recurring themes were seen (Table 1): (1) equipment concerns (inappropriate use, failure, missing/broken), (2) human factors (poor communication, handoffs, cross coverage, unclear roles/responsibilities, training/experience), (3) workflow inefficiencies (scheduling, coordination, new processes, transport, room turnover) and (4) electronic documentation (software, planning, manual data entry, information transfer). Human factors were the most common category of events documented: SR (42.9%) and GL (37.1%). Number of events reported was higher from July through December in every year (in aggregate, these represented 70% of SR and 60% of GL). During reporting, two safety systems were put into place from sentinel events: (1) a checklist to prevent retained foreign objects and (2) a team checklist for high-risk significant bleeding following interstitial implant removal. In-depth evaluation of errors and inefficiencies by multidisciplinary teams in BT may lead to better understanding and implementation of PS procedures and PI strategies for BT delivery. Multidisciplinary teams are critical in providing perspectives for addressing common workflow issues and innovative solutions for patient care, with the potential for implementation at other BT capable institutions.Abstract 2449; TableEvent Characteristics & Predominant Themes by Category NumberPredominant Themes in SR/GLCombined Events n = 105119 (18.1%) [11.3%,26.8%]243 (41.0%) [31.5%,51.0%]328 (26.7%) [18.5%,36.2%]415(14.3%) [8.2%-22.5%] Open table in a new tab