Challenging cases in infection prevention and control: proceedings from SHEA Spring 2025.

Hospital epidemiologists and infection prevention professionals are frequently required to make high-stakes decisions in complex clinical scenarios where evidence-based guidance is limited or absent. These decisions often carry significant implications for patient safety, healthcare worker protection, hospital operations, and legal or financial risk. This article presents three challenging cases originally featured during the "Interesting Cases" session at the Society for Healthcare Epidemiology of America (SHEA) Spring 2025 Conference, with the goal of sharing practical lessons learned and contributing to the evolving literature in healthcare epidemiology. The first case describes the intraoperative contamination of a polyethylene liner during emergency revision total hip arthroplasty, highlighting limited data guiding implant salvage and the role of antiseptic decontamination, interdisciplinary communication, and institutional preparedness. The second case examines infection prevention risks associated with a temporary hospital heating, ventilation, and air conditioning (HVAC) shutdown during a COVID-19 surge, emphasizing the use of real-time ventilation assessment tools such as carbon dioxide monitoring to guide mitigation strategies. The third case details the application of failure mode and effect analysis (FMEA) to develop an infection prevention and control policy for the educational use of non-transplant cadaveric tissue in patient care areas-an area with no existing guidelines. Collectively, these cases illustrate the realities of decision-making under uncertainty in hospital epidemiology and demonstrate how structured risk assessment, proactive planning, and cross-disciplinary collaboration can mitigate potential harm. Sharing these experiences provides practical insights and reinforces that, even in the absence of definitive guidance, systematic approaches can support safe infection prevention decision-making.