Biofilm Formation on Invasive Medical Devices in Adult Intensive Care Units: A Scoping Review of Biomedical and Clinical Evidence

Background/Objectives: Biofilm formation on invasive medical devices represents a major challenge in intensive care units (ICUs), contributing to device-associated infections, antimicrobial resistance, and adverse clinical outcomes. Despite its clinical relevance, the extent and characteristics of the available evidence on biofilm formation in invasive medical devices used in adult ICUs remain heterogeneous and incompletely mapped. The objective was to map and characterize the available evidence on biofilm formation in invasive medical devices used in adult ICUs. Methods: A scoping review was conducted following PRISMA-ScR guidelines. The review was structured using the Population–Concept–Context (PCC) framework. A comprehensive search was performed in PubMed, Scopus, Web of Science, Embase, and ScienceDirect. Primary studies evaluating biofilm formation on invasive medical devices in adult ICUs were included. Data were extracted on study characteristics, device type, microorganisms, biofilm detection methods, and clinical outcomes. Results were synthesized descriptively and presented through tables and an evidence map. Results: Sixteen studies met the inclusion criteria. Evidence was primarily focused on endotracheal tubes, vascular catheters, and urinary catheters. Biofilm formation was consistently documented across these devices, involving Gram-negative bacteria, Gram-positive cocci, and fungal pathogens. Detection methods were heterogeneous, with early reliance on electron microscopy and increasing use of quantitative phenotypic assays, while molecular approaches remained limited. The evidence map revealed a concentration of studies in vascular devices and significant methodological variability across studies. Conclusions: Biofilm formation on invasive medical devices in adult ICUs is a clinically significant and microbiologically complex phenomenon. The available evidence highlights key device categories and pathogen profiles but is limited by methodological heterogeneity and gaps in molecular characterization and translational research. Future studies should prioritize standardized, multimodal approaches and clinically oriented designs to improve prevention and management of device-associated biofilm infections in critical care settings.