Abstract
<title>Abstract</title> <p>Background Critical care in Brazil's Unified Health System (SUS) is constrained by a limited intensivist workforce, geographic inequities, and heterogeneous quality. Although Tele-ICU benefits high-income settings, evidence on the feasibility, fidelity, and sustainability of large-scale implementation in resource-constrained public systems is scarce. We describe a nationally coordinated Tele-ICU initiative supported by the Brazilian Ministry of Health. Methods A mixed-methods implementation evaluation was conducted across public hospitals in eight Brazilian states and three macroregions (Northeast, Central-West, Southeast) from May 2022 to December 2023. The core intervention comprised structured daily multidisciplinary virtual rounds, complemented by continuing education and systematic data monitoring. Implementation outcomes were assessed with the RE-AIM framework (Reach, Adoption, Implementation fidelity, Maintenance) and qualitative data through the Consolidated Framework for Implementation Research (CFIR). Clinical process indicators were monitored descriptively as contextual signals rather than effectiveness outcomes. Results We conducted 3,892 telerounds encompassing 16,123 case discussions involving 3,040 unique ICU patients (mean 5.3 per patient). Continuing education comprised 15 virtual learning sessions and 11 thematic campaigns, reaching 1,933 and 701 professionals—all onboarded sites initiated activities, indicating universal initial adoption. Fidelity was high: 84% mean adherence to scheduled telerounds, 100% multidisciplinary participation (≥ 3 professional categories) in completed sessions, and 92% checklist use. Sustained participation was heterogeneous; three hospitals (four ICU units) evolved spontaneously into regional peer-learning hubs that mentored neighboring institutions and disseminated adapted protocols. Exploratory indicators remained within national benchmarks (mean ICU length of stay: 10 days; crude mortality: 30%), with no adverse trends. CFIR analysis identified leadership engagement, adaptability, and interprofessional trust as key facilitators, and staff turnover, connectivity constraints, and competing priorities as principal barriers. Conclusions Large-scale Tele-ICU implementation within Brazil's public system is feasible and can achieve high fidelity across diverse hospitals. Combining centralized expertise with locally adaptive, education-centered workflows supported sustained delivery without compromising core components.</p>