401: FROM OUTBREAK TO OUTCOME: PROTOCOLIZED ICU CARE IMPROVED SURVIVAL IN THE 2024-2025 COLOMBIA OUTBREAK

Introduction: During the 2024/2025 epidemic in Colombia, yellow fever (YF) reemerged with high lethality in unvaccinated populations, overwhelming the local response. In this context, we developed and implemented a protocolized critical care strategy based on a national expert consensus. Recognizing the pathophysiology of severe yellow fever (SYF), characterized by cytokine-driven endothelial injury and viral sepsis, we designed an approach focused on immunologic containment and organ support while awaiting inflammatory stability. Our objective was to improve survival by standardizing ICU admission, early support, and evidence-based interventions in resource-limited, epidemic-prone settings. Methods: In response to the 2024–2025 yellow fever epidemic in Tolima, a national expert consensus was urgently implemented at Hospital Federico Lleras Acosta, the designated referral center. A protocolized ICU bundle was applied, including standardized admission, restrictive fluids with vascular recruitment, neurological monitoring, and early use of plasmapheresis combined with corticosteroid-based immunosuppression. After implementation, clinical, lab, and outcome data were collected from all confirmed SYF cases. Primary outcome was in-hospital mortality; secondary outcomes included organ support and complications. Artificial intelligence was ethically used to support grammar and stylistic optimization during manuscript preparation. Results: 53 patients with SYF were admitted to the ICU. After protocol implementation, mortality dropped to 35% versus historical rates over 70%. Early immunomodulation, vasopressors, and fluid restriction reduced refractory shock and complications. No serious adverse events were observed. Median ICU stay was 7 days (IQR 5–11). Conclusions: In tropical regions with high arboviral incidence and transient endemicity, implementing a protocolized ICU strategy improved survival and reduced complications in severe yellow fever. This model offers a replicable framework for critical care in future outbreaks affecting vulnerable, unvaccinated populations.