Beyond Fluid Responsiveness: Why Venous Congestion Matters in Sepsis.

Abstract

Sepsis resuscitation has traditionally been guided by a flow-centered approach aimed at restoring arterial perfusion, often leading to standardized fluid administration strategies. However, recent evidence and international guidelines increasingly support individualized fluid therapy based not only on fluid responsiveness but also on fluid tolerance. Despite this paradigm shift, the venous side of the circulation remains largely under-recognized in bedside hemodynamic assessment. Organ perfusion depends not only on arterial inflow but also on effective venous drainage, and elevated venous pressure may impair tissue perfusion and contribute to organ dysfunction even in the presence of apparently adequate systemic hemodynamics. In septic patients, capillary leakage, myocardial dysfunction, vasoplegia, and altered venous compliance may create heterogeneous hemodynamic profiles in which fluid responsiveness and venous congestion can coexist. Consequently, fluid administration may transiently improve cardiac output while simultaneously worsening tissue edema and venous congestion. Emerging ultrasound-based tools, such as the Venous Excess Ultrasound (VExUS) score, aim to integrate venous assessment into resuscitation strategies, although their role in sepsis remains incompletely defined. Recognizing fluid tolerance as a complementary component of hemodynamic evaluation may help avoid one of the most common pitfalls of sepsis resuscitation: improving flow at the expense of congestion.