ARISE framework: a temporal, multi-organ view of perfusion in sepsis

Sepsis is a critical illness characterized by pronounced temporal dynamics and marked heterogeneity of organ perfusion. Current hemodynamic management relies largely on global macro-circulatory variables such as MAP and CO, but these measures provide limited insight into inter-organ blood-flow redistribution and often fail to detect occult hypoperfusion in vulnerable tissues. Consequently, organ dysfunction may continue to progress even when systemic targets appear to be achieved. The arterial resistance index (RI) can be repeatedly assessed in specific organs with relatively high temporal resolution, it provides a practical signal for tracking perfusion heterogeneity in sepsis. On this basis, this review reframes sepsis as a process dominated by dynamic blood-flow redistribution rather than a single, homogeneous state of circulatory failure and proposes the Arterial Resistance Index Series in Echography (ARISE) framework. ARISE focuses on four representative vascular beds that capture key dimensions of circulatory regulation-including central control, vulnerable organs, and peripheral perfusion: the cerebral, renal, and superior mesenteric arteries, as well as the anatomical snuffbox artery. The framework emphasizes RI trajectories over time, inter-organ flow distribution, and the structured integration of these patterns. Available evidence indicates that arterial RI in different organs exhibits pronounced temporal variation and inter-organ heterogeneity during sepsis. Distinct trajectories are observed across central, vulnerable, and peripheral vascular beds, reflecting ongoing redistribution of blood flow as the disease evolves. Multi-organ RI assessment can reveal pathophysiological phenomena not captured by conventional macro-circulatory indices, including occult hypoperfusion, macro-microcirculatory uncoupling, and "sacrificial" redistribution. Advances in critical care ultrasonography now enable bedside, real-time, quantitative monitoring of multi-organ RI, providing the technical foundation for dynamic perfusion assessment. Overall, ARISE shifts sepsis assessment from a static pressure-flow paradigm to a dynamic framework centered on organ blood-flow distribution and evolving perfusion patterns.