Unifying Fluid Responsiveness and Tolerance With Physiology: A Dynamic Interpretation of the Diamond–Forrester Classification

Abstract

Point ically twinedof unstable careconceptsultrasound patients, such as:(POCUS) however, “flow,” “congestion,”is there a first-line is confusion “fluidtool toresponsivenessassess surrounding hemodynam-(FR),” inter- and “fluid tolerance.” We argue that the Frank–Starling relationship is clarifying because it describes the interplay between “congestion” and “flow” on the x-axis and y-axis, respectively. Nevertheless, a single, simultaneous assessment of congestion and flow via POCUS remains a static approach. To expand this, we propose a two-step process. The first step is to place the patient on an ultrasonographic Diamond–Forrester plot. The second step is a dynamic assessment for FR (e.g., passive leg raise), which individualizes therapy across the arc of critical illness.