Echocardiography for Differentiating Mixed Shock: A Hemodynamic Interface Approach

Abstract

Bedside evaluation of shock often relies on isolated hemodynamic variables such as arterial pressure or cardiac output, which provide incomplete insight into circulatory function. We review a physiology-based framework that conceptualizes shock as failure of energy transfer across key circulatory interfaces, guided by echocardiographic assessment. Recent work highlights the increasing recognition of mixed shock phenotypes and the limitations of traditional classification based on single parameters. Point-of-care ultrasound has emerged as a central bedside tool, enabling noninvasive evaluation of ventricular–arterial and right ventricular–pulmonary arterial coupling. Integration of echocardiographic metrics with perfusion markers such as capillary refill time allows dynamic reassessment of circulatory constraints. The four-interface model provides a structured framework to interpret shock as a system-level disturbance of circulatory coupling. Echocardiographic assessment of the ventricular interfaces supports a mechanistic bedside approach to identifying dominant hemodynamic bottlenecks and guiding individualized resuscitation.