Ultrasound as the New Stethoscope: A Journey From Just Locating Fluid to Assessing Haemodynamics and Venous Congestion.

Point-of-care ultrasound (POCUS) has evolved from a simple tool for fluid localization to a comprehensive modality for hemodynamic assessment and real-time clinical decision-making. The Bedside Lung Ultrasound in Emergency (BLUE) protocol enables clinicians to diagnose causes of cardiorespiratory failure more accurately than clinical examination alone. In patients presenting with shock and hypotension, POCUS facilitates rapid identification of the underlying aetiology. This allows for targeted treatment in these critically ill patients. In complex patients presenting with concurrent cardiac failure and renal dysfunction, the venous excess ultrasound (VExUS) score provides a valuable assessment of volume status, guiding fluid management and therapeutic interventions. The increasing availability of handheld ultrasound devices, cloud-based services and artificial intelligence (AI) is driving POCUS beyond the traditional hospital settings into the community. Associated healthcare professionals already perform initial scans in community settings with remote expert review. In future models of care, patients or carers could use AI-assisted handheld devices to enable self-monitoring and early disease management at home. This review examines the expanding role of POCUS in acute and critical care settings, with a focus on key protocols that enhance diagnostic accuracy and guide clinical management, and considers future expansion of POCUS into the community.