Effectively managing fluids in the various clinical scenarios while preventing fluid overload can be challenging. Traditionally, hemodynamic management in the unstable and critically ill patient prioritizes maintaining adequate blood pressure and cardiac output. However, other factors like the arteriovenous gradient are often overlooked and play a crucial role in organ perfusion, which may be compromised by elevated venous pressure. Clinically significant organ congestion can develop in patients with right ventricular failure, pulmonary hypertension, or fluid overload. In critically ill patients, these conditions often overlap, particularly in cases of acute kidney injury.

Determining the threshold for clinically significant venous hypertension remains a challenge, with central venous pressure (CVP) measurement being and invasive technique while it still remains unclear what value of CVP is deleterious and warrants intervention. Furthermore, in conditions such as right heart failure or pulmonary hypertension, CVP may not accurately reflect the patient's true volume status. Other indirect methods of assessing venous congestion, including cumulative fluid balance, body weight fluctuations, and physical examination findings, may not correlate proportionally with systemic venous pressure.

Alternatively, venous congestion can be reliably assessed through ultrasound using the Venous Excess Ultrasound (VExUS) grading system. Ultrasound provides a rapid, non-invasive means of assessing the venous vasculature while also enabling real-time monitoring of the response to decongestive therapy. Initially developed to predict acute kidney injury in patients following cardiac surgery, the VExUS score is increasingly demonstrating utility across a variety of clinical settings.