Measurement and interpretation of central venous pressure: a narrative review.

Introduction: Central venous pressure has been a key component of haemodynamic monitoring for several decades, but its clinical utility is still debated. While central venous pressure has been used traditionally to assess intravascular volume status and fluid responsiveness, mounting evidence suggests that its absolute value alone is an unreliable predictor of such states. This narrative review explores the historical development and physiological foundations of central venous pressure, its measurement techniques and the available evidence regarding central venous pressure monitoring in various clinical scenarios.

Methods: We conducted a literature search to identify relevant articles. The abstracts of identified articles were assessed for relevance, and their references were screened for further relevant publications.

Results: We identified 229 articles, with 72 undergoing full text extraction and data synthesis. Preliminary work in central venous pressure monitoring began in canines, before early human studies and the development of Guytonian principles of haemodynamics. Physiologically, central venous pressure reflects intraluminal pressure of the superior vena cava, with measurement affected significantly by transducer position, catheter position and intrathoracic pressures. In right ventricular dysfunction, the central venous pressure waveform loses its x-descent, as the y-descent becomes exaggerated. Central venous pressure in isolation is considered a poor predictor of volume responsiveness; however, elevated central venous pressure is linked with impaired tissue perfusion and poor clinical outcomes, including acute kidney injury and higher risk of mortality in certain patient cohorts.

Discussion: Although reliance on central venous pressure as a singular guide for fluid resuscitation is discouraged, it remains a valuable tool when interpreted in conjunction with waveform analysis and trend monitoring, offering insights into right heart function, venous congestion and organ perfusion. As patient cohorts grow increasingly complex, a nuanced understanding of central venous pressure waveforms and trends is essential for optimising management strategies in peri-operative and critical care settings.