Assessment of accuracy and applicability of PiCCO in circulating blood volume management: a clinician’s perspective

Abstract

Monitoring with the PiCCO technology (Pulse Contour Cardiac Output) has become a widely adopted method for hemodynamic assessment and fluid management in critically ill patients. The technique combines transpulmonary thermodilution and pulse contour analysis to provide continuous or intermittent measurements of cardiac output, global end-diastolic volume index (GEDVI), extravascular lung water index (EVLWI), and systemic vascular resistance index (SVRI). Despite its technological sophistication and broad clinical use, the validity, reproducibility, and universal applicability of PiCCO-derived data remain subject to ongoing debate. Particular concern arises in clinical scenarios involving altered physicochemical properties of blood, vascular dysregulation, vasoplegia, or hypoproteinemia, where thermodilution-based calculations may become inaccurate. Furthermore, neurohumoral and reflex circulatory mechanisms - such as the Schwik-Larin reflex - are not accounted for in the PiCCO model, yet may significantly impact hemodynamic dynamics and confound interpretation. This review provides a critical analysis of the methodological, physiological, and clinical limitations of PiCCO monitoring. Special emphasis is placed on the influence of blood rheology, temperature, microcirculatory changes, and endothelial dysfunction on the reliability of computed hemodynamic variables. The necessity of an integrative approach to data interpretation is emphasized, involving the correlation of PiCCO-derived parameters with the clinical picture, laboratory findings, therapeutic response, and the patient's pathophysiological status. In conclusion, PiCCO remains a potentially valuable tool in critical care; however, its effective use requires clinical vigilance, awareness of physiological constraints, and individualized therapeutic decision-making, particularly in fluid management strategies.