Inferior Vena Cava Diameter and Collapsibility Index measurements by Ultrasound and its Correlation with Central Venous Pressure in Critically Ill Patients

Abstract

Background : The diagnosis and treatment of critically ill patients depend on an accurate evaluation of intravascular volume status. An intrusive tool used for this is central venous pressure (CVP). Aim : In the present investigation, intravascular volume status of severely ill patients was evaluated using noninvasive inferior vena cava (IVC) diameter and collapsibility index (CI) measurements in ICU patients and its link with CVP. Patients and methods : A total of 100 adult patients hospitalized to the medical ICU were included in this study. CVP was measured by an intrathoracic venous catheter in the right atrium. The IVC-CI was calculated by measurement of IVC diameter in expiration and inspiration by bedside ultrasound. Results : The IVC dmin and IVC dmax decreased in hypovolemic patients compared with euvolemic and hypervolemic patients. However, IVC-CI showed a signi fi cant increase in hypovolemic patients. CVP showed a signi fi cant positive correlation with IVC diameter with expiration and inspiration but had a negative correlation with the IVC-CI. Conclusion : IVC diameters and collapsibility index have a signi fi cant correlation with CVP. Its measurements by ultrasound are simple, noninvasive, safe methods for evaluation of volume status versus CVP in critical patients.