Can Bedside Ultrasonography of Internal Jugular Vein Replace Ultrasonography of Inferior Vena Cava for Volume Status Estimation?

Abstract

Introduction Estimation of haemodynamic status of acute and critically ill patients at Accident & Emergency (A&E) Departments is important. Measurement of inferior vena cava (IVC) diameter and collapsibility index by bedside ultrasound (USG) was known to correlate well with volume status of these patients. However, the value of similar estimation based on USG measurement of internal jugular vein (IJV) diameter was seldom studied. Whether USG measurement of IJV diameter can replace that of IVC diameter was unknown. Methods This was a cross-sectional study using a convenience sample of healthy volunteers among staff of a local A&E. The diameter of IJV and IVC (IJVD and IVCD) of the 51 participants were measured by bedside USG. The corresponding collapsibility index (CI) of IJV and IVC were then calculated. The correlation between IJVD and IVCD was assessed by the use of Bland-Altman plot. Results Median value of IVC-CI and of IJV-CI was 29.41% and 17.12% respectively. The mean of the difference of measurement of IJV-CI and IVC-CI was −11.10% (95% Confidence Interval: −15.27 to −6.92). The limits of agreement of the above difference were −40.77% and 18.58%. The range of these limits was too wide. Conclusion Because the range of limits of agreement between IJV-CI and IVC-CI were too wide, IJV-CI may not be used as an alternative to IVC-CI for the estimation of the volume status of normal adults.