Value of the ratio of internal jugular vein to common carotid artery cross-sectional area measured by bedside ultrasound in the evaluation of volume responsiveness in critical patients

Objective To discuss the value of the ratio of internal jugular vein(IJV) to common carotid artery(CCA) cross-sectional area measured by bedside ultrasound in the evaluation of volume responsiveness in critical patients.

Methods Fifty critical patients were divided into the negative volume response group(ΔCO < 15%, n=20) and positive volume response group(ΔCO≥15%, n=30) according to the cardiac output change(ΔCO) after passive leg lift (PLR) test.The diameter and cross-sectional area of IJV and CCA in two groups were measured by bedside ultrasound, and the ratio of IJV to CCA cross-sectional area was calculated, and the correlation between IJV/CCA cross-sectional area ratio and ΔCO after PLR test was analyzed.The accuracy and threshold of the ratio of IJV/CCA cross-sectional area and ΔCO value in predicting the volumetric reactivity were evaluated by ROC curve.

Results The diameter and cross-sectional area of IJV(14.03±4.877)mm and (100.40±60.91)mm² were negatively correlated with the ΔCO value(P < 0.05), and the diameter and cross-sectional area of CCA(8.35±1.60)mm and (57.64±18.50)mm² were not correlated with the ΔCO value(P>0.05).The ratio of IJV/CCA cross-sectional area in positive volume response group was significantly less than that in negative volume response group(P < 0.01), and the ratio of IJV/CCA cross-sectional area was negatively correlated with the ΔCO value(P < 0.01).At the IJV/CCA cross-sectional area ratio of 1.66, the sensitivity and specificity was 87.1% and 79.6%, respectively, and the areas under the ROC curve was 0.836(95%CI:0.710-0.952).

Conclusions The bedside ultrasound measuring the ratio of IJV/CCA cross-sectional area is a noninvasive, convenient and reliable method to evaluate the volume responsiveness of critical patients.