Yunie Kim

Date of Award


Document Type

Open Access Thesis

Degree Name

Medical Doctor (MD)

First Advisor

Lei Chen


Dehydration is a common pediatric condition, but limitations exist with current methods of assessing pediatric fluid status, particularly with interobserver variabilities in clinical assessment and the inaccuracy and questionable validity of laboratory tests. Bedside ultrasonography (US) measurement of the inferior vena cava (IVC) and aorta (Ao) may be useful in objectively assessing children with suspected dehydration. The objectives of this study were 1) to compare the IVC and Ao diameter (IVC/Ao) ratio of dehydrated children with euvolemic controls and 2) to compare the IVC/Ao ratio before and after intravenous (IV) rehydration in children with clinical dehydration. This prospective observational study was performed in an urban pediatric emergency department. Children between 6 months and 16 years of age with clinical evidence of dehydration and who were to receive IV fluid hydration were enrolled. Bedside US measurements of the IVC and Ao were taken pre- and post-IV fluid hydration administration. An age-, gender-, and weight-matched control was enrolled for each subject. The IVC/Ao ratios of subjects and controls were compared using the Wilcoxon signed rank test, as were the ratios before and after IV hydration for each subject. Thirty-six pairs of subjects and matched controls were enrolled. The IVC/Ao ratios in the subjects were lower as compared with controls (mean of 0.75 vs. 1.01), with a mean difference of 0.26 (95% confidence interval = 0.18 to 0.35, p < 0.001). In subjects, the IVC/Ao ratios were significantly lower before IV hydration (mean of 0.75 vs. 1.09), with a mean difference of 0.34 (95% confidence interval = 0.29 to 0.39). As measured by bedside US, the IVC/Ao ratio is lower in children clinically assessed to be dehydrated. Furthermore, it increases with administration of IV fluid boluses. The IVC/Ao ratio, as determined by bedside US, is an objective and noninvasive method of evaluating fluid status in children.


This is an Open Access Thesis.

Open Access

This Article is Open Access