Detecting Relative Changes in Circulating Blood Volume using Ultrasound and Simulation

Portable ultrasound is increasingly used to assess jugular venous pressure (JVP) to approximate volume status in patients with congestive heart failure (CHF). Traditionally, increases in jugular venous pressure height signify increasing circulating blood volume. Emerging evidence, suggests that JVP correlates well with sonographic images of the internal jugular vein (IJV). This paper represents a preliminary investigation on the ability of cross-sectional area (CSA) of the IJV to measure relative changes in circulating blood volume. Fourteen healthy subjects had serial transverse ultrasound videos of their IJV captured while lying at five angles designed to simulate relative changes in blood volume. Ultrasound videos of the IJV were both manually and semi-automatically segmented, the CSA was measured, outliers were detected and removed, and Rotation Forest classifier was used to classify the data. By limiting the number of classes from five to three and removing outliers the accuracies improved from 59.50% to 91.05% and 62.74% to 91.89% for manual and semi-automatic segmentation, respectively. This pilot demonstrated that serial measurement of the CSA of the IJV in combination with machine learning techniques represents a viable opportunity to monitor changes in circulating blood volume in healthy subjects, setting the stage for a trial monitoring of patients with CHF.