Use of bedside ultrasound of internal jugular vein for assessment of intravascular volume
Munie S, Kandagatla P, Blyden D, Dereczyk D, and Killu K. Use of bedside ultrasound of internal jugular vein for assessment of intravascular volume. Crit Care Med 2019; 47(1).
Crit Care Med
Learning Objectives: Intravascular volume assessment using a bedside ultrasound (BU) traditionally focuses on evaluation of inferior vena cava or heart. However, this can sometimes be difficult to perform and interpret for novice ultrasound users. This study looks at evaluating the internal jugular vein (IJV) ultrasound alone for volume assessment in comparison with standard methods (SM) and clinical impression. Methods: A Prospective, observational study in the surgical intensive care unit of a single academic tertiary center was performed. Patients who underwent BU evaluation of their IJV for volume status evaluation while laying at 30 degree inclination and who had standard invasive and non-invasive volume assessment monitors were included in this study. Volume status score looking at IJV was developed (Hypovolemia: >40% respiratory variation (RV) of IJV = Score of -1; Euvolemia: 20-40% RV of IJV = Score of 0; Hypervolemia: <20% RV of IJV = Score of +1). Volume assessment by SM included: heart rate, mean arterial pressure, central venous pressure, serum lactate, Oxygen Saturation of central venous blood (SCVO2), and cardiac index. Correlation between IJV measurements and SM measurements was evaluated by deriving the Spearman's correlation coefficient. A receiver operating characteristic analysis was used to assess the ability of the IJV score to detect hypovolemia. Results: Sixty one patients included in the study. Thirty seven (61%) were male, 39 (64%) were Caucasian and mean age was 59 years ± 14. BU of IJV was able to classify volume status into the three groups of hypovolemia (score -1), euvolemia (score 0) and hypervolemia (score +1), with a strong correlation to standard measures, r=0.90, p<0.001. IJV ultrasound was very strong at discriminating between hypovolemic and non-hypovolemic patients, AUC 0.94 (95% CI: 0.93-1.0), p<0.001 with a 90.5% sensitivity and 92.5% specificity in determining hypovolemia. Conclusions: Volume status assessment by BU of IJV can be used to classify patients using a score as hypovolemic (-1), euvolemic (0) and hypervolemic (+1) which was found to strongly correlate with SM of volume assessment.