Intravascular volume assessment by sonography (VAS) score
Killu K, Al-Jubouri M, Baldawi M, Watson J, Dereczyk D, Wenk G, Coba V, and Blyden D. Intravascular volume assessment by sonography (VAS) score. Crit Care Med 2018; 46(Suppl 1):43.
Crit Care Med
Learning Objectives: Intravascular volume Status assessment (IVSA) by bedside ultrasound (BU) usually focus on individual organs. Combining different organs and using a scoring system to compare to the standard methods (SM) and the clinical impression, may aid in the diagnosis and standardize BU applications.
Methods: A Prospective, observational study, in the surgical intensive care unit (SICU), of a single academic tertiary center. Patients with IVSA were included. IVSA identified by the SM of heart rate, mean arterial pressure, central venous pressure, serum lactate, Oxygen Saturation of central venous blood (SCVO2), and cardiac index. BU studies included the heart, lungs, Inferior Vena Cava (IVC), and Internal Jugular Vein (IJV). VAS score developed to assess IVSA; A) Heart: Hyperkinetic=-1, Normal=0, hypokinetic=+ 1. B) Lungs: Absence of B-Lines=-1, 1-2 B-Lines=0, 3 B-Lines=+1. C) IVC: < 2.5 cm and > 50% respiratory variation in diameter=-1, 1.5-2.5 cm, < 50% respiratory variation = 1, > 2.5 cm and < 50% respiratory variation = +1. D) IJV: > 40% respiratory variation =-1, 20-40% respiratory variation = 1, < 20%=+1. VAS score ranges from-4 to +4. A score near zero indicates euvolemia, a score near-4 indicates hypovolemia, and a score near +4 indicate hypervolemia. Data for SM and BU compared to each other. Comparisons were performed using the Spearman's correlation coefficient tests, the nonparametric equivalent to a paired t-test.
Results: 23 patients with IVSA included in the study. Twelve (52%) were female, 12 (57%) were White and the mean age was 55.5 years with a range from 27-90. There were no clear cut-points to divide the total scores into the three categories of hypovolemia, euvolemia and hypervolemia. There was a trend toward a zero or negative score for hypovolemia and euvolemia. The positive (> 0) total score, was significant in the VAS score hypervolemia compared to SM (correlation coefficient=0.51, p = 0.013). Overall there was a significant association between the VAS score using BU and the clinical impression of volume status (correlation coefficient= 0.51, p = 0.013).
Conclusions: VAS score using BU correlates with the clinical impression of volume status measurements. This can help standardize and aid in the diagnosis of volume status during BU.