Comparison of subclavian vein and inferior vena cava collapsibility index in the intensive care unit.

Objective: The aim of this study was to evaluate the correlation between changes in the inferior vena cava collapsibility index and subclavian vein collapsibility index in patients undergoing passive leg raising tests in the intensive care unit, considering that respiratory changes affecting the inferior vena cava may similarly affect the subclavian vein.

Methods: This single-center observational study was conducted on patients aged between 18 and 85 years who underwent passive leg raising in the intensive care unit. When the patient was 45° above the bed, the inferior vena cava and subclavian vein were displayed using ultrasonography; subclavian vein collapsibility index and inferior vena cava collapsibility index values were calculated.