Sonographic measurement of the inferior vena cava as a marker of blood loss

Our data indicates that the measurement of the IVC diameter is a reliable indicator of blood loss, even in small amounts of 450 mL. On average, there was about a 5-mm decrease in both the IVCe and IVCi after donation of 450 mL of blood. The measurement of the IVCe may be an important addition to the ultrasonographic evaluation of trauma and other potentially volume-depleted patients.