Point of care ultrasound of the IVC (inferior vena cava) is a non-invasive means of volume assessment in the critically ill.  While no one study has been able to quantify exactly where to measure or make the assessment, the IVC can be assessed in a fat or flat paradigm.

In the video below, ultrasound educator Chris Eddy uses the Clarius portable ultrasound scanner to assess the IVC for volume status.

He examines the walls of the IVC to ensure that they move during respiration and are not coming in contact with each other (which could be indicative of a flat IVC). He also looks for any respiratory motion which tends to dissipate in a volume overload status.