Ultrasound Guided Volume Assessment Using Inferior Vena Cava Diameter

Ultrasound provides a rapid method of evaluating the emergency patient at the bedside by the treating physi- cian. Besides being advantageous in eliminating or supporting a differential diagnosis in an emergency patient, bedside ul- trasound can also rapidly evaluate physiology. This articles describes such a use of bedside ultrasound, the evaluation of the inferior vena cava size and collapsibility in the evaluation of shock states. The ultrasound procedure is described as well as how to integrate the information gained from this test into clinical practice. treatment or pneumonia as a result of immunosuppression due to AIDS. Since the treatment for volume overload and pneumonia is very different, a bedside ultrasound exam was performed to assist in distinguishing the two diagnoses. A bedside limited ECHO showed a small pericardial effusion and global hypokinesis. More revealing, visualization of the IVC showed a small vessel that collapsed completely with inspiration, which is consistent with a low central venous pressure and not consistent with volume overload. The pa- tient was diagnosed with pneumonia, treated with appropri- ate antibiotics, and hemodialysis was performed after admis- sion to the hospital.