The caval index: an adequate non-invasive ultrasound parameter to predict fluid responsiveness in the emergency department?

Background: Fluid therapy is the first important step in patients with signs of shock but assessment of the volume status is difficult and invasive measurements are not readily available in the emergency department. We have investigated whether the respiratory variation in diameter of the inferior vena cava is a reliable parameter to predict fluid responsiveness in spontaneous breathing emergency department patients with signs of shock.

Methods: All patients admitted to the emergency department during a 15 week period were screened for signs of shock.