Ultrasound assessment of the inferior vena cava for fluid responsiveness: easy, fun, but unlikely to be helpful

摘要

For medical disciplines responsible for the care of severely ill patients, arguably nothing is more desperately needed than a practical and accurate tool to predict fluid responsiveness (FR). Defined as the physiologic state where the administration of an intravenous fluid bolus will cause an increase in stroke volume, it is crucial to understand FR for four reasons:1) Intravenous fluids are, appropriately, the mainstay of early resuscitation because of their availability, low cost, ease of administration, and potential to improve oxygen delivery; 2) After the very initial stages of resuscitation, critically ill patients consistently have a near 50% probability of being in an FR state, indicating that clinicians are typically operating in a zone of perfect uncertainty; 3) Inadequate fluid administration is generally felt to be harmful; 4) Overzealous fluid administration is associated with increased mortality.