Passive leg raising for assessment of volume responsiveness: a review

To evaluate the existing evidence on the passive leg raising (PLR) test for fluid responsiveness prediction.

It has been well established that either insufficient or excessive fluid administration derives in worse outcomes in critically ill patients, highlighting that a more accurate assessment of fluid management is required. Accordingly, several cardiovascular indices have been tested to improve our ability to predict patients' response to fluid loading at the bedside, the so-called functional hemodynamic monitoring. The standardized PLR is a relatively novel maneuver that, over the past 10 years, has repeatedly demonstrated high sensitivity and specificity for fluid responsiveness prediction.

The current review underlines that PLR is an easy-to-perform and reliable method to assess fluid responsiveness. Its excellent performance is maintained even in many situations in which other dynamic predictive indices are not consistent and represents a valid alternative to the fluid challenge to avoid unnecessary volume administration.