Fluid Administration Limited by Lung Ultrasonography in the Operating Room: Correlation to Stroke Volume Variation (ORFALU)

The possibility of exploring the lungs by lung ultrasound, a non-invasive tool, is becoming increasingly popular for anesthesiologists. Recently, Lichtenstein has described the FALLS protocol (Fluid Administration Limited by Lung Sonography) which uses the potential of pulmonary ultrasound to evaluate early pulmonary overload due to fluid administration at a subclinical stage. Indeed, fluid administration can generate a sub-clinical interstitial syndrome that can be detected by passing from a profile A to a profile B in lung ultrasound. The transition from a profile A to a profile B therefore corresponds to the transition from a state of preload dependent to a state of preload independence. However, this tool has not been studied in the operating room. The main objective of this study will be to study the correlation between pulmonary ultrasound and SV variation measured by esophageal Doppler during fluid administration in patients with haemodynamic optimisation in the operating room during digestive, urological, gynecological and orthopedic surgeries. The main expected result is the following: good correlation between the absence of increased SV in the esophageal Doppler and the appearance of a B-profile lung ultrasound fluid administration in the operating room.