The story concerning non-invasive fluid responsiveness monitoring is not new. From many years, clinicians observed that plethysmographic waveform is generally different in patients responding to fluid therapy. Consequently, when the study of Michard et al. popularized the use of dynamic parameters for the prediction of fluid responsiveness, a great hope appeared to improve fluid management during the perioperative period.  Automated calculation of the plethysmographic respiratory variation with the pleth variability index (PVI), from Masimo Co, permitted to introduce the concept of continuous, non-invasive, optimization of dynamic parameters in high as in low risk patients.  Indeed, we confirmed that it possible and fruitful in randomized trials in major abdominal surgery.