Inclusion Criteria:  Major patients (≥ 18 years ) Eligible for an interventional radiology procedure or surgery under general anesthesia Monitoring of invasive blood pressure and cardiac output by trans-esophageal Doppler. Patients informed and having expressed their non-opposition to participation in this research  Exclusion Criteria:  Patients under 18 years old Atrial fibrillation Contraindication to trans-esophageal doppler Patient opposed to protocol participation Pregnant woman Patient under judicial protection Patient without affiliation to a social security scheme