Echocardiographic Assessment of Volume Variation Secondary to Preoperative Fasting

Inclusion Criteria: * The patient must have given his/her informed and signed consent * The patient must be insured or beneficiary of a health insurance plan * The patient is ASA (American Society of Anesthesiologists) class I, II or III * The patient has not been fasting for more than 6 hours at the time of inclusion * The patient is schelduled for a gynecological or visceral surgery Exclusion Criteria: * The patient is participating in another study * The patient is in an exclusion period determined by a previous study * The patient is under judicial protection, under tutorship or curatorship * The patient refuses to sign the consent * It is impossible to correctly inform the patient * The patient is pregnant * The patient is breastfeeding * The patient is ASA class IV * The patient has insulin dependent diabetes * The patient has a cardiac or respiratory dysfunction * The patient has a heart rhythm disorder * The patient has renal insufficiency with dialysis * The patient is being treated with diuretics * The patient has had a bowel preparation * Emergency surgery * Outpatient surgery