Intra-operative hemodynamic management in high-risk surgery is a priority for the anesthesiologist. The current strategy is based on the continuous measurement of cardiac output and its maximization by vascular filling has many limitations: invasiveness, measurement difficulties, impaired performance, imperative surgical restriction of filling, lack of evaluation of flow rate and metabolic needs. Biomarkers may be able to detect early an inadequacy between cardiac output and tissue oxygen requirements, venous saturation with oxygen (ScvO2) and arteriovenous difference in partial pressure of carbon dioxide (ΔPCO2) as well as the appearance of cellular hypoxia (lactate and arteriovenous difference in partial pressure of carbon dioxide/arteriovenous difference in oxygen) (ΔPCO2) / DAVO2). Moreover, the medical literature remains poor on the evaluation of these markers in per-operative context all the more for ΔPCO2 and ΔPCO2 / DAVO2. It seems interesting to evaluate the potential of these tools, in patients with major surgery and at high risk (major hepatectomy, oesophagectomy and duodeno-pancreatectomy), to predict the risk of postoperative complications, especially since surgery involves a restrictive vascular filling strategy that may be potentially deleterious to the patient.

Inclusion Criteria:

Major patient

Patient eligible for a high risk scheduled gastrointestinal surgery from:

• Esophagectomy
• Major hepatectomy (≥ 3 segments)
• Cephalic duodeno-pancreatectomy Patient with an arterial catheter and a central venous line in superior vena cava.

Patient hospitalized post-operatively in intensive care unit as agreed in consultation with preoperative anesthesia.

Exclusion Criteria:

• Pregnant or lactating patients
• Patient with an unstable acute condition at the time of surgery (acute heart, respiratory or renal failure, severe sepsis or septic shock, hemorrhagic shock)
• Patient opposing his participation in the study
• Patient protected by law (guardianship)
• Patient deprived of liberty
• Patient with a contraindication to the establishment of a central venous route in superior vena cava territory or a radial or femoral arterial catheter

The study concerns patients operated for a high-risk digestive surgery, hospitalized postoperatively in intensive care unit (agreed in anesthesia consultation). These patients will also need to have an arterial catheter and a central venous line in the superior vena cava