1. Department of anaesthesia reanimation, CHU Liège, domaine du Sart Tilman, University of Liège, Liège, Belgium;
2. Service of digestive surgery, CHU Liège, domaine du Sart Tilman, University of Liège, Liège, Belgium;
3. GRACE (Groupe francophone de Réhabilitation Après ChirurgiE), Baumont, France