Recently, anesthesiologists mainly focused on Enhanced Recovery after Surgery (ERAS) and Perioperative Surgical Home (PSH) with the purpose of reduced hospital morbidity and mortality.As we known, critically ill patients often have high hospital morbidity and mortality.The microcirculation regulates the supply of oxygen and nutrients to tissues.It is increasingly believed that acute microvascular alterations may be involved in the development of organ dysfunction and mortality in critically ill patients.However, little is known about the perioperative microcirculatory effects of different anesthetics in critically ill patients.The sublingual region is frequently used as a window to microcirculation in critically ill patients.Recently, we have investigated the effects of different anesthetics (propofol, sevoflurane,desflurane) on sublingual microvascular alterations in critically ill patients, as well as observed the organ function and mortality.Perioperative microcirculatory alterations were evaluated in the sublingual mucosa using Sidestream Dark Field (SDF) imaging.Perfused vessel density (PVD), vessel perfusion [microvascular flow index (MFI)] and flow heterogeneity [heterogeneity index (HI)] were analyzed.The main objectives were to evaluate perioperative microcirculatory alterations in this setting, and whether the changes in microcirculatory parameters are associated with post-operative morbidity and/or with changes in parameters reflecting oxygen delivery.We found that different anesthetics have different effects on perioperative microvascular alterations in critically ill patients.