**1. Introduction**

Ischemia-reperfusion (I/R) injury is a phenomenon in which cellular damage in a hypoxic organ is accentuated following the oxygen restoration [1–3], being a major pathophysiological event and cause of morbidity and mortality in liver resections and transplantation [4]. Despite the attempts to solve this problem, hepatic I/R is an unresolved problem. In addition, hepatic steatosis is a major risk factor for liver surgery, as it is associated with an increased complication index and postoperative mortality after major liver resection and transplantation, since steatotic livers show impaired regenerative response and reduced tolerance to I/R injury compared with non-steatotic ones. Of note, the prevalence of steatosis ranges from 24 to 45%

of the population and consequently a further increase in the number of steatotic livers submitted to surgery is to be expected [5]. These observations highlight the need to develop protective strategies in liver surgical conditions.

The mechanisms involved in liver I/R injury are complicated, mainly including microcirculation failure and oxidative stress [4]. A wide range of strategies has been attempted in order to mitigate I/R injury, mainly pharmacological treatments focused on gene therapy, improvement of preservation solutions, among others. However, an effective treatment is still lacking [4] since is difficult to achieve by targeting individual mechanism. Surgical strategies such as the ischemic preconditioning (IPC) technique noted for its effectiveness, as it activates several protective pathways against I/R injury in experimental models should be considered. IPC can be either applied directly to the target organ [6] or remotely (RIPC) to a distant vascular bed [7]. The benefits of the IPC and RIPC observed in experimental models of hepatic warm and cold ischemia [8, 9] prompted human trials of ischemic preconditioning. However, controversial results have been showed in the clinical practice. Therefore, the present chapter aims to describe the current knowledge of the IPC and RIPC in liver resections and liver transplantation of both steatotic and non-steatotic livers. In addition, the scientific controversies regarding the possible beneficial effects of these techniques, in experimental, translational and clinical studies in the setting of liver surgery will be discussed.
