Ischaemic Preconditioning Protects Against Ischaemia/Reperfusion Injury: Emerging Concepts

IP utilises endogenous mechanisms in skeletal muscle, liver, lung, kidney, intestine and brain in animal models to convey varying degrees of protection from I/R injury. To date there are few human studies, but recent reports suggest that human liver, lung and skeletal muscle acquire similar protection after IP. Specifically, preconditioned tissues exhibit reduced energy requirements, altered energy metabolism, better electrolyte homeostasis and genetic re-organisation, giving rise to the concept of 'ischaemia tolerance'. IP also induces 'reperfusion tolerance' with less reactive oxygen species and activated neutrophils released, reduced apoptosis and better microcirculatory perfusion compared to non-preconditioned tissue. Systemic I/R injury is also diminished by preconditioning. IP is ubiquitous but more research is required to fully translate these findings to the clinical arena.