No evidence to support or refute the use of ischaemic preconditioning in liver transplantation

Ischaemic preconditioning is a mechanism for reducing organ ischaemia reperfusion injury by a brief period of organ ischaemia, ie, decrease the injury caused by return of blood supply to the organ after a period of decreased or absent blood supply by exposing the organ to shorter periods of decreased blood supply. There is considerable controversy regarding whether ischaemic preconditioning during donor liver retrieval has beneficial effect on the outcome of liver transplantation. This systematic review includes five randomised clinical trials assessing the advantages and disadvantages of ischaemic preconditioning during donor hepatectomy for liver transplant recipients. In four trials, 270 cadaveric liver donor retrievals were randomised; 131 to ischaemic preconditioning and 139 to no ischaemic preconditioning; and in one trial, 15 living donor liver retrievals were randomised; 10 to ischaemic preconditioning and 5 to no ischaemic preconditioning. All the trials were high bias-risk trials. There was no statistically significant difference in mortality, initial poor function, re-transplant, primary graft non-function, or in any other outcome other than enzyme markers of liver injury, which was in different directions in different trials. There is currently no evidence to support or refute the use of ischaemic preconditioning in donor liver retrievals. Further studies are necessary to identify the optimal ischaemic preconditioning stimulus.