Ischaemic preconditioning for liver transplantation.

BACKGROUND: Ischaemic preconditioning is a mechanism for reducing organ ischaemia reperfusion injury by a brief period of organ ischaemia.
OBJECTIVES: To assess the advantages and disadvantages of ischaemic preconditioning during donor hepatectomy for liver transplant recipients. SEARCH STRATEGY: We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until March 2007. SELECTION CRITERIA: We included only randomised clinical trials comparing ischaemic preconditioning versus no ischaemic preconditioning during donor liver retrievals performed in humans in this review (irrespective of language or publication status). DATA COLLECTION AND ANALYSIS: We collected the data on the characteristics of the trial, methodological quality of the trials, mortality, initial poor function, primary graft non-function, re-transplantation, liver function tests, markers of neutrophil activation, apoptosis, and intensive therapy unit stay. We analysed the data with both the fixed-effect and the random-effects models. For each binary outcome we calculated the odds ratio (OR) with 95% confidence intervals (CI) based on intention-to-treat analysis. For continuous outcomes, we calculated the weighted mean difference (WMD) with 95% CI. MAIN
RESULTS: In three trials, 162 cadaveric liver donor retrievals were randomised; 78 to ischaemic preconditioning and 84 to no ischaemic preconditioning. In one trial, 15 living donor liver retrievals were randomised; 10 to ischaemic preconditioning and 5 to no ischaemic preconditioning. Three of the four trials were of low-risk bias. There was no statistically significant difference in mortality, initial poor function, primary graft non-function, or re-transplant. There was no statistically significant difference in the transaminase activity, bilirubin level, prothrombin activity, median myeloperoxidase activity, median cluster of differentiation eight (CD8) expression, median inducible nitrogen oxide synthetase, or apoptosis. There was also no significant difference in the median intensive therapy unit stay of the recipients. AUTHORS'
CONCLUSIONS: 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. Further randomised clinical trials are necessary to evaluate the role of ischaemic preconditioning in donor liver retrievals involving a period of warm reperfusion, following ischaemic preconditioning during donor liver retrieval.