title: Remote ischemic conditioning for kidney protection: A meta-analysis.
abstract: Results from randomized controlled trials (RCTs) concerning kidney effect of remote ischemic conditioning (RIC) are inconsistent.
  
  
  
  We searched for relevant studies in Medline, Embase, the Cochrane Library, Google Scholar and Chinese database (SinoMed), as well as relevant references from their inception to November 2015. We performed a systematic review and meta-analysis of all eligible RCTs of RIC with kidney events.
  
  
  
  We included 37 RCTs from 2007 to 2015 involving 8168 patients. Pooled analyses of all RCTs showed RIC significantly reduced the incidence of investigator-defined acute kidney injury (AKI) compared with control groups (RR 0.84, 95% CI 0.73-0.96, P = .009) (I(2) = 25%). However, the difference was not significant when only RIFLE (Risk, Injury, Failure, Loss, End Stage), AKIN (Acute Kidney Injury Network), or KDIGO (Kidney Disease Improving Global Outcomes) criteria were applied to the definition of AKI (RR 0.87, 95% CI 0.74-1.02, P = .08) (I(2) = 22%). In subgroup analysis, RIC showed a significant benefit on reducing investigator-defined AKI in patients following percutaneous coronary intervention (RR 0.64, 95% CI 0.46-0.87), but not after cardiac surgery (RR 0.93, 95% CI 0.82-1.06). There was no difference for changes in the incidence of renal replacement therapy, estimated glomerular filtration rate or serum creatinine.
  
  
  
  RIC might be beneficial for the prevention of investigator-defined AKI; however, the effect is likely small. Moreover, due to lack of an effect on use of renal replacement therapy, estimated glomerular filtration rate, RIFLE, AKIN, or KDIGO-defined AKI, and serum creatinine, the evidence for RIC is not robust. Finally, recent large-scale RCTs of RIC focusing on patient-centered outcomes do not support the wider application of RIC.
authors.affiliation: Department of Nephrology, West China Hospital of Sichuan University, Sichuan, Chengdu, China; Department of Intensive Care Unit, Austin Hospital, 145 Studley Road, Heidelberg, VIC 3084, Australia.
authors.forename: Ling
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Nephrology, West China Hospital of Sichuan University, Sichuan, Chengdu, China.
authors.forename: Yongshu
authors.initials: Y
authors.lastname: Diao
authors.affiliation: Department of Anesthesiology, Austin Hospital, 145 Studley Road, Heidelberg, VIC 3084, Australia.
authors.forename: Guangjun
authors.initials: G
authors.lastname: Chen
authors.affiliation: Department of Intensive Care Unit, Austin Hospital, 145 Studley Road, Heidelberg, VIC 3084, Australia.
authors.forename: Aiko
authors.initials: A
authors.lastname: Tanaka
authors.affiliation: Department of Intensive Care Unit, Austin Hospital, 145 Studley Road, Heidelberg, VIC 3084, Australia; Australian and New Zealand Intensive Care Research Centre, Melbourne, VIC, Australia.
authors.forename: Glenn M
authors.initials: GM
authors.lastname: Eastwood
authors.affiliation: Department of Intensive Care Unit, Austin Hospital, 145 Studley Road, Heidelberg, VIC 3084, Australia; Australian and New Zealand Intensive Care Research Centre, Melbourne, VIC, Australia. Electronic address: rinaldo.bellomo@austin.org.au.
authors.forename: Rinaldo
authors.initials: R
authors.lastname: Bellomo
mesh_terms: D058186:Acute Kidney Injury / Q000517:prevention & control*; D003422:Critical Care; D006801:Humans; D019194:Ischemic Preconditioning; D007677:Kidney Function Tests; D062645:Percutaneous Coronary Intervention
keywords: Acute kidney injury; Kidney; Meta-analysis; Remote ischemic preconditioning; Renal replacement therapy