Is there any difference between blood and crystalloid cardioplegia for myocardial protection during cardiac surgery? A meta-analysis of 5576 patients from 36 randomized trials

Objective:To compare the efficacy of blood versus crystalloid cardioplegia for myocardial protection in patients undergoing cardiac surgery.Methods:MEDLINE, EMBASE, CENTRAL/CCTR, SciELO, LILACS, Google Scholar and reference lists of relevant articles were searched for clinical studies that reported in-hospital outcomes after blood or crystalloid cardioplegia for myocardial protection during cardiac surgery procedures from 1966 to 2011. The principal summary measures were risk ratio (RR) for blood compared to crystalloid cardioplegia with 95% Confidence Interval (CI) and P values (considered statistically significant when <0.05). The RRs were combined across studies using the DerSimonian-Laird random effects model and fixed effects model using the Mantel-Haenszel model - both models were weighted. The meta-analysis was completed using the software Comprehensive Meta-Analysis version 2 (Biostat Inc., Englewood, New Jersey).Results:Thirty-six studies (randomized trials) were identified and included a total o...