Effects of early renal replacement therapy on the outcomes of critically ill patients with acute kidney injury: A systematic review and meta-analysis

Background: This meta-analysis aimed to evaluate the efficacy of early renal replacement therapy (RRT) in critically ill patients with acute kidney injury (AKI). Methods: Keywords included early initiation, AKI, and RRT. The inclusion criteria were based on the population, intervention, comparator, outcomes, and study designs. An electronic search was conducted, and the following databases were used: PubMed, EMBASE, Cochrane Library, Web of Science, CINAHL, and ClinicalTrials.gov. The primary outcome was 28-day mortality. Results: Twenty six studies were eligible for this meta-analysis. The pooled 28-day mortality in 25 studies was 44.7% (1770/3956) and 47.8% (1851/3875) in early and late RRT groups, respectively, and a significant difference was observed between groups (risk ratios [RR] = 0.81; 95% confidence intervals [CI] = 0.72–0.91; I 2 = 73%). No significant difference was observed in RRT dependence rate (RR = 1.21; 95% CI = 0.99–1.49; I 2 = 28%), recovery of renal function (RR = 1.35; 95% CI = 0.99–1.84; I 2 = 91%), and duration of RRT (standard error of the mean = 0.23; 95% CI = −0.94–1.40; I 2 = 99%). Subgroup analyses showed that early RRT was associated with lower mortality in surgical patients (RR = 0.60; 95% CI = 0.44–0.80; I 2 = 74%) and in single-center settings (RR = 0.64; 95% CI = 0.52–0.79; I 2 = 64%). Conclusions: For critically ill patients with AKI, early initiation of RRT can reduce 28-day mortality by 19% (relative risk reduction of 19%, absolute risk reduction of 3.1%) compared to late initiation, a statistically significant difference. However, clinicians should be alert to the possible adverse effect such as hypotension, catheter-related infection, and hypophosphatemia of early RRT.