Pharmacological strategies for the prevention of acute kidney injury following cardiac surgery: an overview of systematic reviews

CONTEXT: Post cardiac surgery acute kidney injury (AKI) is common, poorly understood and associated with a significant increase in morbidity and mortality.

OBJECTIVES: An overview of systematic reviews that have evaluated pharmacological agents for the prevention of AKI post cardiac surgery.

DATA SOURCES: We searched electronic databases (PubMed and the Cochrane Database of Systematic Reviews) from inception to January 2014.

STUDY SELECTION: Systematic reviews of randomized controlled trials that have evaluated pharmacological agents for the prevention of AKI in adult patients undergoing cardiac surgery.

DATA ANALYSIS: Numbers needed to treat (NNT) or harm (NNH) were calculated from pooled events given in each meta-analysis. Primary outcome measures were defined as (i) mortality, (ii) need for renal replacement therapy (RRT), and (iii) acute kidney injury.

RESULTS: Data from 7 systematic reviews evaluating 6 different pharmacological renoprotective agents were included. Dopamine, fenoldopam and N-acetylcysteine did not demonstrate any benefit in terms of mortality, need for RRT or incidence of AKI. Atrial natriuretic peptide reduced the need for RRT (NNT = 22 (95% CI: 13 to 73) and brain natriuretic peptide reduced the incidence of AKI (NNT = 11 (95% CI: 6 to 32), although both agents did not demonstrate any effect on mortality. Loop diuretics demonstrated increased incidence of AKI (NNH = 8 (95% CI: 5 to 15).

CONCLUSION: There is a paucity of effective renoprotective agents that can be used in adult cardiac surgical patients. There is an urgent need to develop novel renoprotective strategies.