Systematic review and <i>meta</i>-analysis of prophylaxis use with intravenous contrast exposure to prevent contrast-induced nephropathy

Purpose: Iodinated radiographic contrast media has been associated with an acute deterioration in renal function, termed contrast induced nephropathy (CIN). This review aims to establish the efficacy of prophylaxis interventions used in adult patients prior to intravenous exposure to iodinated contrast to reduce the risk of CIN.Methods: An electronic search for published peer-reviewed articles was performed, supplemented with manual review of references from previous systematic reviews and the National Institute for Health and Care Excellence guidelines. Risk of bias was assessed using the Cochrane Collaboration’s tool for assessing risk of bias. Random-effect meta-analyses were used to assess CIN incidence, need for kidney replacement therapy (KRT), mortality, fluid overload and persistent kidney dysfunction.Results: 22 studies assessing a range of interventions were included in the qualitative analysis. The incidence of CIN was reduced by the use of N-acetylcysteine compared to a control group of saline (risk difference = -0.07, 95% CI -0.13 to -0.01) but not by sodium bicarbonate compared to control group of saline (risk difference = -0.02, 95% CI -0.04 to 0.01). Published studies give no indication that prophylactic interventions have significant impact on the need for KRT, mortality or persistent renal impairment.Conclusion: Evidence for prophylaxis against CIN in patients receiving intravenous iodinated contrast is limited. There was an association with the use of NAC with reduced incidence of CIN following intravenous contrast but there was no impact on other clinical outcomes assessed. The clinical significance of these findings remains unclear and further research focusing on these clinical outcomes is required