Efficacy and safety of N-acetylcysteine for preventing post-intravenous contrast acute kidney injury in patients with kidney impairment: a systematic review and meta-analysis.

Abstract

N-Acetylcysteine (NAC) may confer protection against post-contrast acute kidney injury (PC-AKI), although evidence is sparse and conflicting. The objective was to analyse the evidence on the efficacy and safety of NAC vs no administration of NAC in preventing PC-AKI in patients with pre-existing kidney impairment undergoing a non-interventional radiological examination requiring intravenous (IV) contrast media (CM) administration. We carried out a systematic review including randomised controlled trials (RCTs) published in MEDLINE, EMBASE, and Clinicaltrials.gov up to May 2022. The primary outcome was PC-AKI. Secondary outcomes included the requirement of renal replacement therapy, all-cause mortality, serious adverse events, and length of hospital stay. We conducted the meta-analyses using the Mantel-Haenszel method and following a random-effects model. NAC was not associated with a significant reduction in PC-AKI (RR 0.47, 95%CI 0.20 to 1.11; 8 studies; 545 participants; I2: 56%; low certainty), all-cause mortality (RR 0.67, 95%CI 0.29 to 1.54; 2 studies; 129 participants; very low certainty), or length of hospital stay (mean difference 9.2days, 95%CI - 20.08 to 38.48; 1 study; 42 participants; very low certainty). The impact on other outcomes could not be determined. NAC may not reduce the risk of PC-AKI or all-cause mortality in people with kidney impairment who receive an IV CM prior to radiological imaging, although the certainty of the evidence is very low or low. Our review concludes that prophylactic administration of N-acetylcysteine may not significantly reduce the risk of acute kidney injury in patients with kidney impairment receiving an intravenous contrast media prior to non-interventional radiological imaging, which may support decision making in this common clinical scenario. • N-Acetylcysteine may not significantly reduce the risk of acute kidney injury in patients with kidney impairment receiving an intravenous contrast media prior to non-interventional radiological imaging. • All-cause mortality and length of hospital stay would not be decreased with the administration of N-Acetylcysteine in this setting.