Fenoldopam for preventing and treating acute kidney injury

Fenoldopam is a short-acting benzazepine selective dopaminergic A1 (DA1) receptor agonist with increased activity at the D1 receptor compared with dopamine. Activation of the DA1 receptors increases kidney blood flow because of dilatation of the afferent and efferent arterioles. Previous reviews have been published on the efficacy and safety of fenoldopam for acute kidney injury (AKI); however, they either combined data on its effect on both prevention and treatment of AKI, focused on only those undergoing cardiac surgery and/or excluded children.

This review aimed to assess the benefits and harms of fenoldopam for the prevention or treatment of AKI in children and adults.

We searched the Cochrane Kidney and Transplant Register of Studies up to 12 November 2024 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register were identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal and ClinicalTrials.gov.

We included randomised controlled trials (RCTs) evaluating fenoldopam for the prevention or treatment of AKI in children and adults following surgery, radiocontrast exposure or sepsis.

Two authors independently assessed studies for eligibility, assessed the studies for risk of bias and extracted data from the studies. Dichotomous outcomes were presented as relative risk (RR) with 95% confidence intervals (CI). For continuous outcomes, the mean difference (MD) with 95% CI was used. Statistical analysis was performed using the random-effects model. We assessed the certainty of the evidence using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach.

We identified 25 RCTs, including 3339 randomised participants. Twenty-three studies used fenoldopam for preventing AKI and two for the treatment of AKI. Nine studies included participants undergoing cardiac surgery, and one included children. The risks of bias for sequence generation and concealment were low in 11 and 13 studies, respectively. Only 13 and 18 studies were at low risk of performance bias and detection bias, respectively. The risk of attrition bias and selective reporting were judged to be at low risk of bias in 17 and 10 studies, respectively. We included data in the meta-analyses from eight of the 14 studies comparing fenoldopam with placebo or saline, all six studies comparing fenoldopam with dopamine, all five studies comparing fenoldopam with N-acetylcysteine (NAC) for the prevention of AKI and from the two studies comparing fenoldopam with placebo or saline for the treatment of AKI. Compared with placebo or saline fenoldopam probably results in fewer participants developing AKI (RR 0.72, 95% CI 0.53 to 0.98; 8 studies, 1147 participants; I² = 48%; moderate certainty) but may make little or no difference to the number requiring kidney replacement therapy (KRT) (RR 0.81, 95% CI 0.31 to 2.15; 7 studies, 835 participants; I² = 17%), risk of death (RR 0.76, 95% CI: 0.58 to 1.00; 7 studies, 944 participants; I² = 0%) or change in urine output (SMD 0.20, 95% CI -0.44 to 0.84; 2 studies, 58 participants; I² = 34%; all low certainty). Fenoldopam may result in a shorter stay in the ICU (MD -1.81 days; 95% CI -2.41 to -1.21; 4 studies, 403 participants; I² = 0%). It is uncertain whether adverse events (hypotension, myocardial infarction, drug intolerance, cardiac arrhythmias) differed between the treatment groups as the certainty of the evidence was very low. In patients undergoing cardiac surgery, fenoldopam, compared to placebo or saline, may make little or no difference to the prevention of AKI, the need for KRT or death. Compared with dopamine, fenoldopam may make little or no difference to the prevention of AKI (RR 0.62, 95% CI 0.23 to 1.68; 4 studies, 398 participants; I² = 78%), the number requiring KRT (RR 0.74, 95% CI 0.29 to 1.87; 4 studies, 434 participants; I² = 0%) or the risk of death (RR 1.27, 95% CI 0.36 to 4.50; 2 studies, 174 participants; I² = 0%) (all low certainty). It is uncertain whether participants receiving fenoldopam were more likely to develop hypotension compared with those receiving dopamine (RR 3.00, 95% CI 1.06 to 8.52; 1 study, 80 participants; very low certainty). Change in urine output was not reported. It is uncertain whether fenoldopam compared with NAC prevents AKI (RR 1.68, 95% CI 0.79 to 3.56; 3 studies, 359 participants; I² = 38%), reduces the need for KRT (RR 0.96, 95% CI 0.15 to 6.26; 2 studies, 137 participants; I² = 0%), or the risk of death (RR 1.05, 95% CI 0.07 to 15.66; 1 study, 39 participants) (all very low certainty). It is uncertain whether hypotension was more frequent with fenoldopam (RR 5.10, 95% CI 0.25, 104.94; 1 study, 192 participants; very low certainty). Change in urine output was not reported. In participants with established AKI, it is uncertain whether fenoldopam compared to placebo or half saline reduces the numbers needing KRT (RR: 0.91, 95% CI 0.54 to 1.54; 2 studies, 822 participants; I² = 58%; very low certainty) or the risk of death (RR 0.81, 95% CI 0.44 to 1.48; 2 studies, 822 participants; I² = 66%; very low certainty), or if it increases the risk of hypotension (RR 1.65, 95% CI 1.22 to 2.22; 2 studies, 822 participants; I² = 0%; very low certainty).

Fenoldopam administration in patients at risk of AKI is probably associated with a lower risk of developing AKI and shorter ICU stay when compared with placebo or saline, but has little or no effect on the need for KRT or the risk of death. In those undergoing cardiac surgery, fenoldopam may not confer any benefits compared with placebo or saline. Furthermore, it remains unclear whether fenoldopam is more or less effective than either dopamine or NAC in reducing the risk for AKI or the need for KRT. Further well-designed and adequately powered studies are required to evaluate the efficacy and safety of fenoldopam in preventing or treating AKI.