Fenoldopam use during Cardiopulmonary Bypass and Postoperative Rates of Acute Kidney Injury

Acute kidney injury (AKI) is a complication following heart surgery that is associated with increased morbidity and mortality. Fenoldopam is a dopaminergic receptor agonist that has been successful in the prevention of cardiac surgery-associated AKI. We hypothesized that fenoldopam started preoperatively would reduce the risk of AKI in patients with chronic kidney disease (CKD), stage 3 or higher.

We conducted a retrospective study of adult patients admitted from 2015 to 2019 for cardiac surgery requiring cardiopulmonary bypass (CPB). Fenoldopam was started in the operating room 1 to 2 hours before the procedure and continued for up to 16 hours post-CPB at a rate of 0.3 mcg/kg/min. The primary outcome was the incidence of postoperative AKI with or without fenoldopam.

A total of 203 patients with CKD stage 3 or higher were examined in this study, 35.5% of whom received fenoldopam. Of the patients who received fenoldopam, 41.67% developed AKI compared to 38.17% of those without fenoldopam. Being female had a small protective effect against AKI (OR 0.233, CI 0.108-0.502), as did having an adequate hematocrit level prior to surgery (OR 0.921, CI 0.871-0.974). Analysis revealed that a hematocrit level of 37.18% indicated anemia in the study population.

While the administration of fenoldopam prior to CPB in patients with CKD stage 3 or higher did not significantly reduce AKI after cardiac surgery or significantly reduce length of stay, possible renal protective properties were identified. Being female and having an adequate preoperative hematocrit level were identified as possible investigative points for future studies.