Renal-dose dopamine postcardiac surgery in patients with acute kidney injury

Background: Many studies have investigated the prophylactic use of dopamine in cardiac or critically ill patients with controversial results. However, only very few studies investigated the therapeutic use of low-dose dopamine in cardiac surgery patients after the development of acute kidney injury (AKI). Therefore, the aim of our study was to investigate the effect of postoperative use of low-dose dopamine in patients who develop AKI postcardiac surgery on improvement in renal function. Methods: This is a retrospective cohort study that included all adult patients who underwent cardiac surgery with the use of cardiopulmonary bypass and developed AKI between January 2017 and December 2020. Ninety-six patients were enrolled in the study and were divided into two groups; the first group who did not receive postoperative renal-dose dopamine (39 patients) and the second group who received dopamine (57 patients). The outcomes of interest were the improvement in renal function as indicated by the serum creatinine level, the requirement for dialysis, and the 30-day mortality. Results: The dopamine group had higher postoperative peak creatinine levels (205 vs. 164, P < 0.001) and higher requirements for dialysis (22.81% vs. 2.56%, P = 0.01) compared to the nondopamine group. In addition, the dopamine group had longer duration of intubation (24 h vs. 21 h, P = 0.01), longer requirement for inotropic support (4 days vs. 3 days, P < 0.001), and higher rate of re-exploration for bleeding or tamponade (21.05% vs. 2.56%, P = 0.01). Multivariate regression analysis showed that time from surgery was the only factor associated with an increase in creatinine level while dopamine use was not associated with an increase or decrease in postoperative creatinine level. Conclusion: The use of low-dose dopamine was not effective as a therapeutic agent in improving renal function or eliminating the need for dialysis in patients who develop AKI postcardiac surgery