Objective

Acute kidney injury (AKI) affects approximately 30% of patients undergoing cardiac surgery with conventional non-pulsatile cardiopulmonary bypass (CPB). Pulsatile flow has long been proposed for mitigating this complication. While the 2019 EACTS guidelines recommend pulsatile perfusion for high-risk renal patients, most evidence is based on intra-aortic balloon pump (IABP) studies, with limited evidence for centrifugal pumps. We aimed to evaluate whether pulsatile CPB using a centrifugal pump reduces postoperative AKI in patients undergoing cardiac surgery.

Methods

This retrospective study analyzed 824 patients who underwent cardiac surgery between December 2008 and December 2023. The patients were divided into pulsatile perfusion (PP) and non-pulsatile perfusion (NP) groups. Propensity score matching was adjusted for the baseline characteristics, resulting in 265 matched pairs. The primary endpoint was postoperative AKI, defined by the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Subgroup analyses were performed based on estimated glomerular filtration rate (eGFR).

Results

In the matched cohort, the PP group had a significantly lower incidence of AKI than the NP group (20.8 vs. 34.3%; odds ratio, 0.5; 95% confidence interval, 0.33–0.75; P < 0.001). A subgroup analysis showed that patients with a preoperative eGFR of 15–60 had a significantly lower incidence of AKI in the PP group (28.3 vs. 47.1%; P = 0.005). No significant differences were observed in secondary outcomes, including hemodialysis, cerebrovascular events, and in-hospital mortality.

Conclusions

Pulsatile CPB using a centrifugal pump significantly reduced the incidence of postoperative AKI in cardiac surgery patients, particularly in those with preoperative renal impairment.