Nonselective Extracorporeal Blood Purification Reduces AKI in High-Risk Cardiac Surgery Patients: SIRAKI02 trial

Cardiac surgery-associated acute kidney injury (CSA-AKI) continues to be a major concern after cardiopulmonary bypass (CPB). While several strategies have been suggested to mitigate CSA-AKI, such as extracorporeal blood purification, there is limited understanding of the impact of EBP using an acrylonitrile-sodium methallylsulfonate/polyethyleneimine membrane during CPB. To fill this knowledge gap, Xosé Pérez-Fernández, Institut de Investigació Biomédica de Bellvitge L’Hospitalet de Llobregat, Barcelona, Spain, and colleagues aimed to assess whether the application of an EBP device in a non-emergency cardiac surgery population leads to a reduction in CSA-AKI following cardiopulmonary bypass (CPB).

For this purpose, the researchers conducted a double-blind, randomized clinical trial in two tertiary hospitals in Spain. They enrolled patients aged 18 and older, at high risk for CSA-AKI, undergoing non-emergent cardiac surgery from June 15, 2016, to November 5, 2021, with follow-up until February 5, 2022. Of the 1,156 patients assessed, 343 were randomized (1:1) to receive either the nonselective EBP device connected to the CPB circuit or standard care. The primary outcome measured was the rate of CSA-AKI within seven days post-randomization.

The study led to the following findings:

• Among the 343 randomized patients (169 receiving EBP and 174 receiving standard care), the average age was 69, with 119 females.
• The rate of CSA-AKI was 28.4% in the EBP group compared to 39.7% in the standard care group, showing an adjusted difference of 10.4%.
• Most predefined clinical secondary and post hoc exploratory endpoints showed no significant differences.
• A sensitivity analysis indicated that EBP was particularly effective in reducing CSA-AKI among patients with chronic kidney disease, diabetes, hypertension, low left ventricular ejection fraction (<40%), and lower body mass index (<30).
• There were no differences in adverse events between the groups.

"The findings indicated that employing a nonselective EBP device connected to the CPB circuit in a non-emergency cardiac surgery population significantly reduced CSA-AKI incidence within the first seven days post-surgery," the researchers concluded.

However, the researchers noted several limitations: inaccurate urine output collection may obscure true CSA-AKI rates post-ICU, serum creatinine changes could be affected by volume status, and findings may not apply to patients with late AKI. Additionally, blinding wasn't possible, some data were missing, and results may not generalize beyond two centers.

Reference:

Pérez-Fernández X, Ulsamer A, Cámara-Rosell M, et al. Extracorporeal Blood Purification and Acute Kidney Injury in Cardiac Surgery: The SIRAKI02 Randomized Clinical Trial. JAMA. Published online October 09, 2024. doi:10.1001/jama.2024.20630