Dextran vs. Crystalloid Priming Solution in Cardiac Surgery: A Randomized Trial on Acute Kidney Injury

Area of Science:

• Cardiology
• Nephrology
• Anesthesiology

Background:

• Acute kidney injury (AKI) is a common complication following cardiac surgery using cardiopulmonary bypass (CPB).
• Crystalloid priming solutions may contribute to AKI through hemolysis and fluid shifts.
• Previous studies suggested potential renal benefits of dextran-based solutions.

Purpose of the Study:

• To test if a dextran-based CPB priming solution reduces postoperative AKI in high-risk cardiac surgery patients.
• To evaluate the impact of dextran priming on perioperative hemolysis, fluid balance, and renal replacement therapy needs.

Main Methods:

• A randomized, controlled, double-blinded, multicenter trial comparing dextran vs. crystalloid CPB priming solutions.
• Inclusion of adult patients with a calculated postoperative AKI risk of ≥50%.
• Primary outcome: AKI incidence within 96 hours postoperatively; secondary outcomes: hemolysis, fluid balance, renal replacement therapy.

Main Results:

• The trial was terminated early due to slow enrollment (92 patients analyzed).
• Postoperative AKI occurred in 81% of the dextran group vs. 53% of the control group (RR 1.53, p=0.004).
• The dextran group showed reduced intraoperative hemolysis and better fluid balance, but no significant difference in renal replacement therapy.

Conclusions:

• In high-risk patients undergoing cardiac surgery with CPB, dextran-based priming solutions were associated with a significantly increased risk of postoperative AKI.
• The findings contradict the initial hypothesis and highlight the need for careful consideration of priming solutions in CPB.
• The study underscores the challenges in conducting CPB trials and the importance of rigorous research despite enrollment difficulties.