Efficacy of perioperative recombinant human brain natriuretic peptide for preventing acute kidney injury after cardiac surgery: Rationale, design, and study protocol for a multicenter, double-blind, randomized controlled trial (PROTECT-CS).

Summary

PROTECT-CS is an investigator-initiated, multicenter, double-blind, placebo-controlled randomized trial designed to test whether perioperative recombinant human brain natriuretic peptide prevents acute kidney injury after high-risk on-pump cardiac surgery. The planned sample is 694 patients, with Kidney Disease: Improving Global Outcomes-defined acute kidney injury within 7 days as the primary endpoint and clinically meaningful renal and mortality outcomes as secondary endpoints.

Key Findings

• The trial plans to randomize 694 high-risk patients undergoing elective on-pump cardiac surgery.
• Patients receive rhBNP at 0.01 µg/kg/min or matched saline from anesthesia induction through 48 ± 2 postoperative hours.
• The primary endpoint is acute kidney injury within 7 postoperative days using Kidney Disease: Improving Global Outcomes criteria, with renal replacement therapy, MAKE-30, MAKE-90, mortality, and length of stay as secondary outcomes.

Clinical Implications

The trial will determine whether rhBNP should be incorporated into perioperative management for patients at high risk of cardiac-surgery acute kidney injury. Until results are available, routine prophylactic use should not be assumed.

Limitations

• This publication reports the study protocol and provides no efficacy or safety results.
• The findings may be most applicable to selected high-risk patients undergoing elective on-pump cardiac surgery and may not generalize to emergency surgery or other cardiac procedures.

Future Directions

Completion of PROTECT-CS should establish whether rhBNP reduces acute kidney injury and major adverse kidney events, while prespecified subgroup analyses should assess effects according to baseline renal function, surgical risk, and cardiopulmonary bypass characteristics.