PROTECTION

Population:

Adult patients (n=3511) undergoing cardiac surgery with cardiopulmonary bypass at 22 centers across three countries.

Intervention:

Intravenous infusion of a balanced mixture of amino acids at a dose of 2 g per kilogram of ideal body weight per day, administered for up to 3 days.

Comparison:

Placebo group receiving Ringer’s solution.

Outcome:

The primary outcome was the occurrence of acute kidney injury (AKI) as defined by the Kidney Disease: Improving Global Outcomes (KDIGO) creatinine criteria. The study found that AKI occurred in 26.9% of the amino acid group versus 31.7% of the placebo group (Relative Risk [RR], 0.85; 95% Confidence Interval [CI], 0.77 to 0.94; P=0.002). Stage 3 AKI was also reduced in the amino acid group (1.6% vs. 3.0%; RR, 0.56; 95% CI, 0.35 to 0.87). The use of kidney-replacement therapy was slightly lower in the amino acid group (1.4% vs. 1.9%). There were no substantial differences in other secondary outcomes or adverse events between the groups.

Clinical Insights:

This study suggests that the use of intravenous amino acids may be beneficial in reducing the occurrence and severity of AKI in patients undergoing cardiac surgery with cardiopulmonary bypass. The reduction in Stage 3 AKI and the use of kidney-replacement therapy, although modest, supports the potential protective effect of amino acids on renal function in this high-risk population. However, the lack of significant differences in other secondary outcomes and adverse events indicates that while the intervention is beneficial, it may not drastically change overall clinical outcomes beyond AKI prevention. This could be considered in the perioperative management of patients at risk for AKI following cardiac surgery.