Intravenous amino acid therapy for kidney function in critically ill patients: a randomized controlled trial

Area of Science:

• Nephrology
• Critical Care Medicine
• Nutritional Support

Background:

• Acute kidney injury (AKI) is a common complication in critically ill patients, leading to prolonged intensive care unit (ICU) stays and increased mortality.
• Currently, no proven interventions exist to prevent AKI or preserve glomerular filtration rate (GFR) in this population.
• Preclinical and limited clinical data suggest that amino acid supplementation may offer renal protection against ischemic injury.

Purpose of the Study:

• To investigate the efficacy of daily intravenous (IV) amino acid supplementation in preserving kidney function among critically ill patients.
• To determine if amino acid therapy can reduce the duration of renal dysfunction in the ICU setting.

Main Methods:

• A multicenter, phase II, randomized clinical trial was conducted in Australia and New Zealand involving 474 critically ill adult patients.
• Participants were randomly assigned to receive either daily IV amino acid supplementation (up to 100 g) or standard care.
• Key outcomes included the duration of renal dysfunction, estimated GFR (eGFR) using creatinine and cystatin C, urinary output, and renal replacement therapy (RRT) use.

Main Results:

• The primary outcome, duration of renal dysfunction, did not differ significantly between the amino acid therapy group and the standard care group.
• Amino acid therapy led to a significant improvement in eGFR, peaking on study day 4, and a significant increase in daily urine output.
• A trend towards increased RRT use in the amino acid group was observed but was not statistically significant after adjusting for baseline imbalances.

Conclusions:

• Daily IV amino acid supplementation did not alter the duration of renal dysfunction in critically ill patients, failing to meet the primary study objective.
• Despite not impacting the primary outcome, amino acid therapy demonstrated beneficial effects on markers of kidney function, including improved eGFR and increased urine output.
• Further research may be warranted to explore the specific role and optimal timing of amino acid therapy in managing critically ill patients with or at risk for AKI.