Nutritional support in acute kidney injury requiring continuous renal replacement therapy: from metabolic alterations to clinical recommendations.

This narrative review examines the metabolic and nutritional challenges faced by critically ill patients with acute kidney injury (AKI) undergoing continuous renal replacement therapy (CRRT). Recent evidence and international guidelines were reviewed to synthesize the current understanding of nutrient losses, metabolic alterations, and clinical implications. CRRT induces additional depletion of amino acids, proteins, water-soluble vitamins, and trace elements, aggravating the catabolic stress inherent to critical illness. It also modifies carbohydrate, lipid, and micronutrient metabolism, while also providing or removing non-nutritional calories through dialysate and anticoagulation solutions. These complex interactions demand a tailored nutritional strategy that compensates for therapy-related losses and metabolic disturbances. A coordinated, multidisciplinary approach integrating nutritional assessment, close monitoring, and timely adjustment of therapy may optimize metabolic recovery, reduce complications, and improve clinical outcomes in this high-risk population.