Acute kidney injury in
critically ill patients is often a complication of an underlying condition such as organ failure,
sepsis, or
drug therapy. In these patients, stress-induced hypercatabolism results in loss of body cell mass. Unless nutrition support is provided,
malnutrition and negative
nitrogen balance may ensue. Because of metabolic, fluid, and
electrolyte abnormalities, optimization of nutrition to patients with
acute kidney injury presents a challenge to the clinician. In patients treated with conventional intermittent
hemodialysis, achieving adequate
amino acid intake can be limited by
azotemia and fluid restriction. With the use of
continuous renal replacement therapy (CRRT), however, better control of
azotemia and liberalization of fluid intake allow
amino acid intake to be maximized to support the patient's metabolic needs. High
amino acid doses up to 2.5 g/kg/day in patients treated with CRRT improved
nitrogen balance. However, to our knowledge, no studies have correlated increased
amino acid intake with improved outcomes in
critically ill patients with
acute kidney injury. Data from large, prospective, randomized, controlled trials are needed to optimize the dosing of
amino acids in
critically ill patients with
acute kidney injury who are treated with CRRT and to study the safety of high doses and their effects on patient morbidity and survival.