The goal of this study is to see if an infusion of amino acids given to adult male and female patients during cardiac surgery can help prevent acute kidney injury that commonly occurs when patients undergo cardiac surgery needing cardiopulmonary bypass. The main question the study aims to answer is if a short infusion of amino acids given to study participants during their scheduled heart surgery can decrease rates of acute kidney injury - which will be measured by biological markers of kidney injury in the urine.

The study will be conducted in 2 phases. Participants in the first phase will receive the current standard of anesthetic care for patients having heart surgery and markers of acute kidney injury will be measured before and after their surgery. Participants in the second group will receive the anesthetic standard of care plus a short infusion of amino acids during their surgery. They will also have markers of kidney injury measured before and after their surgery. This study is based on prior studies that showed amino acid infusions are protective against kidney injury; however, these past studies did not look at markers of kidney injury in the urine.

Inclusion Criteria:

• Male and female patients 18 years of age or older undergoing elective cardiac surgery requiring cardiopulmonary bypass.
• Anticipated stay of at least one night in the ICU following cardiac surgery.
• Eligible patients must have a baseline serum creatinine measurement obtained during the current hospitalization, or within 365 days of the current hospitalization.
• Patients agree to participation and completed informed consent process.

Exclusion Criteria:

• Preoperative or planned post-operative need for renal replacement therapy.
• Stage IV or greater chronic kidney disease, defined as estimated glomular filtration rate of less than 30 mL/minute per 1.73 M^2 of body surface area as calculated by the Cockcroft-Gault equation.
• Emergent cardiac surgical patients and patients undergoing orthotopic heart transplant.
• Any patient who has a history of renal transplant.
• Patients who have a documented allergy or hypersensitivity to one or more of the amino acids.
• Patients with cognitive impairment who cannot provide consent.
• Patients with congenital alteration of amino acid metabolism.
• Any patient who declines to participate in the study.