Acute kidney injury (AKI) is one of the most common organ dysfunctions impacting ICU (intensive care unit) patients. Early diagnosis using the various classification systems and interventions that can be aided by use of biomarkers are key in improving outcomes. Once the patient meets criteria of AKI, many patient specific factors determine the optimal timing for and mode of renal replacement therapy. There are several special considerations in surgical ICU patients with AKI including management of intracranial hypertension in those with cerebral edema, anticoagulation in high-risk bleeding patients, and use of contrast imaging. This article provides a focused review of the essential aspects of diagnosis and management of AKI in the critically ill or injured surgical patient.