Defining Acute Kidney Injury
Epidemiology and Outcomes of AKI
Intrinsic Renal Failure
Prevention of AKI
Treatment of AKI
Postrenal Renal Failure
Be able to define acute renal injury.
Understand the epidemiology of renal injury in the ICU.
Recognize the increase in mortality associated with acute renal injury.
Identify the pathophysiology of acute kidney injury.
Evaluate and treat a patient with acute kidney injury.
Acute kidney injury in the ICU increases morbidity and mortality. There are now accepted criteria that define the level of injury based on either an increase in creatinine or a decrease in urine volume. The higher the stage of renal injury, the worse the outcome will be. More sensitive biomarkers are presently under investigation that will enable a diagnosis of acute kidney injury even before the creatinine begins to rise. When approaching a patient with an elevated creatinine, the clinician needs to determine whether the cause is the result of a reversible decrease in renal perfusion, injury to the kidney itself, or obstruction to urine flow. Prerenal and postrenal etiologies should be identified and promptly treated. The most common cause of kidney injury in critically ill patients is sepsis. It is now known that sepsis, by activating numerous inflammatory cytokines, causes blood flow obstruction at the microvascular level and tubular apoptosis. The treatment of patients with kidney injury is aimed at preventing complications. Renal replacement therapy should be considered early, especially in patients with oliguria. Many of the patients who suffer acute kidney injury never completely regain renal function. Because of the increased mortality associated with kidney injury, every effort should be made to identify patients at high risk and avoid insults to the kidney.