Epidemiology and pathophysiology of cardiac surgery-associated acute kidney injury

Acute kidney injury (AKI) remains a serious complication of cardiac surgery. An understanding of the epidemiology and pathophysiology of AKI in cardiac surgery patients is crucial to early recognition and proper management.

The article will review the current criteria used for defining AKI and the most recently published incidence rates of AKI in the cardiac surgery population. Variables associated with AKI will be reviewed. The cause of cardiac surgery-associated AKI is multifactorial involving genetic factors as well as insults because of nephrotoxins, ischemia and reperfusion, cardiac dysfunction, venous congestion, inflammation, and oxidative stress.

Investigators should aim to use consistent criteria for defining AKI in future studies. Efforts should be taken to use actual measurements rather than estimated values of baseline serum creatinine whenever possible. Further study of the more recently proposed pathophysiologic factors contributing to cardiac surgery-associated AKI, such as circulating damage-associated molecular patterns, venous congestion, and genetic predisposition, are warranted.