October 26, 2009: Cardiac surgery is advised for a number of disorders of the heart and acute kidney injury is one of the common complications of cardiac surgery. Studies have noted that about 30% of the individuals undergoing cardiac surgeries develop kidney injuries wherein about 1% of these individuals require dialysis.

Several factors have been identified as risk factors that increase the incidence of kidney injury in individuals undergoing cardiac surgeries. Women are more commonly noted to develop kidney injuries, while individuals with conditions such as chronic obstructive pulmonary disease, diabetes, peripheral vascular disease, renal insufficiency, pre-existing kidney diseases and congestive heart failure are also at a higher risk. In some cases the kidney injury may be directly or indirectly related to the cardiac surgery procedures itself.

Several preoperative, intraoperative and postoperative factors have been identified that causes injury to the kidney. The common point noted among all these factors was that, any factor that affected the blood circulation to the kidneys caused kidney injury. The administration of medications such as diuretics, nonsteroidal anti-inflammatory drugs (NSAID), angiotensin-converting enzyme inhibitors (ACEI), or angiotensin receptor blockers (ARB) further increased the risk, especially in those with pre-existing kidney disorders. These medications had toxic effects on the blood supply to the kidneys.

Although several other medications have been tried to treat individuals with kidney failure during cardiac surgery, their efficacy has not been proven. The number of deaths associated with kidney failures during cardiac procedures still remains unchanged.