Heart surgery patients can considerably reduce their risk of developing post-operative acute renal failure by taking aspirin for five days before undergoing surgery.

The study, conducted by Professor Jianzhong Sun (M.D., Ph.D.), professor and attending anesthesiologist at Jefferson Medical College, Thomas Jefferson University, Philadelphia, US, was presented Sunday June 10th at the European Anesthesiology Congress in Paris.

The researchers enrolled 3,219 patients who were due to undergo coronary artery bypass graft (CABG), valve surgery or both, to participate in the study. Acute kidney failure or injury is a common post-operative complication and has a significant impact on the survival of patients undergoing heart surgery.

2,247 participants were given aspirin for five days before their operation and 972 receive no aspirin. Although the team had no record of the precise dose taken, the normal dose for aspirin that is taken over a period of time is between 80-325mg.

The researchers took into account various factors, such as disease, age, and other medications, and found that acute kidney failure occurred in just 3.8% of patients taking aspirin (86 out of 2,247) versus 6.7% of patients not taking aspirin (65 out of 972). These findings show that aspirin can reduce the risk of acute renal failure by around 50%.

Professor Sun explained:

“Thus, the results of this clinical study showed that pre-operative therapy with aspirin is associated with preventing about an extra three cases of acute renal failure per 100 patients undergoing CABG or/and valve surgery.”

According to Professor Sun, acute renal failure or injury “significantly increases hospital stay, the incidence of other complications and mortality. From previous reports, up to 30% of patients who undergo cardiac surgery develop acute renal failure. In our studies, about 16-40% of cardiac surgery patients developed it in various degrees, depending upon how their kidneys were functioning before the operation. Despite intensive studies we don’t understand yet why kidney failure can develop after cardiac surgery, but possible mechanisms could involve inflammatory and neurohormonal factors, reduced blood supply, reperfusion injury, kidney toxicity and/or their combinations.”

Professor Sun continued:

“For many years, aspirin as an anti-platelet and anti-inflammatory agent has been one of the major medicines in prevention and treatment of cardiovascular disease in non-surgical settings. Now its applications have spread to surgical fields, including cardiac surgery, and further, to non-cardiovascular diseases, such as the prevention of cancer.

Looking back and ahead, I believe we can say that aspirin is really a wonder drug, and its wide applications and multiple benefits are truly beyond what we could expect and certainly worthy of further studies both in bench and bedside research.”

More trials are needed in order to investigate how aspirin helps prevent post-operative kidney failure, says Sun. He believes that the effect might also be seen in individuals undergoing non-cardiac surgeries.

“For instance, the PeriOperative ISchemic Evaluation-2 trial (POISE-2) is ongoing and aims to test whether small doses of aspirin, given individually for a short period before and after major non-cardiac surgeries, could prevent major cardiovascular complications such as heart attacks and death, around the time of surgery.”

The team also found that high blood pressure, diabetes, heart failure, heart disease, and diseases of the vascular system were all separate risk factors for post-operative acute renal failure.

Written By Grace Rattue