The drug Trasylol by Bayer Pharmaceutical, a heart surgery drug has been studies at 69 of the world's leading cardiac centres. This study was published containing advisories on the side effects of the drug on heart surgery patients. The study was conducted by New England Journal of Medicine (NEJM) by Mangano et al in January of 2006.

Every year, there are more or less a million people who undergo surgery following a heart attack. There is a big chance of extreme bleeding during the surgery and this happens to the majority of the patients. Options of the antifibrinolytic drugs that can be taken by the patients include Trasylol (Aprotinin) from Bayer, Amicar (aminocaproic acid), or Cyklokapron (tranexamic acid) to limit the excessive loss of blood. The function of antifibrinolytic is to stop plasmin; an enzyme. This enzyme is prevented from breaking down blood clots which lessens the bleeding.

Significant concerns about the safety of Trasylol had been raised by studies conducted and published by the NEJM. The study showed alarming concerns like Trasylol doubles the risk of kidney failure together with serious side effects like stoke and heart attack. This drug has been available in the market since 1993 and is approved to be used on cardiac surgeries. 10,000 patients are estimated to be on kidney dialysis due to intake of Trasylol. Trasylol, a Bayer drug compared to generic drugs which are lest costly like aminoaproic acid and tranexamic acid were also studied but were not linked to kidney failure.

After these studies, the FDA has approved the revision of label for Trasylol and continued studies to verify the information regarding its safety. September 21, 2006, a public meeting of the Cardiovascular and Renal Drugs Advisory Committee initiated by the FDA was conducted to discuss the safety of Trasylol. In this meeting, the public advisory committee gave recommendations on the changes of the label of Bayer on Trasylol. This includes a warning saying Trasylol increases risk on damage of the kidney. Take note of the significant cost of the dialysis treatmetnt. Annually, a patient suffering from kidney failure from Trasylol would have to pay more than $66,000

Those who experience kidney dysfunction have to go through dialysis; this is a renal replacement therapy acting as an artificial kidney. Dialysis cleans the blood of a patient from impurities and toxins that the kidney could no longer eliminate in the body. A large number of patients undergo this treatment; the blood is circulated outside through a machine known as hemodialyzer, cleaned and then returned to the patient's body. Two types of dialysis treatment are the hemodialysis and peritoneal dialysis. Typically, hemodialysis is performed three times a week in which a session would last for 3 up to 5 hours. Both treatments hemodialysis and peritoneal dialysis are very costly.

September 29, 2006, through the information from Bayer, the FDA announced more findings regarding Trasylol. It said that in addition to serious problems in the kidney, the drug is also linked to increase in the risk of death, strokes and congenital heart failure. The study also concluded that the use of aminocaproid acid, a generic drug as replacement for Trasylol could help prevent more kidney failure and linked dialysis treatment of 11,050 patients a year would save $1 billion yearly. Tranexamic acid, a generic drug to replace Trasylol is estimated to prevent 9790 renal complications that would require a yearly dialysis treatment with the same annual cutback on medical costs.