"Looking at the impact of nonfatal myocardial infarction (MI), refractory ischemia, and major or minor bleeding on the crude odds ratios of mortality risk at 180 days, he found that the risk of dying was increased by 410% in patients who had experienced major bleeding. Only nonfatal MI had a greater impact (560%). Even minor bleeding more than doubled the mortality risk."
New Research Emerges on Dangers of Blood Loss
Walter Alexander, MS
At a recent multidisciplinary investigator’s forum on blood management, called "Inflammation, Hemostasis and Blood Conservation Strategies," Bruce Spiess,MD, director of Virginia Commonwealth University’s Reanimation Engineering Shock Center in Richmond (VCURES), made what might, at first blush, appear to be an audacious request: "We need somewhere between 50 to 100 large-scale clinical trials." He was requesting new research to help define at what point transfusion should take place for patients undergoing cardiac and other surgical procedures.
The event, held at Emory University School of Medicine in Atlanta from September 30 to October 1, was sponsored by Bayer Pharmaceuticals. Bayer makes aprotinin (Trasylol®), a protease inhibitor that helps to maintain hemostasis by shutting down inflammation associated with transfusion. Aprotinin is often used in cardiac surgery and, increasingly, in orthopedic surgery to reduce blood loss. In clinical trials, aprotinin has reduced the need for transfusion by 35% to 48%, and the reduction in blood loss, Dr.Spiess said, has been as high as 80%. The largest meta-analysis, by Sedrakyan et al., indicated an overall reduction of 39%.1
Why the urgency? After all, according to one forum attendee, Steven Steinhubl, MD, Associate Professor of Medicine at the University of Kentucky College of Medicine, the adage for interventional cardiologists putting stents into coronary arteries, has been this: It’s easier to replace blood than to replace myocardium.
Until recently, it has been common practice to combine femoral artery access for balloon catheters and stents with drugs that are designed to calm inflamed acute coronary syndrome (ACS) blood components, often leading to the loss of a few liters of blood into the draping or, worse yet, into the leg. This bleeding has been considered a relative non-issue; the stock solution has been to infuse just a few units.
Newer compelling data, however, are turning blood loss into a frontline concern. At the European Society of Cardiology, 2005 Congress, held in Stockholm, Sweden (September 3–7), professor Salim Yusuf, MD, from McMaster University in Hamilton, Ontario, Canada, presented data on the OASIS 5 study in a Hot Line session. OASIS 5, the largest ACS trial on record with more than 20,000 patients, compared an older and a newer low-molecular-weight heparin, fondaparinux (Arixtra ®, GlaxoSmithKline) and enoxaparin (Lovenox®, Sanofi-Aventis). Major bleeding was a primary endpoint...(Click here for complete article)