Heart surgeons who performed aortic valve replacement operations for over 750 patients have found from analyzing data on complications that strategies to reduce the need for donor blood stocks are safe and improve outcomes.
The study's authors - from the New York University Langone Medical Center - reviewed heart surgeries carried out at the center for 778 patients needing a replacement aortic valve and have published their findings in the journal of the Society of Thoracic Surgeons.
Led by Drs. David Yaffee and Eugene Grossi, the team concludes that implementing ways to reduce the need for blood during and after surgery did successfully reduce red blood cell transfusion without increasing the risk of death or illness.
The authors reviewed the clinical and transfusion records of 391 patients undergoing the operation before the implementation of a "blood conservation strategy," comparing these with data from 387 patients having the surgery once the new policy was in place.
They analyzed patient morbidity, mortality and blood product utilization, and found positive results.
Dr. Yaffee concludes:
"Implementation of blood conservation strategies can be safely completed for aortic valve replacement patients while helping to limit unnecessary transfusion, avoiding transfusion-associated complications and decreasing costs."
The new research adds to other findings, published in The Lancet in May 2013, that blood transfusions were being overused during common heart surgery.
Transfusions can be limited 'without causing patient harm'
The current authors comment that guidelines in force from the Society of Thoracic Surgeons (STS) and the Society of Cardiovascular Anesthesiologists (SCA) - recommending that surgical teams conserve blood stocks - are not widely followed, with red blood cell (RBC) transfusion rates varying greatly for cardiac operations, "between 10% and 95%."
The paper adds that this may be because the blood conservation techniques are sophisticated, requiring before surgery:
- Pharmaceutical boosts to RBC volume
- Blood drawn from the patients themselves.
Such protocols also need the leadership of cardiothoracic surgeons, which is "frequently absent."
"Our results suggest that the blood conservation clinical practice guidelines already developed by STS and SCA for coronary artery bypass patients can be safely extended to patients undergoing aortic valve surgery," Dr. Grossi says. He adds:
"While some patients do require transfusion for a safe operation, this study shows that we can limit transfusions without causing harm to the patient."
The heart surgeons found no difference in death rates or major complications between the two groups that could be attributed to the policy being in force.
For patients who received two or more units of red blood cells, however, there was a higher rate of major complications:
- Renal failure
- Respiratory failure, or
Less major complications were also more frequent for the heart surgery patients given at least two units of transfusion:
- Gastrointestinal complications
- Renal failure needing dialysis, and
- Respiratory failure.
US blood transfusion services
America's Blood Centers and the American Red Cross both collect blood donations from around the US - the former supplying half the country's needs through a network of over 600 non-profit community centers, and the latter supplying about 40% of blood demand via mostly mobile collection.
In June 2013, the American Medical Association (AMA) called for a change in policy, recommending that gay men should donate blood. The AMA wants the FDA to overturn its current policy that bars donations from men who have sex with other men.
In October, meanwhile, researchers from the Cleveland Clinic in Ohio said that adopting modern inventory management strategies for blood collection could greatly reduce blood storage time and that fresh blood "may be better for patients."