Restrictive blood transfusion approach safe for heart surgery patients


LONDON, ON – New research has validated the use of a new, more restrictive method of using blood transfusions during heart surgery. The restrictive approach led to the use of fewer transfusions, with no increase risk to kidney health.

Dr. Amit Garg, Scientist at Lawson Health Research Institute (Lawson) and Nephrologist at London Health Sciences Centre (LHSC), and his colleagues, conducted a clinical trial with high risk patients who were undergoing cardiopulmonary bypass surgery. The trial examined 4,531 participants across 73 centres in 19 countries. Participants were randomized into two groups, one receiving the restrictive approach (transfuse only if hemoglobin is below 7.5 g/dL), and the other receiving a more liberal approach (transfuse if hemoglobin is less than 9.5 g/dL), regularly used in cardiac surgery today.

On average, participants in the restrictive transfusion group received 38% fewer transfusions than those in the liberal group. Both approaches were found to be equally safe, as the restrictive group did not have a higher rate of acute kidney injury. Risks were similar between participants with and without chronic kidney disease before surgery.

Reducing the number of transfusions could prevent adverse events related to transfusions, conserve blood supply, and reduce health care costs.

“Over 20 million cardiac surgeries are performed worldwide each year. With this being one of the more common reasons for using blood in the hospital, and an average of about 3 units of red blood cells used per patient, this suggests that approximately 20 million units of blood could be saved each year without influencing the chance that a patient will develop post-operative kidney injury,” says Dr. Garg.

The study, titled “Safety of a Restrictive versus Liberal Approach to Red Blood Cell Transfusion on the Outcome of AKI in Patients Undergoing Cardiac Surgery: A Randomized Clinical Trial,” is published in the Journal of the American Society of Nephrology.

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