Big blood transfusions questioned

Study finds trauma patients no more likely to die if given saline injections

A new Canadian study is challenging the widespread practice of transfusing blood early and aggressively into bleeding trauma patients.

The older approach was to give car crash and other trauma patients saline — water plus salt — intravenously and blood only if tests showed they were anemic from blood loss, or the blood wasn’t clotting properly.

Many patients died of uncontrolled bleeding.

Then in 2007, American military doctors working in Iraq and Afghanistan reported that bleeding soldiers were more likely to survive if doctors began transfusing vast amounts of blood immediately without waiting for blood results.

Now, a new study comparing blood-based resuscitation versus conventional resuscitation found more blood wastage and complications in patients automatically transfused with blood, but with no difference in death rates.

The study is the latest to question the safety and benefits of blood transfusions, now one of the most overused procedures in medicine.

Hemorrhage is the leading cause of preventable, in-hospital deaths among trauma patients, Dr. Sandro Rizoli, director of the trauma program at Toronto’s St. Michael’s Hospital, and co-author of the study in the Canadian Medical Association Journal.

Earlier studies have shown that, minutes after a major trauma — such as a car crash, falling from a height, gunshot or stab wounds — one in four patients can’t clot properly. Their bodies release massive amounts of natural substances that prevent clots from forming, increasing their risk of bleeding to death.

“If you are bleeding from a hole in your liver, and on top of that your body cannot form good clots, it’s a bad combination,” Rizoli said.

Until 2007, “a patient would come in bleeding, you would try to stop the bleeding and at the same time start intravenous saline — nothing more than water and salt,” he said.

“If the blood work showed your patient needs blood, you would give blood.”

The U.S. military study quickly changed the way trauma centres worldwide resuscitate patients. “The standard became to treat patients with a big bleed by assuming they’re not clotting and immediately transfusing with blood,” Rizoli said.

The transfusion scheme uses a combination of equal parts red blood cells, plasma — the liquid portion of blood that contains clotting factors — and platelets, which make blood sticky and more likely to form clots.

Rizoli’s team conducted the first randomized trial of the formula — know as 1:1:1 — in 78 trauma patients treated at Sunnybrook Health Sciences Centre in Toronto.

The study showed more wastage of blood in the 1:1:1 patients and more respiratory complications that required patients to be connected to mechanical ventilators, without a meaningful difference in death rates.

Rizoli said bigger and better studies are needed to evaluate the safety of “one-to-one.”