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Jehovah's Witnesses, whose religious beliefs don't allow for blood transfusions, seem to do as well or better than other patients after heart surgery, new research suggests.

Doctors sometimes give heart patients a transfusion of red blood cells if tests show they have low levels of hemoglobin or hematocrit after the procedure to prevent severe anemia, despite some transfusion-related risks. Because Jehovah's Witnesses don't have that option, surgeons typically take extra pre-procedure precautions - such as giving patients B vitamins and iron - to ensure their red blood cell counts don't get too low during surgery. And those precautions seem to be working, according to the new study.

"The current management strategy... does not appear to place patients at increased risk, and actually some of the complications are fewer," said Dr. Colleen Koch, who worked on the study at the Cleveland Clinic. That could have implications for managing people who are okay with getting blood transfusions - but might be better off if they could avoid one, Koch said.

She and her colleagues compared 322 Jehovah's Witnesses who had heart surgery at their center between 1983 and 2011 without a blood transfusion to an equal number of patients who were similar in most ways, but who did get transfusions. Most of them were in for bypass surgeries. A similar number of patients - 10 Jehovah's Witnesses and 14 in the comparison group - died in the hospital. One Witness had a heart attack during a procedure, compared to nine people who had blood transfusions.

Jehovah's Witnesses also spent less time in the hospital and the intensive care unit, on average, and were less likely to need an extra operation because of bleeding problems. Members of the religion believe passages in the Bible prohibit them from accepting blood transfusions, which means doctors have had to get creative about how to prep them for major operations.

"We pull out all stops to minimize the blood loss, to conserve what they've got, to take care of them pre-operatively so they don't come in anemic," Koch said of treating Jehovah's Witnesses. Now, she told Reuters Health, "We've demonstrated the current practice of how we care for them is safe."

Koch said there's no reason why the same approach of making sure a patient is at low risk of anemia and prepping them with extra supplements can't be applied to non-Witnesses. Anemia, along with excessive bleeding, is the main reason some patients end up needing a transfusion, she said.

Getting a transfusion is tied to a higher risk of complications, Koch's team has shown.

And there's "enormous variation" when it comes to which patients get a transfusion - between zero and 88 percent of bypass patients, depending on where their procedures are done, according to Dr. Victor Ferraris, a surgeon from the University of Kentucky Chandler Medical Center in Lexington.

Patients going in for heart surgery, Koch said, should ask their surgeon about their risk of needing a transfusion, and about how to lower it. Some of those strategies may line up with tools that have been developed for Jehovah's Witnesses.

"We need to examine some of these practices more closely and see if they can't be more broadly applicable," Koch said.

"That's the fundamental question," said Ferraris, who wrote a commentary published alongside the study in the Archives of Internal Medicine. "If you can operate on all these Jehovah's Witnesses and do it safely and have comparable outcomes without transfusing, then why not do it in everybody?"

He said one limitation of the new study is Jehovah's Witnesses getting heart surgery may be healthier than other patients: they don't smoke, drink alcohol or do intravenous drugs, and doctors probably avoid doing heart surgery if they're so sick they'll likely need a transfusion. That could help account for their lower risk of complications.

Still, Ferraris said more patients would benefit - and fewer would need a blood transfusion - if everyone went through a pre-operation workup similar to precautions taken with Jehovah's Witnesses.