Transfusiones de sangre no necesitadas en cirugías

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In Pittsburgh and across the nation, surgeons are doing as many operations as possible without using a drop of donated blood.

The approach, sometimes known as bloodless surgery, emphasizes techniques that boost red blood cell counts before and after an operation, and cut blood loss while it is going on.

According to doctors at Allegheny General Hospital’s Center for Bloodless Medicine and Surgery, the techniques free up blood for use in true emergencies, such as major car accidents, at a time when it remains difficult to get people to donate blood. About 8 million Americans donate blood each year — 5 percent of those eligible.

It also saves money.

Dr. Jan Seski, a cancer surgeon who has pioneered bloodless surgery methods in Pittsburgh, said there was no doubt how important blood transfusions can be in some cases.

“Blood products are as safe as they’ve ever been,” he said, “and we use them when we need to. Let’s not minimize the necessity of blood in certain circumstances.”

In many operations, however, there are ways to avoid transfusions, and doing so can not only make doctors better surgeons, but it also can cut infections, complications and healing time.

“Not all surgeons can do this because not all surgeons can do surgery without losing an excessive amount of blood,” said Dr. Seski, chief of gynecologic oncology at Allegheny General. “It’s just like anything else in life. There are certain degrees of expertise.”

Studies have shown that patients who get transfusions have more infections and complications after surgery, Dr. Seski said. Those who undergo cancer surgery have more recurrences if they get transfusions, he added.

Even when it is matched properly by blood type, donated blood “just overwhelms the immune system and plugs it up for a while, so the body has trouble recognizing foreign invaders,” Dr. Seski said.

“If we could do surgery without using blood,” Allegheny General heart surgeon George Magovern Jr. said, “that would probably be best.”

The savings accompanying bloodless surgery are not just in buying less blood.

“The savings to hospitals that have employed a comprehensive program of reducing blood transfusions is, like, $3 million to $4 million a year,” Dr. Seski said. “It’s saving on the cost of nursing time, the cost of blood, the reduction in infections, side effects and complications.”

Dr. Seth Perelman, associate chief of anesthesiology at the nation’s leading bloodless surgery center, Englewood, N.J., Hospital Medical Center, said many hospitals use blood transfusions in up to half their surgeries.

In his hospital, it’s down to 15 percent.

Dr. Jonathan Waters, chief of anesthesiology at Magee-Womens Hospital and head of UPMC’s surgical blood management program, said it was difficult to know how much the growing number of blood-saving programs is reducing demand for transfusions around the country.

It is harder to cut down on blood use in a large multihospital health system such as UPMC’s than at community hospitals such as Englewood, he said.

Nevertheless, Dr. Waters said, blood conservation programs can have a big impact. When he helped found the Cleveland Clinic’s blood management program nine years ago, it saved the hospital 10,000 units of blood in its first year.

Right now, he said, UPMC is working to eliminate the practice of having patients donate their own blood ahead of time for use during surgery, and instead use machines to salvage their blood during the operations. It also is trying to get its major hospitals accredited in blood management by the American Association of Blood Banks.

Many of today’s bloodless surgery techniques were developed because of the strong beliefs of a religious sect that has its roots in Pittsburgh.

The Jehovah’s Witnesses, founded in Pittsburgh in 1872 by Charles Taze Russell, rely on verses from Leviticus, Deuteronomy and Acts as the basis for their refusal to accept blood transfusions.

They interpret the Bible to mean that they can’t donate their own blood ahead of time because it would be completely separated from their bodies.

Like many other surgeons involved in bloodless medicine, Dr. Seski got his start treating Jehovah’s Witnesses.

After years of experience with them, he feels their refusal to accept transfusions should be viewed as any other medical complication.

“If a patient comes into my office and she weighs 400 pounds and I have to do an operation on her,” he said, “I don’t say go and lose the weight before I take your cancer out. I have to operate on this person, despite her complications.

“The same thing is true of diabetes, hypertension, severe heart disease. … All of these things complicate a surgical procedure. If the patient comes in and says I don’t want blood, that’s just another hurdle we have to get over to cure this patient of cancer.”

Allegheny General, UPMC and other sites use five primary methods to avoid or limit blood transfusions:

Hormones. Doctors use synthetic versions of the hormone erythropoietin, which manufactures oxygen-carrying red blood cells in the bone marrow, to build up patients’ hemoglobin counts before and after surgery.

The hormones ensure patients won’t be anemic going into surgery, and help rebuild their red blood cell counts afterward in four to six weeks, instead of the three to four months it used to take, Dr. Seski said.

Hemodilution. In many surgeries, doctors will remove one to two pints of blood from a patient before surgery begins and route it through a machine that separates it into red blood cells and clear plasma.

They put the plasma and clear saline solution back into the patient so that his blood volume remains the same. Because red blood cells have been removed, however, any blood lost during surgery will have far less hemoglobin in it than normal.

They also can suction some of that blood and put it through the same filtering machine, and then, when the surgery is done, they can put the red blood cells back into the patient.

Cautery. Surgeons use electric and argon laser beam scalpels to seal off blood vessels as they operate, slowing blood loss. Surgical clamps which can cut off the blood supply to operative areas are also important.

Microsampling. Instead of drawing vials of blood during surgery and sending them to a lab, surgeons can now use machines that analyze a single drop of blood inside the operating room to check on its clotting and oxygen-carrying ability.

That not only saves time, but also lets doctors know more precisely whether the patient needs plasma for clotting or red blood cells.

Pediatric blood tubes. One of the stealthiest ways patients lose blood in the hospital is when their blood is drawn for testing after surgery.

If a patient goes into the intensive care unit, Dr. Seski said, standard blood testing could cost a pint of blood every week. By using diminutive pediatric blood tubes, though, hospitals still can do their tests and reduce much of that blood loss, he said.

There is no better proof of the value of these techniques than Wade Moss, of Murrysville.

Mr. Moss, 46, a former custodian in the Gateway School District, had major colorectal surgery in early 2002, had a hip replacement later that year and had his other hip replaced in 2004, all without receiving transfusions.

Mr. Moss, now on disability, is actively involved in Jehovah’s Witnesses ministry and never had the slightest doubt about refusing transfusions.

“People think blood is a lifesaving fluid that’s going to make you feel better,” Mr. Moss said. “But in reality, it’s the [blood] volume you’re losing that hurts you more than anything.

“Not taking blood, from a lot of doctors’ perspective, is actually safer and it helps the doctor become a better surgeon. If a doctor needs a lot of pints of blood, it could mean he’s being sloppy. And we, as Jehovah’s Witnesses, have raised that awareness.”

Many of the hospitals that pioneered bloodless surgery techniques were smaller centers that wanted to attract Jehovah’s Witnesses, UPMC’s Dr. Waters said.

But now, major institutions such as the Cleveland Clinic, the Mayo Clinic, Johns Hopkins and UPMC are jumping on the bandwagon, he said.

One example of the growing interest in the discipline, he said, is that the Web site for the Society for the Advancement of Blood Management has grown from 4,000 to 13,000 unique visitors in recent months,

Bloodless surgery also fits well with other medical trends, Dr. Seski said.

More and more doctors are doing minimally invasive surgery which uses small incisions and tubes and scopes to perform operations, he said, and research is moving forward on artificial hemoglobin products that might reduce the need for blood donations even further.

These advances will become all the more important when baby boomers hit retirement and sharply increase the expected number of surgeries and cancer treatments.

But for any given surgery, transfusions are likely to decrease in the future, Dr. Seski said.

“I think we’re going to be using less blood 10 years from now than we’re even using now,” he said.

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