Health

‘Bloodless’ surgery

Mark Nichols July 24 2000
Health

‘Bloodless’ surgery

Mark Nichols July 24 2000

‘Bloodless’ surgery

Health

New techniques lessen blood loss and reduce the risk of infection

In 1986, Brian Muirhead, an anesthesiologist at Winnipeg’s Health Sciences Centre, took on the case of a 70-yearold man who urgently needed surgery for a bleeding ulcer. Normally, such a procedure would be routine. But the patient belonged to the Jehovah’s Witnesses, a Christian denomination that rejects blood transfusions on religious grounds. During surgery, anesthesi-

ologists are responsible for keeping patients stable, and two of Muirhead’s colleagues refused to accept the case because of the risks it posed. Muirhead accepted the challenge—and when bleeding occurred during the operation, he resorted to a little-used method of pumping

saline solution into the patient to keep his blood pressure up.

The procedure was a success, and it reinforced Muirhead’s growing belief that “we were giving too many blood transfusions. I thought it was time to look at alternatives.”

Muirhead and like-minded physicians across Canada did just that, developing new techniques that, over the past five

years, have turned so-called bloodless surgery into a major medical trend, spurred both by concerns over the future supply of donated blood—and by many patients’ fears of getting a disease vims from a transfusion.

Because of the fast response that most emergency cases demand, practitioners of the more time-consuming “bloodless” techniques still apply them largely to elective surgery. “There will always be absolute need for donated blood,”

says Dr. Nigel Colterjohn, a Hamilton orthopedic surgeon. Canadian Blood Services, which took over from the Canadian Red Cross in 1998, reports that donations have just begun to recover after the tainted-blood scandal that left thousands of Canadians infected with HIV and the hepatitis C virus in the 1980s. But experts fear that demand from the aging boomer gener-

ation could outstrip supply over the next 20 years. “The majority of surgical blood transfusions are for people over 60,” says Muirhead. “If you want to economize on the use of blood, then the best way is to try to reduce demand.” The battery of techniques to reduce the demand for existing supplies includes surgeons’ growing use of electrocautery instruments that seal blood vessels to prevent bleeding as they slice through tissue, drugs that reduce blood

loss during operations and others, such as erythropoietin, that stimulate blood production in patients’ bone marrow. In the operating room, physicians can use devices that suck up blood lost during surgery, filter it and pump the blood back into patients.

Another blood conservation strategy flows from the realization in recent years that most patients’ hemoglobin (red blood cell) count can fall drastically without endangering life. Now, under a controversial process called hemodilution, some doctors remove quantities of an anesthetized patient’s blood before

surgery and replace it with a saline solution. Then, when bleeding occurs during an operation, less actual blood is lost and the patient’s own blood is pumped back in.

Besides eliminating the need for transfusions in many cases, bloodless surgery reduces the risk—however slight—of infection from tainted blood. “I tell patients that the blood system is safer than it’s ever been,” says Colterjohn, referring to the CBS’s stringent conditions for blood donation. But even transfusions of clean donor blood can pose a risk of infection by temporarily suppressing the immune systems of surgery patients. Notes Colterjohn, who performs hip and knee replacements in older patients: “Infection is something we want to avoid at all costs.”

Although national statistics on the use of “bloodless surgery” are it is becoming common-

place in some areas. Dr. Brian Berry, who runs transfusion services in Victoria and surrounding region, estimates conservation practices reduced the amount of blood used for transfusions by 40 per cent between 1993 and 1998. But for Berry and other experts, educating more physicians is the next step in promoting a vital new trend in medicine’s life-anddeath involvement with human blood.

Mark Nichols