How does intraoperative blood salvage work?
Blood conservation is good medicine, and intraoperative blood salvage is a key surgical conservation strategy. For years the slogan “Donate blood – save a life” has been used to encourage blood donation. Transfusion, however, is not risk free, and modern medical practice has come to understand that avoiding unnecessary blood transfusions also saves lives.
Advancing technology, as well as techniques originally developed to care for Jehovah’s Witnesses, who refuse blood on religious grounds, has led to innovative methods of conserving a patient’s own blood supply, even during major surgery. Once used only on “bloodless medicine” patients, these strategies are now being employed to improve care for all patients.
One example is intraoperative blood salvage (also called auto-transfusion) which recovers a patient's own blood by suctioning it directly from a surgical incision. It is then filtered, washed, and returned to the patient. The technique, developed as a method of avoiding allogeneic (donor) transfusion, is used when significant surgical blood loss is anticipated.
Anticoagulant medication (to prevent clotting) is mixed with the blood at the tip of the suction apparatus. The blood is filtered and collected. From there the blood may be returned directly to the patient, containing all plasma proteins, including clotting factors. Or, as is the practice at Allegheny General Hospital, the blood can be centrifuged (spun) to separate the red blood cells, and washed with saline, which removes anticoagulation, plasma-free hemoglobin, and plasma proteins. The washed red blood cells are then returned to the patient.
The salvaged blood may remain outside the body during much of the surgery and be re-infused toward the end of the procedure. Some patients request that a closed-loop system be used, maintaining a direct connection to the patient at all times. Hospitals with formal bloodless medicine programs, like the one here at Allegheny General Hospital, have considerable experience with these techniques.
Patients who wish to avoid allogeneic (pronounced al-oh-juh-nee-ik) blood transfusions during surgery should talk with their physicians about their options as soon as surgery is discussed. Advance planning, specially trained staff, and specific equipment in the operating suite may be required.