Autologous Transplant — Collecting the Cells
The first step in a transplant is to collect the bone marrow cells. The bone marrow is the place where the cells in the blood (red cells, white cells and platelets) are made. When you are a child all the bones in the body contain active bone marrow. As you get older the active marrow is confined to the central bones in the body, the spine, pelvis, ribs, skull, thigh bone (femur) and upper arm (humerus). Of all these places, the easiest to collect marrow from is the posterior pelvis.
Removal of bone marrow — or a harvest — is done in the operating room. Patients — who in autologous transplants are their own donors — are given a general anesthetic, and about 2 pints (1 liter) of bone marrow are removed. Because bone marrow has a lot of blood flowing through it, blood is also removed at the same time as the marrow. Some people become anemic (because they lose hemoglobin when they lose blood) after a bone marrow harvest, so a blood transfusion may need to be given.
An alternative to a bone marrow harvest is called a "peripheral blood stem cell collection." Other names include stem cell collection, blood cell collection, blood stem cell collection and peripheral blood progenitor cell collection. The main advantage of this approach is that the cells grow back faster after the transplant. Another advantage is that it avoids the need for a general anesthetic and a bone marrow harvest.
In this procedure, the patient (i.e., the donor) is given special drugs (examples of drugs used include the growth factor G-CSF, which is also known as Neupogen, or GM-CSF which is also know as Leukine) to push the stem cells out of the bone marrow and into the bloodstream, making collection easier on the patient. Chemotherapy with the drugs Cytoxan, Etoposide or Taxol can also increase the number of stem cells circulating in the blood. When a combination of growth factor drugs and chemotherapy is used, the chances of getting a high number of stem cells are increased.
A central venous catheter is placed in the patient. Apheresis is performed on a healthy volunteer donor (usually a sibling) through two IV's, one in each arm. Blood is withdrawn via the catheter and sent to a machine that separates the stem cells from the plasma and blood. The stem cells are then gathered for transplantation while the plasma and blood return to the patient by way of a catheter in the other arm. This process – the collection of stem cells from the blood – is called apheresis.
The collection is performed over three to four hours. During this time most patients relax in a recliner chair and listen to music or watch a video. There are few side effects that people experience when the stem cells are being collected. Some people get tingling in their fingers from the anticoagulant used (which prevents blood clotting) but this is corrected by giving patients some calcium. Some people say they feel tired the next day.
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