The bone marrow—the sponge-like tissue found in the center of certain bones—contains stem cells that are the precursors of white blood cells, red blood cells, and platelets. These blood cells are vital for normal body functions, such as oxygen transport, defense against infection and disease, and clotting. Blood cells have a limited life span and are constantly being replaced; therefore, the production of healthy stem cells is vital.
In association with certain diseases, stem cells may produce too many, too few, or abnormal blood cells. Also, medical treatments may destroy stem cells or alter blood cell production. Blood cell abnormalities can be life threatening.
Bone marrow transplantation involves extracting bone marrow containing normal stem cells or peripheral stem cells from a healthy donor, and transferring it to a recipient whose body cannot manufacture proper quantities of normal blood cells. The goal of the transplant is to rebuild the recipient’s blood cells and immune system and hopefully cure the underlying disease.
Simply what is bone marrow transplant?
Healthy marrow is infused into people who have had high-dose chemotherapy for one of the many forms of leukemias, immunodeficiencies, lymphomas, anemias, metabolic disorders, and sometimes solid tumors.
Several tests are performed before the bone marrow transplant to identify any potential problems ahead of time. Tests include:
- tissue typing and a variety of blood tests
- chest x ray
- pulmonary function tests
- computed tomography scan (CT or CAT)
- heart function tests, including an electrocardiogram
- and echocardiogram
- bone marrow biopsy
- skeletal survey
In addition, a complete dental exam is needed before the bone marrow transplant to reduce the risk of infection. Other precautions will be taken before the transplant to reduce the patient’s risk of infection.
A triple lumen, central venous catheter (a slender, hollow flexible tube) is surgically inserted into a large vein in the chest during a simple outpatient procedure. The catheter is used to draw blood and infuse chemotherapy and other medications, as well as donor cells, blood product, fluids, and sometimes nutritional solutions. The central venous catheter usually stays in place for about six months after the bone marrow transplant.
Hormone-likemedications called colony-stimulating factors may be given before the transplant to stimulate the patient’s white blood cells. These medications stimulate the white blood cells to multiply, mature, and function. These medications also help the patient’s white blood cells recover from chemotherapy and reduce the risk of infection.
A bone marrow transplant recipient can expect to spend three to four weeks in the hospital, depending on the rate of recovery. In preparation for receiving the transplant, the recipient undergoes ‘‘conditioning,” a preparative regimen (also called marrow ablation) in which the bone marrow and abnormal cells are destroyed. Conditioning rids the body of diseased cells and makes room for the marrow or peripheral stem cells to be transplanted. It typically involves chemotherapy and/or radiation treatment, depending on the disease being treated. Unfortunately, this treatment also destroys healthy cells and has many side effects such as extreme weakness, nausea, vomiting, and diarrhea. These side effects may continue for several weeks.