Bone Marrow Transplant |
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Autologous Transplant Guide: Blood Counts and Transfusions
Waiting for Engraftment
High doses of chemotherapy or radiation cause the bone marrow to stop producing new blood cells. The new bone marrow does not recover immediately after it has been transplanted. The cells of the transplanted marrow will travel to the bones, reseed the marrow space and go through a growth process before the mature cells are released from the bone marrow into the blood stream. It will take at least eight to 14 days from the day of transplantation before your blood counts start to recover.
The term "blood counts" refers to the number of blood cells circulating in the blood stream. There are three main types of blood cells: red blood cells, white blood cells and platelets. While the bone marrow is still growing, these cells will need to be replaced through transfusions.
Engraftment is the term used to describe when your new marrow begins to function and produce cells. While awaiting engraftment, no mature cells leave the marrow and enter the blood stream. Your blood counts will show very low values and you will require careful monitoring by the health care team. The goal is to support you with red blood cell and platelet transfusion until you are producing cells again. After transplantation, you will receive a bone marrow growth factor, called G-CSF, which will help the cells of the bone marrow grow and mature. The growth factor is given as an injection under the skin daily.
The Various Blood Cells
White blood cells (WBCs) fight infection. These include neutrophils and lymphocytes, amongst others. Neutrophils, also known as polys or granulocytes, account for the majority of circulating WBCs. They are responsible for fighting primarily bacterial and fungal infections. Bone marrow growth factors like neupogen or G-CSF make neutrophil counts rise. The neutrophil count should be at least 500 (usually reported on the lab test results as 0.5) by 30 days after transplantation.
Bone marrow growth factors like G-CSF (also called neupogen) make neutrophil counts rise. Neutrophils are not usually transfused except in special circumstances. The use of antibiotics to fight infection and growth factors to help the bone marrow grow are usually adequate until the neutrophil count is up.
Lymphocytes are the backbone of the immune system. These cells are responsible for fighting viruses and for forming antibodies that will attack infectious organisms. Lymphocyte function is generally abnormal for as long as three months after transplantation. This means you may develop severe infections even when the white blood cell count is normal.
Red blood cells (RBCs) carry oxygen throughout the body. The hematocrit means the percentage of blood that contains red cells. The hemoglobin is the part of the red blood cell that carries oxygen. The hemoglobin is proportional to the hematocrit. Anemia occurs when there are not enough red blood cells in the body. Symptoms include shortness of breath, weakness, fatigue, dizziness, headache, and irritability. A red cell transfusion is given through your catheter over an average of two to three hours. Additional transfusions may be needed as an outpatient, or you may be given erythropoietin (Epo), a red blood cell growth factor.
Platelets help control bleeding. When you cut yourself, the platelets form a clot or plug to stop the bleeding. Some symptoms of a low platelet count include petechiae (small red dots on the skin), easy bruising and bleeding from the gums or nose.
A platelet transfusion is given routinely when the platelet count falls too low to prevent serious bleeding into the tissues. You will begin to need platelet transfusions about one week after the start of chemotherapy. The number of transfusions needed per week varies from patient to patient and ranges from one to seven transfusions per week. The need for platelet transfusions will continue for three to six weeks, sometimes longer depending on how your bone marrow is recovering or what medications you are receiving.
There are two types of platelet transfusions:
Single donor platelet transfusions use platelets that are collected from one person in a procedure called apheresis, which takes about two to two and a half hours. In this procedure, blood is taken from the donor and circulated through a machine called a blood cell separator. This machine separates the platelets into a collection bag and returns the remaining blood constituents to the donor. Most single donor platelets are from the family and friends of the patient. Your platelet donors do not need to have your blood type. You will not receive platelets from your designated donor if a more compatible single donor unit is available. Random donor platelet transfusions use platelets that are pooled from several units of whole blood donated by several different random blood donors. These are the most common type of platelets to be transfused.
Potential platelet donors must pass preliminary testing before donating, which involves a written history form, checking vital signs and taking a small blood sample. All persons donating blood are carefully screened for infectious diseases to make sure their blood is safe.
You may sometimes experience some uncomfortable reaction to your blood product transfusions. Some of these reactions may include fever, chills, shaking, itching and skin rashes. Infrequent side effects are back pain and shortness of breath. . If you have side effects, medications are available to limit the reactions. The red blood cells and platelets are irradiated and filtered, and frequently medications may be used before the transfusion to minimize any side effects. Your nurse will watch carefully for any of these reactions, and you also need to report any symptoms to your nurse.
Donating Blood Products
It is helpful if you arrange to have family
members donate blood products for you to use during your
hospitalization. Anyone can be a blood donor as long as
they complete the blood bank screening procedures and pass
all the tests. Donations can be given at any donor center;
however only the ones given at UCSF Medical Center or Blood
Banks of the Pacific in San Francisco will be available
for you during your hospitalization. The Blood Donor Center
at UCSF can help organize blood donation for family and
friends. For more information, please call (415) 476-1000
and ask for the Blood Donor Center.
More Information:
Reviewed by health care specialists at UCSF Medical Center.
Last updated May 8, 2007
This information is for educational purposes only and is not intended to replace the advice of your doctor or health care provider. We encourage you to discuss with your doctor any questions or concerns you may have.
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