Process of Bone Marrow Transplantation
These are four stages involved in BMT.
Stage 1: Evaluate the patients for BMT (WORK-UP) usually 14-30 days before
One will undergo complete medical check-up to evaluate one’s suitability to go through the BMT procedure. This involves the following:
- Blood Tests
- Chest X- ray and CT Scans
- Tests to assess the condition of heart and lungs
- Bone Marrow Tests
Patients will be counselled in detail about the procedure, the complications, the chances of success, the cost and the possible length of stay in the hospital. Patient will be encouraged to go through the educational material/booklet and discuss any queries or doubts that he / She might have.
Stage2: Prepare the patient for BMT (CONDITIONING) usually 2-10 days
High dose of chemotherapy or radiotherapy is given to destroy the diseased marrow or destroy the cancer elsewhere and the bone marrow gets damaged as a result. This is needed to create space for new blood stem cell and also to suppress the patient’s own immune system (in case of allogeneic transplant), so that the blood stem cells are not rejected.
The actual process of transplantation
The transplant procedure is actually fairly simple, the stem cells or bone marrow cells to be transplanted are given through the Central Venous line (CVL). The procedure is just like getting a blood transfusion, except the following precautions which has to be taken care of :
- Just before the infusion of the new bone marrow, the patient may be given medication to help avoid any allergic reactions.
- A monitor is used to check breathing, heart rate and blood pressure during the procedure. The nurse monitors closely throughout the infusion of stem cells or bone marrow.
- A doctor is available in the unit and will check the patient periodically. Medications may be given to deal with problems that may arise, such as high blood pressure or a fast heart rate.
Stage 3: Pre-engraftment (before the transplanted blood stem cells start working): (Usually 2-3 weeks)
After high dose chemo-radiotherapy the blood stem cells are destroyed and normal blood cells are not produced. The patients need to be kept in a clean room within the BMT unit in strict isolation during this time. They also need a lot of blood and platelet transfusion. Most patients get serious infections during this period and need treatment with antibiotics.
Stage 4: Post-engraftment (after the transplanted blood stem cells start working)
Early phase (first 3 months)
There are two types of white blood cells: neutrophils and lymphocytes. Neutrophils save us from acute infections and lymphocytes prevent repeated or chronic infections. Once the neutrophil count is above the critical value of 500 cells per microlitre, the patient can come out of critical isolation. This is called engraftment or the first sign that the transplanted blood stem cells are functioning. Soon after the neutrophil increase to normal or near-normal levels and if there is no other complication, the patient can be discharged home. However, regular check-up and blood tests (2-3 times a week) are required. There is also a risk of graft-versus-host disease (GVHD) at this stage.
Late Phase (3 months-12 months)
The immunity against viruses takes a very long time to recover. Even though some of the immunity is restored, the patient is still at risk of infections with viruses and fungus. This is more so if they are being treated for GVHD, which can become chronic and lingering. If the patient is well, the frequency of check-ups and blood tests reduce over several months.