Bone marrow harvesting is a procedure in which healthy marrow-containing stem cells are collected from a healthy donor. Stem cells are collected in two ways. One method is peripheral collection and another method is aspirated from the bone with the help of a largely bored needle. Most of the sites used to collect marrow are hip bone, sometimes it is collected from sternum bone as well. The procedure is carried out in Operation Theater, where general anesthesia is given to the donor So, that the donor will not feel the pain of the needle. peripheral stem cells are collected by inserting a central line in the chest of the patient or Donor depending upon the type of transplant.
How much will it take to Collect Bone Marrow?
The time of bone marrow harvesting from bone depends upon the amount of bone marrow required for the recipient (the patient). Normally, it takes around 45 to one hour once started. On the other hand peripheral stem cell collection takes around 3-4 hours. Peripheral Harvesting is used in autologous as well as in allogenic transplants. Bone marrow harvesting is mostly done in allogenic transplants.
Selection of donor for bone marrow transplant:
A healthy donor is selected by a test called HLA typing. The donor may be from siblings or he or she may be unrelated.
Preparing a patient for peripheral stem cell collection in autologous transplant:
As in autologous transplant stem cells are collected from the patient and reinfused to the same patient.
Growth factors Administration:
Before stem cell collection patient is given some injections called growth factors to boost up the marrow. Moreover, this is done to collect the maximum amount of stem cells.
Central line insertion:
A large bore central line is placed in the chest or neck of the patient. The central line contained two lumens. One lumen is used to draw blood into the pheresis machine. While another lumen is used to return the blood to the body.
Preservation of stem cells in Autologous Transplant:
The collected stem cells are saved in the laboratory after adding preservatives. And are frozen at -80 degrees centigrade or 2 – 8 degrees centigrade depending upon the time to reinfuse. If the cells have to re-infuse after 72 hours then they are frozen. If have to infuse within 72 hours the cells are kept at 2 to 8 degrees centigrade. where in an allogenic transplant cells are infused into the patient on the same day of collection.
Bone Marrow Harvesting In the Operation Theater
Donors are not to eat anything from midnight. A blood sample is done in the morning at least 2 -3 hours before the procedure and a cannula for medications and fluids is in Operation Theater, After shifting to Operation Theater, general anesthesia is given. The donor is placed in a particular position called the prone position.
During the Procedure of Bone Marrow collection
After giving anesthesia, the bone marrow harvesting team including bone marrow harvesting consultants, operation room technicians, and BMT nurses will start the procedure of collecting marrow by inserting a special needle called a spinal needle or bone marrow needle. The amount of bone marrow amount depends upon the patient’s (Recipient) weight as well as the donor’s weight.
After Bone Marrow collection/Harvesting
After the procedure, shift the donor to the post-operative area for monitoring for at least 30 minutes to one hour un till the donor is conscious. Then transfer to the normal floor with special instructions like food restriction again for at least 3-4 hours after the procedure to avoid any anesthesia complications like vomiting. Assess bleeding from the puncture site. A complete blood count test is carried out to check hemoglobin levels, if there is a drop in HEMOGLOBIN levels, a packed RBC could be transfused before discharge. Your diet starts with clear liquid like green tea or juice, Once you tolerate an oral diet your consultant will discharge you home with some iron supplements and some painkillers.
Seek medical attention
In case of the following consult your physician:
- Fever 101F.
- Severe pain regardless of painkillers.
- Uncontrolled bleeding from the bone marrow aspiration site
- If have hematoma swelling at the line site in peripheral stem cell collection.
Usually, there is no harm to the donor. The donor can resume his/her daily routine activities just the same day of the transplant.