Apheresis is the procedure used to collect stem cells from your blood. The collection of stem cells on average takes 1 to 2 days with approximately 5 hours per collection. The collection is performed in the Infusion Center at P/SL Medical Center. You will see a Transplant physician or a Mid-level Practitioner daily prior to collection.
The apheresis machine withdraws blood from your central line (CVC) and circulates it through a centrifuge, which separates out your stem cells and returns the remaining blood back to you. There is only a small amount of your blood (a little over one cup) in the separator machine at any given time. The procedure is the same for allogeneic donors, but peripheral IV catheters are placed instead of a central line. During the procedure you may relax in your chair while watching television, movies, or reading.
There are very few side effects associated with the apheresis procedure. The main side effects are:
- Numbness/tingling of fingers or toes
- Numbness/tingling of skin, especially lips
- Cold Intolerance
- Muscle cramps
All of these symptoms can be signs of low calcium in your blood. Citrate, a calcium-binding substance used during the collection of your stem cells, prevents blood from clotting while it is circulating through the machine. Eating a breakfast that includes calcium-rich foods (for example milk, yogurt or cheese), may reduce or eliminate symptoms caused by the low calcium. Alert an apheresis staff member if you experience any these symptoms or have any other concerns.
During the time you are undergoing apheresis, daily lab tests are done to count the number of stem cells collected. Each patient has a target goal of stem cells to collect for transplant. It may take a number of days to attain this goal. The apheresis staff will notify you when your target goal has been met. The minimum number of stem cells required for transplant is 2,000,000 per kilogram of your body weight.
For autologous patients, your cells are frozen (cryopreserved) and stored under special conditions until they are needed for transplant. Cryopreserved cells can be stored indefinitely.
For allogeneic patients, stems cells from related donors are most often infused into the patient on the same day they are collected from the donor, eliminating the need for cryopreservation. Fresh stem cells are viable for 48 hours. In the event that all of the stem cells are not needed, the excess cells will be cryopreserved for possible future use.
Bone Marrow Harvest
In some situations, a bone marrow harvest may be recommended for the collection of stem cells instead of apheresis. If you will require a bone marrow harvest, your physician will discuss the procedure with you in detail.