Skip to Main Content

Welcome to

Together is a new resource for anyone affected by pediatric cancer - patients and their parents, family members, and friends.

Learn More
Blog Community

Apheresis for Stem Cell Collection

What is apheresis?

Apheresis is a procedure to remove a part of the blood. This procedure may be done to collect cells such as blood-forming (hematopoietic) stem cells.

The collection of stem cells from blood in the veins is also called blood stem cell harvest or peripheral blood stem cell donation.

An apheresis machine takes blood from a vein and separates the blood into parts (plasma, platelets, white blood cells, and red blood cells). The stem cells are removed from the blood. The rest of the blood is returned to the body through a vein. Only a small amount of blood is out of the body at any time. The parts of the blood that are removed are stored for later use.

Female teen undergoing apheresis procedure for stem cell collection

Apheresis is a procedure to remove a part of the blood. This procedure may be done to collect cells such as blood-forming (hematopoietic) stem cells.

Stem cells for transplant can come from a donor or the patient.

  • An allogeneic transplant uses healthy stem cells from another person (donor) to replace a patient’s damaged or destroyed stem cells. 
  • An autologous transplant uses a patient’s own stem cells to replace cells that have been damaged or destroyed by high doses of chemotherapy or radiation. 

Before apheresis, a medicine called granulocyte-colony stimulating factor (G-CSF) will be given. G-CSF is a blood growth factor that increases the number of stem cells that circulate in the blood. G-CSF is given as an injection (shot) once a day. The care team will let you know how many shots are needed before apheresis.

What to expect during apheresis

Apheresis takes 3 to 8 hours per day. Several sessions may be needed to collect enough of the cells. If more than 1 session is needed, apheresis is usually done once a day. Staff will explain what to expect and answer any questions.

You will be in bed during the apheresis procedure. Wear comfortable, loose-fitting clothing. During the procedure, you can rest, watch a movie, read, or do other quiet activities in bed.

The procedure is usually done with 2 lines (double needle procedure). The medical team will decide the best way to place the lines based on vein size and the number of treatments needed. Types of access include:

The medical team will take steps to reduce the risk of infection. All tubes that touch the blood are sterile (free from germs) and are only used once.

An apheresis nurse will stay at the bedside to monitor for any reactions or problems.

Because you will have tubes attached to the apheresis machine, you will not be able to leave the room once the procedure has started. Portable toilet equipment will be provided if needed.

In addition to the apheresis procedure, other tests or procedures may be needed. These include:

  • Lab tests: Blood tests may be performed to measure different parts of the blood and check blood cell counts. If blood counts are low, a blood transfusion might be needed before apheresis begins.
  • Tests for infectious disease: Lab tests will also look for certain infectious diseases such as hepatitis B and C virus, human T cell lymphotropic virus (HTLV-I/II), syphilis, West Nile Virus, and human immuno-deficiency virus (HIV). You will be notified if test results indicate an infectious disease.
  • Blood prime: If red blood cell counts are low or the patient or donor is smaller in size, staff might need to add donated blood to the apheresis machine’s tubing before starting the procedure. This helps make sure that the red blood cell count does not become too low.

Possible side effects of apheresis

The side effects of apheresis are like those that can happen when people donate whole blood. Any side effects are usually mild and temporary. There is always the risk of rare or unknown side effects.

Side effects of apheresis may include:

  • Nausea
  • Dizziness
  • Fainting
  • Pain or bruising at the site where the needle is placed
  • Blood loss
  • Infection
  • A reaction to any blood products received during apheresis
  • If apheresis is stopped before it is complete, a small amount of the blood may not be returned to the body.

Apheresis may cause a lower platelet count or white blood cell count. This decrease is usually small. However, medicines such as NSAIDs or aspirin can increase the risk of bleeding. Do not take these medicines while getting G-CSF or for 2 weeks after stem cell collection unless instructed by your health care provider.

Side effects caused by blood-thinning medicine

During apheresis, your provider may give a medicine called citrate. This is a blood-thinning medicine. It keeps the blood from clotting in the apheresis machine.

Citrate may cause side effects that include:

  • Muscle cramping
  • Numbness
  • Chills
  • Tingling sensations
  • Strange or metallic taste in the mouth
  • Feeling anxious
  • Seizures (in rare cases)

The care team may give calcium, either by mouth or by vein, to prevent or treat these reactions.

When to contact a health care provider

There is always the risk of very rare or unknown side effects. If you notice any side effects, unusual feelings, or discomfort during apheresis, tell a nurse or a doctor right away.

Please talk to your health care provider or blood donor center staff if you have questions about apheresis.

Key points about apheresis for stem cell collection

  • Apheresis is a procedure to remove a part of the blood. This procedure may be done to collect hematopoietic (blood-forming) stem cells for transplant.
  • Collecting stem cells from blood in the veins is also called peripheral blood stem cell donation.
  • Most side effects of apheresis are mild and are like what you might have from giving blood.
  • During apheresis, a nurse will watch for any side effects of the procedure or medicines given during the procedure.
  • Talk to your health care provider about care instructions for before and after the procedure.


Reviewed: December 2023