Therapeutic Apheresis: What to Expect

Apheresis (pronounced ah-fair-EE-sis) is a procedure in which blood is withdrawn from your body, one or more components are separated and removed or modified, and the remaining blood is returned to you. When done for medical treatment rather than donation, it is called therapeutic apheresis.

This guide explains the different types of therapeutic apheresis, why they are used, what vascular access is required, and what to expect during and after the procedure.

What Is Therapeutic Apheresis?

In therapeutic apheresis, your blood is processed outside your body by a machine (the apheresis machine) that separates blood components by density using centrifugation or filtration. The machine continuously withdraws blood, separates it, removes the targeted component, and returns the rest.

Depending on what is being removed or modified, the procedure may take 2–5 hours per session. Most patients require a series of sessions — from a few to many, depending on the condition being treated.

Types of Therapeutic Apheresis

Therapeutic Plasma Exchange (TPE) — also called Plasmapheresis

What is removed: Plasma — the liquid portion of blood. Plasma contains antibodies, immune complexes, proteins, and other molecules.

Why it is done: To remove harmful substances circulating in the plasma. This includes:

Autoantibodies causing conditions such as myasthenia gravis, Guillain-Barré syndrome, neuromyelitis optica, anti-NMDA receptor encephalitis
Immune complexes in thrombotic thrombocytopenic purpura (TTP) — TPE is lifesaving in TTP
Abnormal proteins in certain neurological conditions
Toxins or drug overdoses in specific cases

What replaces it: Because plasma contains proteins essential for clotting and other functions, removed plasma is replaced with a substitute — typically albumin (a blood protein), fresh frozen plasma (FFP), or a combination of the two. The choice of replacement fluid is made by your physician based on your condition.

What to expect: A single session typically takes 2–4 hours. Patients often receive multiple sessions over several days for acute conditions (e.g., daily for 5–7 days for TTP or Guillain-Barré), or ongoing maintenance sessions for chronic conditions.

Low-Density Lipoprotein (LDL) Apheresis

What is removed: LDL cholesterol (the “bad” cholesterol) from the blood.

Why it is done: For patients with familial hypercholesterolemia — an inherited condition causing extremely high LDL levels that cannot be adequately controlled with medications. Extremely high LDL causes premature and severe cardiovascular disease. LDL apheresis can reduce LDL by 50–75% per session.

Frequency: Typically every 2 weeks, on an ongoing basis.

What to expect: Sessions last 2–3 hours. Cholesterol levels return to pre-treatment levels between sessions, so regular treatment is essential. This is typically a long-term, ongoing therapy.

Red Cell Exchange (RCE) — also called Erythrocytapheresis

What is removed: Your red blood cells (erythrocytes), which are replaced with donated red blood cells.

Why it is done:

Sickle cell disease — the most common indication. Red cell exchange replaces sickle-shaped red cells with normal donor cells, reducing complications including stroke, acute chest syndrome, and pain crises.
Severe malaria
Severe polycythemia (too many red blood cells) in some cases

What to expect: Sessions take 2–3 hours. Sickle cell patients often receive red cell exchange on a regular schedule (typically monthly or every 4–8 weeks) to prevent complications.

Extracorporeal Photopheresis (ECP)

What is removed: White blood cells (lymphocytes) are collected, treated with a light-sensitizing agent (8-methoxypsoralen) outside the body, exposed to ultraviolet-A light (which kills the cells or alters their function), and then returned to the body.

Why it is done:

Cutaneous T-cell lymphoma (CTCL / mycosis fungoides / Sézary syndrome)
Graft-versus-host disease (GVHD) after stem cell or bone marrow transplantation
Some cases of organ transplant rejection

What to expect: Sessions take 3–5 hours. Treatment is typically given on two consecutive days every 2–4 weeks, often for months to years.

Leukocytapheresis

What is removed: White blood cells (leukocytes).

Why it is done: For conditions with extremely high white cell counts (leukocytosis) that cause symptoms — such as acute leukemia with very high blast counts, where the excess cells can impair circulation. This is often an emergency or urgent procedure.

Vascular Access for Apheresis

Apheresis requires high-flow vascular access — the machine needs to withdraw and return blood rapidly (at rates of 50–150 mL/minute). This is much faster than standard IV infusion. The access requirements differ by procedure type and patient.

Peripheral access (antecubital veins)

If your antecubital veins (the large veins at the inside of the elbow) are large enough and accessible, peripheral access may be sufficient for some apheresis procedures. Two sites are used — one for withdrawal, one for return — or a single large-bore needle with a special technique.

Advantages: No catheter placement procedure; access via standard needle sticks. Disadvantages: Not suitable for all patients; can be difficult in patients with small or fragile veins; uncomfortable for repeated procedures.

Temporary apheresis catheter

For patients whose peripheral veins are inadequate or who are starting urgent treatment, a temporary large-bore central catheter (apheresis catheter or dialysis-type catheter) is placed in a large neck or femoral vein. These catheters are specifically designed for high-flow procedures.

Where placed: Internal jugular vein (neck), subclavian vein (chest), or femoral vein (groin) — depending on clinical factors and urgency. How placed: By an interventional radiologist or intensivist under ultrasound guidance, typically at the bedside or in a procedural suite. Local anesthesia is used. Duration: Days to weeks. Not intended for long-term use.

Tunneled apheresis catheter

For patients requiring ongoing, long-term apheresis therapy (such as LDL apheresis patients or chronic ECP patients), a tunneled catheter designed for high-flow apheresis access may be placed as a permanent or semi-permanent solution. This is the same type of tunneled catheter used for long-term chemotherapy or dialysis, but selected for its high-flow capacity.

See: Going Home with a Tunneled Catheter for detailed care guidance.

Arteriovenous fistula or graft (for long-term LDL apheresis)

Some long-term LDL apheresis patients have an arteriovenous fistula created — the same surgical connection used for hemodialysis access. This provides reliable, high-flow access for repeated procedures without the infection risk of a central catheter.

What to Expect During the Procedure

Before you arrive

Eat and drink normally before your session unless specifically instructed otherwise. Being well-hydrated helps blood flow and reduces side effects.
Avoid fasting — low blood sugar during a long procedure is uncomfortable and avoidable.
Wear loose, comfortable clothing. If peripheral access will be used, short sleeves or sleeves that roll up easily are helpful.
Bring something to do — a book, tablet, headphones, or other entertainment for a 2–5 hour procedure.

During the procedure

You are seated in a reclining chair or hospital bed.
The access needles or catheter connections are established.
The apheresis machine is set up and primed.
Blood flow begins — you will feel the machine withdrawing blood.
The machine continuously processes your blood, removing the targeted component and returning the rest.
A nurse or apheresis technician monitors you throughout the entire procedure.
You may eat, drink, read, or watch something during the session. You cannot leave your chair while connected to the machine, but most positions (reclined, sitting up) are comfortable.

Common sensations during apheresis

Tingling or numbness around the lips, fingertips, and feet: This is caused by a temporary drop in ionized calcium due to the citrate anticoagulant used to keep blood flowing in the machine. It is extremely common, not dangerous, and resolves quickly. You may be given calcium supplements (by IV or by mouth) during the procedure to prevent or treat this. Tell your nurse as soon as you notice tingling — it is easily managed.

Feeling cold: Processed blood returning to the body can feel colder than body temperature. Blankets are available; ask.

Mild lightheadedness: Can occur, particularly if fluid shifts are significant. Tell your nurse.

Fatigue: Common during and after longer sessions. Plan to rest afterward.

After the Procedure

Immediately after

Pressure is applied to the access site(s) after needle removal until bleeding stops.
You are monitored briefly before leaving.
Mild fatigue is normal; severe weakness or lightheadedness should be reported.

Later that day and the following day

Fatigue is common after apheresis and may last 24 hours.
Drink fluids to restore volume and help your body equilibrate.
Avoid strenuous physical activity on the day of treatment.
If you received plasma replacement (in TPE), be aware that some people feel mildly off for a day as the body adjusts.

Monitoring and follow-up

Blood tests are typically done regularly throughout your apheresis treatment course to monitor the effect of treatment and watch for complications.
Your physician will review results and adjust the treatment plan accordingly.

Side Effects and Complications

Most apheresis sessions are tolerated well. Known risks include:

Side effect	How common	What to do
Citrate reaction (tingling, numbness)	Very common	Tell your nurse; calcium is given
Fatigue after the session	Common	Rest; resolves within 24 hours
Feeling cold during procedure	Common	Blankets
Mild hypotension (low blood pressure)	Occasional	Nurse monitors; fluid adjustment
Allergic reaction to replacement fluid (albumin or FFP)	Uncommon	Nurse monitors; treated immediately
Access site bruising or bleeding	Occasional	Pressure; report if significant
Infection at catheter site (for catheter access)	Uncommon	Preventable with proper care
Air embolism	Rare	Machine safety systems prevent this

Call your care team if, after leaving the session, you experience: fever, significant bleeding from the access site, severe shortness of breath, chest pain, or unusual swelling.

Questions to Ask Your Apheresis Team

What type of apheresis am I having, and what specifically is being removed?
How many sessions will I need, and over what time period?
What kind of vascular access will I need? Will I need a catheter placed?
How will I know if the treatment is working?
What restrictions, if any, apply on the days of my treatment?
Are there any medications I should stop before sessions?
What are the realistic goals for this treatment — cure, long-term management, bridge to another therapy?

This guide is for educational purposes. Apheresis protocols, access requirements, and replacement fluid choices vary by institution, procedure type, and individual patient factors. Your apheresis team and prescribing physician are your primary sources of guidance for your specific treatment.