Convalescent Plasma

Overview

Convalescent plasma therapy involves transfusing the plasma (the liquid part of the blood) from someone who has recovered from an infectious disease to help you fight the same illness. This plasma contains antibodies that were produced by the donor’s body during their battle with the disease. By receiving this plasma, your immune system gains the ability to recognize and attack the infection using these transferred antibodies.

Reasons for undergoing the procedure

Healthcare providers often use convalescent plasma to treat new viral infections that can cause severe illness, especially when other treatments or vaccines are not yet available. This therapy can help prevent life-threatening conditions. It has been used to treat COVID-19, viral hemorrhagic fevers like Ebola, SARS (severe acute respiratory syndrome), bird flu (avian influenza), and H1N1 (swine flu).

Risks

Blood and plasma transfusions are generally safe due to thorough testing and screening of donors and their blood. Although complications are uncommon, convalescent plasma therapy does carry some risks, including:

  • Fever
  • Allergic reactions
  • Infections at the IV site
  • Chronic infections such as HIV, hepatitis B, and hepatitis C (these are extremely rare)

Before the procedure

Before donating, a convalescent plasma donor undergoes a thorough screening process to ensure eligibility. This includes general screening for all plasma donations and specific tests tailored to convalescent plasma.

The specific screening requirements for convalescent plasma depend on the virus or pathogen it targets. Typically, donors must be fully recovered from the illness and have a high antibody level in their plasma to qualify for donation.

Generally, the following factors will disqualify you from donating blood plasma:

  • Illness: If you have a fever, feel unwell, or are currently taking antibiotics for an infection, you are ineligible to donate plasma.
  • Certain medical conditions: The American Red Cross screens for 23 medical conditions when evaluating blood and plasma donors. Some conditions, like hepatitis and HIV, automatically disqualify you, while others may require special circumstances for eligibility.
  • Certain medications and medical procedures: Certain treatments, such as blood transfusions or surgeries, may disqualify you from donating plasma.
  • Travel to certain regions: Recent travel to specific areas of the world, where the risk of contracting certain illnesses like Ebola is higher, can disqualify you from donating.
  • Recent tattoo or piercing: Receiving a body piercing or tattoo within the past 12 months typically disqualifies you from donating plasma.

Before you receive convalescent plasma, your doctor will review your medical history, blood type, and overall health to ensure you are eligible for the treatment.

During the procedure

Convalescent plasma therapy comprises two distinct procedures, each involving different individuals: the plasma donor and the plasma recipient.

Donor
If you meet the eligibility criteria for convalescent plasma donation, you will likely undergo the process at a blood donation center. The steps involved in donating convalescent plasma are as follows:

  • You will recline comfortably in a chair.
  • A phlebotomist, will sanitize and disinfect the area of your arm where the needle will be inserted.
  • Following the cleaning process, the phlebotomist will insert a needle into one of your veins.
  • A specialized device called a plasmapheresis machine will extract blood from your vein and separate the plasma from the rest of your blood.
  • The plasmapheresis machine will then return your red blood cells and platelets, along with some saline solution, to your body through the same needle.
  • Upon completion of the procedure, the phlebotomist will carefully remove the needle and instruct you to apply pressure to the site with gauze until bleeding stops. Subsequently, they will cover the site with a bandage.
  • You will likely rest for at least 10 minutes, during which time a doctor will monitor your well-being.
  • Once you are deemed fit, you will be offered food and beverages before being discharged to return home.

The procedure takes one to two hours on average.

Recipient
Convalescent plasma is administered using the same protocol as ordinary plasma transfusions, which entails the following steps:

  • You will likely recline on a comfortable bed or chair.
  • A phlebotomist will sanitize and disinfect the area of your arm where the needle will be inserted.
  • Following the cleaning process, the phlebotomist will insert a needle into a vein in your arm and establish an IV (intravenous) line.
  • The convalescent plasma will then flow slowly from its container, through a rubber tube, and into the vein in your arm.
  • Upon completion of the procedure, the phlebotomist will carefully remove the needle and instruct you to apply pressure to the site with gauze until bleeding stops. Subsequently, they will cover the site with a bandage.
  • Following the transfusion, your doctor will monitor your vital signs to ensure there are no adverse reactions.

The duration of a plasma transfusion might range from one to four hours.

Outcome

Receiving convalescent plasma may not yield immediate improvement in your condition, and distinguishing its specific impact among other treatments can be challenging. Occasionally, convalescent plasma may not produce any discernible effect. After donating convalescent plasma, it’s essential to prioritize hydration by drinking ample water for the following day or so. Additionally, it’s advisable to avoid strenuous activities during this time.