A plasma transfusion is the introduction of donor plasma, one of the key components of blood, to a patient's circulatory system. Blood plasma contains clotting factors and nutrients and usually makes up a little over half of a patient's blood volume. Patients may need transfusions because they have bleeding disorders, are actively bleeding and are at risk of hemorrhage, or are at risk of severe bleeding during surgery and other invasive procedures. Hospitals maintain stores of blood as well as contracts with blood banks to make plasma and other blood products available to patients as necessary.
Sources of plasma for transfusion vary. Donors may offer whole blood, allowing a blood bank to process the blood and separate out components. Transfusions of blood products, rather than entire units of whole blood, are very common. Donors can also undergo a procedure called plasmapheresis, where a machine separates plasma from other blood products, retaining the plasma and putting the rest of the blood back into the patient's body. Some patients may donate their own blood products to prepare for surgery and other needs. This allows a doctor to perform an autologous plasma transfusion with the donation the patient banked ahead of time.
In a plasma transfusion, a doctor orders an appropriate amount of plasma for the patient's needs. The blood bank freezes this blood component to keep it stable, and regularly thaws units to make sure supplies at an appropriate temperature will be available. Doctors may request plasma before, during, and after surgery to help the patient's blood clot more quickly, as the plasma increases the number of clotting factors. Other blood products like packed platelets are also available.
People with deficiencies in clotting factors due to hereditary conditions or temporary health problems may receive periodic plasma transfusion treatments. This will help the patient's blood clot more reliably, eliminating complications associated with excessive bleeding like damage to the joints and anemia. A patient in active hemorrhage because of injuries or surgery may also receive a plasma transfusion as part of treatment.
Any plasma used in a transfusion is carefully screened by blood bank employees to make sure it does not contain pathogens and is safe for use in patients. This process is highly reliable, with very low margins of error at most blood banks. Plasma transfusions are generally very safe and can be lifesaving for patients. The process of donation also comes with very limited risks, as nurses make sure people can safely donate before taking blood or any blood products and provide aftercare to make sure people are feeling well after donation is complete.