Complications of blood transfusion

v  The risks of transfusion must be weighed against the benefits.

v  Majority of side - effects are mild, the overall incidence of complications is estimated at 2 – 5%.

v  Immediate fatalities, although difficult to quantify accurately, are of the order of 1 in 100 000 to 1 in 500 000 patients transfused

v  50% of these are caused by ABO incompatibilities, mainly due to failure to correctly identify the donor or recipient at the time of sampling or at the time of transfusion.

Classification

The complications of blood transfusion can be conveniently divided into:

v  Acute and delayed.

·         Acute (<24 hours) Transfusion Reactions.

v  Immunological and non – immunological.

·         Delayed (>24 Hours) Transfusion Reaction.

Immediate (non- immune)

1.    Bacterial contamination:

v  Although uncommon, but this type of specific reaction can have a rapid onset and high mortality in recipients.

v  The presence of bacteria in transfused blood may lead either to febrile reactions in the recipient (due to pyrogens) or serious manifestations of septic or endotoxic shock.

v  Commonly caused by endotoxin produced by bacteria capable of growing in cold temperatures such as Pseudomonas species, E. coli, Yersinia enterocolitica.

v  Infection of stored blood is extremely rare.

v  Skin contaminants are not infrequently present in freshly donated blood but these organisms (predominantly staphylococci) do not survive storage at 4 º C although they will grow profusely in platelet concentrates stored at 22 º C.

v  Healthy donor who are bacteremic at the time of donation. The majority are due to Yersinia enterocolitica, which grows well in red cell components due to its dependence on citrate and Iron

v  Usually appear rapidly during transfusion or within about 30 minutes after transfusion with dryness, flushing of skin.

v  Fever, Hypotension, Chills, Muscle pain, vomiting, Abdominal cramps, Bloody diarrhoea, Hemoglobinuria, Shock, Renal failure, DIC.

Prevention:

v  Strict adherence to policies & procedures regarding blood component collection, storage, handling, and preparation is essential to reduce the risk.

v  Visual Inspection of components before release from the transfusion service includes any discoloration, visible clots, or hemolysis.

v  Ensure the blood components are infused within standard time limits (4 hours).

v  Blood packs should never be opened for sampling, if any open method of preparation has been used, the unit should be transfused within 24 hours.

v  Blood should always be kept in accurately controlled refrigerators (with alarms), maintained strictly at 2 – 6 º C, the blood should never be removed and taken to the ward or OT until it is required.

2.    Circulatory overload

v  Young people with normal cardiovascular function will tolerate volume changes after transfusion provided it is not excessive.

v  Patient with severe anemia, elderly with compromised cardiovascular function will not tolerate the increase in plasma volume and acute pulmonary edema may develop.

v  Packed cell should be used instead of whole blood.

v  Packed cells should be given slowly over 4 hours. The usual rate of transfusion is about 200 ml per hour. In patient at risk rate of 100 ml per hour or less are appropriate.

v  Diuretics should be given at the start of the transfusion and only one or two units of concentrated red cells should be transfused in any 24 hour period.

Prevention:

v  Blood transfusion should be given during the daytime, Overnight transfusion should be avoided wherever possible.

Immediate (immunological)

1.    Febrile non hemolytic reaction

v  An INCREASE in temperature of 1OC during infusion of blood component

v  Usually “mild & benign” = not life threatening

v  Can have more severe symptoms, not usually

v  Non-hemolytic

v  Cause: Recipient antibodies to donor WBCs & Cytokines in the transfused blood component.

v  Seen in: Multiply transfused patients, Multiple pregnancies and previously transplanted

Prevention:

v  Leukocyte reduction.

2.    Allergic (Urticarial-Hives)

v  Etiology: Form of cutaneous hypersensitivity triggered by recipient antibodies directed against:

v  Donor plasma proteins or

v  Other allergens in donor plasma

v  Begins within minutes of infusion

v  Characterized by rash and/or hives and itching.

v  Common (1 per 2000 transfusions).

v  Usually involves release of histamine.

Prevention:

v  Can pre-treat recipient with anti-histamines before transfusion.

3.    Anaphylaxis

v  Life threatening!!

v  Etiology:

v  Recipient is IgA deficient & has anti-IgA in serum

v  Recipient anti-IgA can react to even small amounts of donor IgA in the plasma in any blood component

v  Reaction may occur within minutes: Onset of symptoms is SUDDEN.

Prevention:

v  Wash cellular components or blood products from IgA deficient.

4.    Acute hemolytic transfusion reaction

v  Associated with Intravascular Hemolysis

v  Etiology: Antibodies that activate complements in the vasculature: ABO antibodies are predominant / not the only ones.

Prevention:

v  Give ABO compatible blood.

Acute hemolytic transfusion reaction

Characteristics	Signs
v  Within minutes v  IgM &/or IgG antibody v  Complement activation v  Release of histamine and serotonin	v  Pain along infusion site v  Shock v  DIC/Hemoglobinemia/uria v  fever, hypotension v  Renal failure

Delayed transfusion reactions:

v  Transfusion haemosiderosis (iron overload).

v  Disease transmission.

v  Post transfusion purpura.

v  Transfusion associated GvHD.

Transfusion haemosiderosis

v  A complication of repeated long term blood transfusion.

v  Most commonly seen in thalassaemic patient.

v  Each unit of blood has about 200 mg of iron, while the daily excretion rate is about 1 mg. The body has no way of excreting the excess unless the patient is bleeding.

v  Assessment of storage iron levels such as ferritin levels should be done.

Treatment

v  The use of Iron chelating agent.

Transmittable diseases:

v  Hepatitis (B,C).

v  Syphilis.

v  Malaria.

v  Cytomegalovirus.

v  Human immunodeficiency virus.

Donor selection criteria and subsequent screening of all. Donations are designed to prevent disease transmission, but these do not completely eliminate the hazards