Blood transfusion

Last updated: Saturday, 13, November, 2010


Key InformationAppropriate Tests
Donor testing

Donor suitability is determined initially by questionnaire ± interview. Blood group, blood group antibody screen; haemoglobin; hepatitis B virus testing (HBsAg), hepatitis C virus testing (HCV antibody); HIV antibodies (HIV-1 and HIV-2); syphilis testing - serum; HTLV-I antibodies and HTLV-II antibodies. The same testing is required for donors of autologous and directed blood transfusions. Cytomegalovirus antibodies if blood is being collected for recipients at high risk of CMV infection eg neonates, patients with bone marrow or organ transplants.

Recipient testing

Meticulous attention to patient identification and specimen labelling is required. (See current Guidelines for pretransfusion testing, ANZSBT)

Blood group, blood group antibody screen, compatibility testing (cross-match) against group compatible donor cells. See


Allergic reaction 

1-3% of plasma infusions.

Urticaria and hives in absence of other symptoms or signs.

Anaphylactioid or anaphylactic reactions 

1:20 000-70 000

See also Anaphylaxis.

  • Offending antigen may be
  • Blood component protein 

Immunoglobulins G, A, M; consider possibility of selective IgA deficiency in recipient - anti IgA antibodies.

  • Ingestants in donor plasma

Ingested substances (eg drugs, food, chemicals) present in donor plasma may cause adverse reactions in the recipient. Skin prick allergen testing and/or allergen specific immunoglobulin E in recipient, as indicated from history.

Febrile nonhaemolytic transfusion reactions 

Most common reaction.Can be caused by recipient antibodies or by presence of bioreactive substances. Rxleucocyte depleted products.

Circulatory overload 

Up to 1% of patients

Delayed haemolytic transfusion reaction


Usually due to previous sensitisation to red cell antigens (eg, prior transfusion, pregnancy); the antibody may be at low titre and undetectable in the initial blood group antibody screen.

Usually occurs 4-14 days post transfusion.

FBC, blood film, reticulocyte count; direct antiglobulin test.

Repeat blood group antibody screen on pre- (if available) and post-transfusion serum. Bilirubin, LD, haptoglobin.

Transfusion-related acute lung injury (TRALI) 

1:5000-10 000

Diagnosis is clinical. Presents with respiratory distress, tachycardia and fever, hypotaxia. CXR shows a "white out" with diffuse alveolar and interstitial infiltrates.

Usually due to leucoagglutinating or HLA specific antibodies in transfused plasma. HLA antibodies (donor); HLA typing (recipient).

ABO incompatibility

 ~1:12 000-77 000

Cease transfusion immediately; resuscitate and investigate. Check patient's identity against the identification information on the blood pack and transfusion form. Return blood pack and giving set to laboratory with 10 mL clotted blood from patient for repeat blood group, blood group antibody screen, compatibility testing. The blood group, antibody screen and compatibility testing are also repeated on the pre-transfusion sample. Also, collect blood for FBC, blood film, direct antiglobulin test, haptoglobin, Schumm's test.  Collect the first urine passed for haemoglobin - urine. See also DIC

A similar clinical syndrome may result from microbial contamination of a blood unit: see below.

Graft versus host disease 

Due to engraftment and proliferation of allogeneic T lymphocytes: HLA typing on donor and recipient. Typically occurs in severely immunocompromised individuals (eg after blood/marrow stem cell transplant), but has been reported after directed donations from relatives in immunocompetent recipients. Directed donations are routinely irradiated (minimum 25 Gy) before administration.

Post-transfusion purpura 


Profound thrombocytopenia approximately 1 week after transfusion. Platelet antigen typing, platelet antibodies (recipient).

Bleeding during transfusion

Immediate haemolytic transfusion reaction. Bacterial contamination of blood unit 

Excessive bleeding may be an early sign of an ABO incompatible transfusion or of septicaemia from bacterial contamination of the transfused blood unit, especially in an anaesthetised patient.

See DIC.

  • Massive transfusion 
  • Bleeding

>10 units of packed cells in <24 hours in an adult.

Clinical severity of bleeding is often more than can be explained by dilution of platelets and coagulation factors: FBC (thrombocytopenia), PT, APTT.

Hypothermia is a common contributor to microvascular ooze and DIC.

Hyperkalaemia, hypokalaemia

Hyperkalaemia is commonly due to acidosis rather than to rate of transfusion.



Citrate toxicity is rarely a serious problem except with very rapid rates of transfusion: ionised calcium - plasma or serum; total calcium is misleading due to binding of calcium by citrate in transfused plasma. 

Transfusion transmitted infections 

  • Viral Infection

The figures below detail the estimated risk for the period July 2000 to June 2003. These estimates were provided by the Australian Red Cross Blood Service (ARCBS) in May 2005, and estimates are updated from time to time on the Australian Red Cross website.
Figures for 'HIV / HCV antibody testing only' are included to allow for risk comparison in the rare event that products are released without Nucleic Acid Testing (NAT).

  • Bacterial infection

~1:100 000 for platelets.

Platelet concentrates most frequently implicated. Blood culture collected from recipient and donor blood pack; see Septicaemia An immediate haemolytic transfusion reaction must be excluded.

Virus and testing standard:

Point estimate of residual risk 'per unit':

HIV 1 and 2 antibody only

1 in 2,404,000

HIV antibody + NAT

1 in 7,299,000

HCV antibody only

1 in 330,000

 HCV antibody + NAT

1 in 3,663,000


1 in 1,339,000

HTLV l and ll

Considerably less.

Iron overload 

Increasing risk with tranfusion of >20 units.