Guidelines / Advice

Risks of Blood Transfusions

Transfusion of blood or blood products involves the doctor in the evaluation of the risk/benefit ratio to the patient. All blood products carry a risk of adverse effects, ranging from sensitisation to donor cells or proteins, to transmission of disease, including HIV infection. The transfusion service endeavours to minimise major risks in the following manner:

Haemolytic Transfusion reactions

By crossmatch and compatibility testing and strict attention to details of patient name, number and identification procedures at point of issue. The medical practitioner ordering blood should ensure strict specimen identification of patient name, hospital number and folder and crossmatch protocol. See Administration of blood. Patients must be monitored at the start of the infusion and every 15 minutes thereafter. Transfusions should be stopped immediately should there be any untoward signs or reaction.

Transmissible diseases and donor selection:

Health screening

All donors are screened by means of a written questionnaire for evidence of any past or present infection that might be transmitted to the patient. This screening includes questions about behavioural patterns that may identify a risk of HIV and other infections. In addition the donor may be further questioned verbally prior to being selected for the donation process.

Testing

All donated units are screened for laboratory evidence of Syphilis, Hepatitis B and C, HIV 1 and 2. The tests used are internationally validated and are subject to stringent quality controls.

All reactive units are removed from quarantine and incinerated. Further confirmatory tests are performed to confirm reactivity and the donors subsequently notified and deferred.

Only units that are negative for the above markers are accepted for transfusion or for further processing.

Given the strict adherence to international standards of donor deferral and extremely sensitive test systems the risk of hidden infection is low, but recipients must be informed about the risk.

Look back programme

This programme was initiated in 1985 by the Blood Transfusion Services of South Africa to assess the incidence of transfusion transmitted infection.

This programme traces any patient who received HIV and Hepatitis negative blood from a donor whose subsequent donation is found positive for either infection. Patients are contacted through the hospital or their private physician and are offered counselling and testing. Contacting the recipient is obligatory and may help prevent secondary spread to others through sexual contact. Ultimately the doctor who ordered the blood transfusion is responsible for training, counselling and testing the recipient and for managing and treating the patient, or referring the patient to a specialist, where appropriate.

Additional safety measures

Where the applicable technology exists, the blood product is further treated to inactivate any latent infection.

Currently the following products undergo viral inactivation procedures: Albumin, Stabilised Serum, Factor VIII and IX concentrates, Intravenous Immunoglobulin's and Fresh Dried Plasma (FDP). While not all intramuscular immunoglobulin preparations undergo specific viral inactivation procedures, the manufacturing process appears to inactivate viruses and there have been no reports of viral transmissions of registered preparations in South Africa.

Plasma products such as Cryoprecipitate and Fresh Frozen Plasma (FFP) carry a similar risk to cellular products; however, a virally inactivated lyophilised FDP is produced by Natal Bioproducts Institute (NBI), while other Services are currently introducing a quarantined retested FFP to avoid window period infections.