COMPLICATIONS OF BLOOD TRANSFUSION
 

• Serious complications of blood transfusion should be reported on a voluntary basis to the Serious Hazards of Transfusion (SHOT) enquiry which publishes a report yearly.

Immunological
 

Haemolytic transfusion reactions

• Due to ABO incompatibility.
• Associated with rigors, loin pain, SOB, hypotension, haemoglobinuria, renal failure, DIC

Delayed transfusion reaction

• Due to extra-vascular haemolysis presenting with anaemia and jaundice about 1 week after transfusion

Non-haemolytic febrile reaction

• Common and due to leukocyte antibodies.
• Associated with flushing, fever, tachycardia, rigors.

Urticaria & anaphylaxis

• Common and managed by stopping or slowing transfusion with use of anti-histamines. Severe anaphylaxis is rare

Allo-immunisation

• Due to antigens present on red cells, platelets, leukocytes, plasma.
• Not a problem with first transfusion but problems may arise with subsequent transfusions.
• Delayed consequences include haemolytic disease of the newborn and rejection of tissue transplants

Non-immunological
 

Transmission of infection

• Include Hep B or C,  HIV, CMV and EBV amongst others.
• Clotting factor concentrates are treated to inactivate viruses.
• Spirocheates do not survive for more than 72h in blood stored at 4C
• Bacterial contamination of blood components is a recognised cause of transfusion-associated death
• Risk of vCJD transmission likely to be very small

Transfusion-related acute lung injury (TRALI)

• TRALI is a severe acute reaction characterised by respiratory distress, hypoxia and pulmonary infiltrates soon after transfusion with no other apparent cause The reported incidence is 0.001 to 0.16% per patient transfused.
• It is the second commonest cause of transfusion-related major morbidity and mortality after ABO incompatibility in the UK
• Particularly likely to occur following transfusion of blood fractions with a large volume of plasma such as FFP.
• Pathogenetic mechanism of TRALI is unknown.
• TRALI is clinically indistinguishable from ARDS. However, TRALI is self-limiting, and there is usually clinical improvement within 48-96 hours provided prompt respiratory support is provided.
• No specific laboratory tests are available for TRALI and initial diagnosis depends on a high degree of clinical suspicion

Oxygen Affinity Changes

• Massive transfusion of stored blood with high oxygen affinity (due to low 2,3 DPG levels) may adversely affects oxygen delivery to the tissues. Use fairly fresh red cell transfusions (<1 week old).
• 2,3 DPG levels rise rapidly following transfusion and normal oxygen affinity is usually restored in a few hours.
• DIC and electrolyte imbalance due to massive transfusion of stored blood

Hypocalcaemia

• Each unit of blood contains approximately 3g citrate, which binds ionised calcium. The healthy adult liver will metabolise 3g citrate every 5 minutes.
• Transfusion at rates higher than one unit every five minutes or impaired liver function may thus lead to citrate toxicity and hypocalcaemia.

Hyperkalaemia

• Plasma potassium concentration of stored blood increases during storage and may be over 30mmol/l.
• Hyperkalaemia associated with large amounts of blood given quickly.
• Hypokalaemia is more common as red cells begin active metabolism and take up potassium.

Hypothermia

• Leads to reduction in citrate and lactate metabolism (leading to hypocalcaemia and metabolic acidosis), increase in affinity of haemoglobin for oxygen, impairment of red cell deformability, platelet dysfunction and an increased tendency to cardiac dysrhythmias. Use blood warmers for large transfusions.

Other risks
 

• Volume over-load
• Air embolism
• Thrombophlebitis
• Transfusion-induced immuno-suppression - mechanism unknown

Risks associated with transfusion of allogeneic blood in the UK
 

• Transmission of HIV: Less than    1 in 3 million
• Transmission of Hep B or C:    1 in 2 million
• Infective shock:      1 in 2 million
• ABO incompatibility:     1 in 5 million
• Delayed haemolytic transfusion reaction:  1 in 500
• Post-transfusion purpura:    1 in 2 million
• Transfusion-related acute lung injury:   1 in 2 million
• Immunisation to red cell / HLA antigens:   1 in 100 – 1 in 20 with multiple transfusion

Serious Hazards Of Transfusion (SHOT) report 2009 Summary
 

• 1279 cases analysed
• 73 cases of major morbidity (excluding anti-D related potential for major morbidity)
• One death definitely related to transfusion (Pseudomonas infection)
• 12 deaths in which the transfusion reaction may have contributed

Incorrect blood component transfused (IBCT)

• 282 cases
• 14 ABO-incompatible red cell transfusions were given
• 10 resulting from bedside administration errors,
• 2 from wrong blood in tube phlebotomy errors
• 2 due to laboratory errors.
• There were no deaths caused directly by transfusion, but 3 patients died following reactions that were considered to have contributed to their deaths
• A total of 149 (53%) of IBCT cases resulted primarily from a laboratory error and 133 (47%) from clinical and ward-based errors.
• Properly carried out patient identification, and a complete bedside check, could have prevented the 40 blood administration errors, the 4 wrong blood in tube (WBIT) errors and at least 8 of the laboratory cases of wrong blood

Inappropriate and unnecessary transfusion (I&U)

• 92 cases
• Two patients died following over-transfusion
• 15 cases were paediatric
• The majority of cases relate to lack of knowledge and errors of judgement (often due to inexperience) in clinical staff

Handling and storage errors (HSE)

• 196 cases
• There was no mortality and no major morbidity
• 62 cases relating to inappropriate storage of components
• 69 cases relating to excessive time to transfuse
• Overall 43 (22%) of cases related to laboratory errors, while the majority (153, 78%) arose outside the laboratory and were the responsibility of clinical, portering and transport staff.
• All staff involved in the transfusion process must understand the basic storage requirements of blood components.

Anti-D related events

• 186 anti-D related events
• There was no known fetal mortality from omission of anti-D
• 1 neonate suffered HDN which had been missed due to an assumption that the anti-D detected was prophylactic, when it was in fact immune.
• 127 cases of potential major morbidity where anti-D had been omitted or given more than 72 hours after the event.
• Clinical causes accounted for 80% of the errors
• There must be full traceability for anti-D administered to patients. If it has been given late or omitted for a woman of childbearing potential, the recipient should be followed up actively to check for formation of immune anti-D.

Acute transfusion reaction (ATR)

• 400 cases
• No direct deaths occurred
• 1 death in which the transfusion reaction possibly contributed
• 27 cases of major morbidity, the majority (17) being anaphylactic reactions.
• It is essential that moderate or severe reactions are properly investigated, and the possibility of bacterial contamination considered and acted on appropriately

Haemolytic transfusion reaction (HTR)

• 47 cases
• 8 acute and 39 delayed HTR
• There were no deaths
• There were 3 cases of major morbidity from acute and 5 cases from delayed HTR

Transfusion-related acute lung injury (TRALI)

• 21 cases
• 1 patient death was probably related, and 1 possibly related to TRALI.
• Eighteen patients were treated in ITU
• Antibodies concordant with HLA antigens in recipients were found in 8 donors, all female
• The components implicated were FFP (2 cases), platelet pools (3 cases), red cells in OA (3 cases, one of whom also received cryoprecipitate).
• This reinforces the absolute requirement for provision of 100% male plasma for FFP and for suspension of platelet pools across all the UK blood services

Transfusion-associated circulatory overload (TACO)

• 34 cases
• No direct deaths
• 2 deaths probably related and 2 possibly related.
• 9 cases of major morbidity in which the patient was transferred to ITU
• TACO is a relatively common complication of transfusion especially in the elderly and those with additional risk factors.
• Clinicians should be aware of the possibility of TACO, and its risk factors, and know how to minimise the chance of its occurrence bearing in mind also the appropriateness of the decision to transfuse

Transfusion-associated dyspnoea (TAD)

• 4 cases
• No mortality or major morbidity.

Post-transfusion purpura (PTP)
 

• There were no cases of PTP reported in 2009.

Transfusion-associated graft-versus-host disease (TA-GvHD)

• No cases of TA-GvHD have been reported in 2009, nor any since 2000–2001. However, 2 cases occurred following transfusion of leucodepleted components (in 1998–99 and 2000–01). The absence of new cases must not be allowed to justify a relaxation of local practice in relation to provision of irradiated components. Irradiated components are
• administered to over 300,000 susceptible patients each year, and it is a highly effective method of preventing this universally fatal complication.

Transfusion-transmitted infection (TTI)

• 3 cases
• Expired apheresis platelet pack contaminated with Streptococcus pneumoniae
• Red cells contaminated with Pseudomonas koreensis. The patient developed a pyrexia of and died the following day of transfusion-transmitted sepsis.
• Patients developing moderate or severe pyrexia following blood component transfusion must be suspected of having bacterial sepsis, and be investigated and treated appropriately.

Autologous transfusion

• 14 cases
• 6 relating to intraoperative cell salvage and 8 to postoperative cell salvage
• Five adverse reactions were reported to postoperative, unwashed autologous transfusion, including pyrexia, rigor and bradycardia.
• There were 3 cases of hypotensive reaction related to re-infusion of intraoperatively salvaged blood.