Lecture 20 - Practical Aspects of Blood Transfusion

Question 1

Aims of pre transfusion testing?

Answer 1

provide RBC for transfusion that will survive normally in recipients circulation, and avoid haemolytic tranfusion reactions

Question 2

Steps in ensuring safe transfusionn?

Answer 2

correct patient, ABORh typing, handwritten sample labelling, antibody screen, compatibility test, final bedside identity check

Question 3

Steps of pre-transfusion testing?

Answer 3

ABO Rh typing, antibody screen (Anti-human Globulin Technique) and blood component selection

Question 4

Group and screen?

Answer 4

situations when blood requirement risk is low e.g. surgery, antibody screen should be negative, serum retained in lab 7 days, available immediately on request

Question 5

3 compatibility tests?

Answer 5

Full cross match (usually only if antibody positive), immediate spin crossmatch (ABO msimatch) and computer crossmatch

Question 6

Criteria of final bedside check?

Answer 6

full name DOB, NHI, blood group

Question 7

Monitoring of transfusion?

Answer 7

major problems give early symptoms - stop the transfusion, maintain the line w saline and seek advice

Question 8

Acute transfusion reactions - differential diagnosis?

Answer 8

bacterial sepsis, immediate haemolytic transfusion reaction, anaphylaxis, circulatory overload, febrile non-haemolytic transfusion reactions

Question 9

Bacterial sepcosis?

Answer 9

contamination of blood component w endotoxin releasing bacteria, sudden onset hypotensive shock, severe progression - more likely in platelets kept at room temp therefore cultured

Question 10

Immediate haemolytic reaction?

Answer 10

rare, ABO incompatibility, renal failure, hypotension and disseminated intravascular coagulation, 10% fatal

Question 11

Extravascular Haemolytic reactions?

Answer 11

IgG presence in plasma and early phase complement activation

Question 12

Delayed Haemolytic transfusion reaction?

Answer 12

Hb fall and jaundice week after, casued by anamnestic antibody response (previous transfusions, pregnancy, non-detected)

Question 13

Febrile Non Haemolytic Transfusion Reactions?

Answer 13

common, occur in response to biological resposne modifiers accumulating in blood sample, reduced with leucodepletion

Question 14

Transfusion related Acute Lung Injury?

Answer 14

transfusion of donor plasma containing neutrophil/HLA antibodies causing agglutination in pulmonary vasculature, prevented using male plasma only and HLA antibody testing

Question 15

Transfusion related circulatory overload - those at risk?

Answer 15

compromised CVS, renal failure, congestive heart failure, transfusion volume too large for intravascular volume

Question 16

Allergic reactions?

Answer 16

urticarial - common, slow down transfusion and give anti-histamine; Anaphylaxis - rare, severe, hypotension and dyspnoea, IgA antibody in those w IgA deficiency

Question 17

Sources of transfusion error?

Answer 17

wrong patient wrong sample, laboratory procedures, blood issuing and collecting, wrong blood wrong patient