Blood groups and transfusions Flashcards
State the three responses to blood loss
Vasoconstriction,
Platelet plug formation,
Coagulation.
What is erythropoiesis
Production of RBC
What is the response of the SNS to significant blood loss
Increase rate and depth of heart contraction, vein constriction.
Adrenaline production
Define antigen
Any substance that is recognised as foreign and stimulates an immune response
What are the four blood groups
A, B, AB, O
for each group, state the antibody present in plasma
A=B
B=A
AB= null
O=A+B
State the universal recipient, and why
AB positive,
No antibodies present in plasma.
State the universal donor, and why
O negative,
No antigens present on RBC
What is blood typing
Identifying an individuals blood type
What is cross-matching
Mixing donor and recipient blood to measure compatibility
List the six different types of transfusion reactions
Acute haemolytic,
Febrile,
Mild allergic,
Anaphylactic,
Circulatory overload,
Sepsis.
State the two major physiological events that occur during an acute heamolytic reaction
Agglutination,
Haemolysis.
What is agglutination
Clumping of RBC which causes clots-
Can block vessels and cause renal failure.
What is haemolysis
Rupturing of RBC- causes contents to circulate.
Hb & K+
What causes a febrile reaction?
Sensitivity to donated leucocytes, platelets or plasma proteins
State the signs of an individual experiencing circulatory overload
Cough, hypertension, dyspnoea
Why is an acute heamolytic reaction severe
Excess production of antibodies,
Can cause obstruction due to agglutination and lead to heart arrhythmia
What is meant by Rhesus positive/negative
An individual with antigen D either present or not on their RBC.
