Haematology - Physiology Flashcards
What is the blood group of an individual with the A antigen on red blood cells and B antibody in plasma?
Group A
What is the blood group of an individual with the B antigen on red blood cells and A antibody in plasma?
Group B
What is the blood group of an individual with both A and B antigens on red blood cells?
Group AB (universal recipient)
What is the blood group of an individual with neither A nor B antigens on red blood cells and both A and B antibodies in plasma?
Group O (universal donor)
What is the blood type of an individual who is a universal recipient of blood cells?
Blood group AB; A and B antigen on red blood cells
What is the blood type of an individual who is a universal donor of blood products?
Blood group O; neither A nor B antigens on red blood cells
A patient receiving a blood transfusion suddenly develops symptoms of anaphylaxis, renal failure, and hypotension and has schistocytes on a smear; what is the likely cause?
Incompatible blood type transfusion
What happens when an Rh-negative mother is exposed to Rh-positive blood (for instance, during delivery)?
Exposure to Rh-positive blood (which has the Rho antigen) will result in the development of anti-Rh immunoglobulin G antibodies, which may complicate future pregnancies
Which class of antibodies are produced against the ABO blood groups?
Immunoglobulin M
Which class of antibodies are produced against Rh factor?
Immunoglobulin G
If a mother is blood type O and her fetus is blood type B, will the fetus be at risk for hemolytic disease of the newborn?
No; antibodies against ABO blood groups are immunoglobulin M class and do not cross the placenta
What happens when an Rh-negative mother with anti-Rh antibodies becomes pregnant with a child who is Rh positive?
Erythoblastosis fetalis; the anti-Rh immunoglobulin G crosses the placenta and causes hemolysis in the newborn
What part of the fibrinolytic system also activates the complement cascade by cleaving C3 to C3a?
Plasmin
Kallikrein links the coagulation cascade to the kinin cascade through its activation of _____ and to the fibrinolytic system through its activation of _____.
Bradykinin; plasminogen (to plasmin)
Name two reactions initiated by high-molecular-weight kininogen.
High-molecular-weight kininogen is the initial reagent in the kinin cascade and stimulates the coagulation cascade by interacting with factor XII
What does plasmin create when it interacts with fibrin clots?
Fibrin split products (fibrin degradation)
Once high-molecular-weight kininogen cleaves to form bradykinin, what are the effects of the kinin cascade?
Vasodilation, vascular permeability, and pain
What factor converts prokallikrein to kallikrein and factor XI to XIa?
Factor XIIa; it is thus involved in both the kinin cascade and the coagulation cascade
Which coagulation factors are specific to the intrinsic coagulation pathway?
Factor XII, factor XI, factor IX, and factor VIII
Which coagulation factors are specific to the extrinsic coagulation pathway?
Factor VII and tissue factor (thromboplastin)
Which coagulation factors are common to both the intrinsic and extrinsic coagulation pathways?
Factor X, factor V, factor II (prothrombin), and factor XIII
What is the end result of the coagulation cascade?
The conversion of fibrinogen into fibrin to form a fibrin mesh that will stabilize the platelet plug