TBL Questions Flashcards
A 22 year old man sustains an injury knee playing football and develops bruising and swelling of his knee and leg. How do circulating platelets stick to the damaged vessel wall during primary haemostasis?
Platelets have glycoprotein receptors through which they are able to bind to the damaged vessel wall.
A 22 year old man sustains an injury knee playing football and develops bruising and swelling of his knee and leg. How does tissue factor (TF) contribute to blood coagulation?
By binding to factor VIIa and activating factors IX and X.
A 22 year old man sustains an injury knee playing football and develops bruising and swelling of his knee and leg. What role does calcium play in haemostasis?
Calcium helps clotting factors bind to the phospholipid surfaces of platelets.
A 22 year old man sustains an injury knee playing football and develops bruising and swelling of his knee and leg. What happens after thrombin generation has taken place?
Further thrombin generation is limited by the actions of protein C.
A 22 year old man sustains an injury knee playing football and develops bruising and swelling of his knee and leg. His symptoms persist and he is found to have a ligament injury that requires surgery. Bleeding during the operation is greater than expected and tranexamic acid is administered. What is the effect of tranexamic acid on haemostasis?
Fibrinolytic activity is reduced.
A 22 year old man sustains an injury knee playing football and develops bruising and swelling of his knee and leg. His symptoms persist and he is found to have a ligament injury that requires surgery. Bleeding during the operation is greater than expected and tranexamic acid is administered. In light of the bleeding it is decided not to give heparin after the surgery as per usual practice. What is the effect of heparin on haemostasis?
Anticoagulant activity is increased.
A 22 year old man sustains an injury knee playing football and develops bruising and swelling of his knee and leg.
His symptoms persist and he is found to have a ligament injury that requires surgery.
Bleeding during the operation is greater than expected and tranexamic acid is administered.
In light of the excess bleeding it is decided to perform a coagulation screen. The first data set is shown in the table below.
How would you interpret these findings?
His prothrombin time result confirms normal Factor X activity.
A 22 year old man sustains an injury knee playing football and develops bruising and swelling of his knee and leg.
His symptoms persist and he is found to have a ligament injury that requires surgery
Bleeding during the operation is greater than expected and tranexamicacid is administered.
In light of the excess bleeding it is decided to perform a coagulation screen. The second data set is shown in the table below.
How would you interpret these findings?
The APTT result is consistent with a diagnosis of Factor VIII deficiency.
A 22 year old man sustains an injury knee playing football and develops bruising and swelling of his knee and leg
His symptoms persist and he is found to have a ligament injury that requires surgery
Bleeding during the operation is greater than expected and tranexamic acid is administered. Coagulation tests are performed.
Following the results of the coagulation tests the consultant asks for his liver function to be assessed.
Why is a test of liver function useful?
Most coagulation factors are produced in the liver
A 22 year old man sustains an injury knee playing football and develops bruising and swelling of his knee and leg
His symptoms persist and he is found to have a ligament injury that requires surgery
Bleeding during the operation is greater than expected and tranexamicacid is administered. Coagulation tests are performed.
The patient is subsequently advised to avoid painkillers that contain aspirin. Why is this?
Aspirin irreversibly inhibits platelet activation.
Why can a transfusion of blood (red cells) of the wrong ABO group to a patient, be fatal?
The patient has anti-A or anti-B antibodies in their plasma, which activate complement fully, to haemolyse the red cells.
She needs blood (red cells) within 5 minutes, so there is not time to test her blood group. Which blood should we give in an emergency?
O negative.
Which blood component will she need to replace all her coagulation factors (as depleted following massive bleeding, and there is very little present in stored red cells)?
Fresh Frozen Plasma
For this blood component (FFP), which group should we give in an emergency?
O
While she receives emergency transfusion, which tests will be needed to provide fully compatible blood for her?
ABO & RhD group and antibody screen.
