CCS Hemostasis and Coagulation Management 1 — Questions and Answers
Question 1: What is the target activated clotting time (ACT) required before initiating cardiopulmonary bypass (CPB)?
- Greater than 300 seconds
- Greater than 480 seconds (Correct answer)
- Greater than 200 seconds
- Greater than 150 seconds
Correct answer: Greater than 480 seconds
An ACT greater than 480 seconds is required before CPB to ensure adequate anticoagulation and prevent clot formation in the circuit.
Question 2: Which anticoagulant is the standard of care for anticoagulation during cardiopulmonary bypass?
- Warfarin
- Bivalirudin
- Heparin (Correct answer)
- Fondaparinux
Correct answer: Heparin
Unfractionated heparin is the standard anticoagulant for CPB because its effect can be rapidly reversed with protamine sulfate and is easily monitored via ACT.
Question 3: What is the standard initial heparin dose given before cardiopulmonary bypass in cardiac surgery?
- 100 units/kg
- 300 units/kg (Correct answer)
- 500 units/kg
- 50 units/kg
Correct answer: 300 units/kg
300 units/kg of unfractionated heparin is the standard initial dose to achieve adequate anticoagulation for CPB.
Question 4: Which drug is used to reverse heparin anticoagulation at the conclusion of cardiopulmonary bypass?
- Vitamin K
- Fresh frozen plasma
- Protamine sulfate (Correct answer)
- Tranexamic acid
Correct answer: Protamine sulfate
Protamine sulfate neutralizes heparin by forming a stable complex, effectively reversing anticoagulation at the end of CPB.
Question 5: A patient on chronic warfarin therapy requires emergent cardiac surgery. What is the most appropriate immediate intervention to reverse anticoagulation?
- Administer protamine sulfate
- Give 4-factor prothrombin complex concentrate (4F-PCC) (Correct answer)
- Transfuse packed red blood cells
- Administer vitamin K alone
Correct answer: Give 4-factor prothrombin complex concentrate (4F-PCC)
4-factor PCC provides rapid reversal of warfarin by replacing clotting factors II, VII, IX, and X, which is critical in emergency settings when there is no time for vitamin K to take effect.
Question 6: Which coagulation test best monitors heparin anticoagulation during cardiopulmonary bypass?
- Prothrombin time (PT)
- Activated partial thromboplastin time (aPTT)
- Activated clotting time (ACT) (Correct answer)
- Thromboelastography (TEG)
Correct answer: Activated clotting time (ACT)
The ACT is used intraoperatively during CPB because it can be performed at the bedside with whole blood and provides rapid results within the range needed for high-dose heparin monitoring.
Question 7: Heparin resistance during cardiac surgery is most commonly associated with which condition?
- Factor V Leiden mutation
- Antithrombin III deficiency (Correct answer)
- Protein C deficiency
- Von Willebrand disease
Correct answer: Antithrombin III deficiency
Antithrombin III (AT III) deficiency causes heparin resistance because heparin exerts its anticoagulant effect primarily by binding and activating AT III to inhibit thrombin and factor Xa.
CCS Hemostasis and Coagulation Management 1
What is the target activated clotting time (ACT) required before initiating cardiopulmonary bypass (CPB)?