CCP CCP Blood Conservation & Transfusion Strategies 2 — Questions and Answers
Question 1: Conventional ultrafiltration (CUF) performed during CPB is used to:
- Remove excess air from the arterial line
- Remove excess fluid and hemoconcentrate the patient during bypass (Correct answer)
- Filter microemboli from the venous reservoir
- Measure real-time urine output
Correct answer: Remove excess fluid and hemoconcentrate the patient during bypass
CUF removes excess water and small solutes across a semipermeable membrane during CPB, helping manage volume balance and hemoconcentrate the patient.
Question 2: Which coagulation factor is most rapidly depleted during CPB due to hemodilution and consumption?
- Factor VIII
- Fibrinogen (Correct answer)
- Factor X
- Protein C
Correct answer: Fibrinogen
Fibrinogen is highly susceptible to dilutional loss and CPB-induced consumption, and its depletion is a major contributor to post-bypass coagulopathy.
Question 3: Platelet dysfunction after CPB is primarily caused by:
- Heparin directly binding and inhibiting platelets
- Platelet activation and degranulation from contact with CPB circuit surfaces (Correct answer)
- Hypothermia-induced thrombocytosis
- Excess protamine administration
Correct answer: Platelet activation and degranulation from contact with CPB circuit surfaces
Contact of platelets with the artificial surfaces of the CPB circuit causes activation, degranulation, and a qualitative functional defect even when platelet counts remain adequate.
Question 4: Desmopressin (DDAVP) is used in cardiac surgery primarily to:
- Reverse heparin anticoagulation after bypass
- Release endogenous von Willebrand factor and factor VIII to improve platelet function (Correct answer)
- Stimulate red blood cell production
- Prevent systemic fibrinolysis
Correct answer: Release endogenous von Willebrand factor and factor VIII to improve platelet function
DDAVP stimulates endothelial release of stored von Willebrand factor and factor VIII, improving platelet adhesion especially in patients with qualitative platelet dysfunction.
Question 5: A bloodless surgery program for Jehovah's Witness patients primarily relies on:
- Artificial hemoglobin-based oxygen carriers as substitutes
- Preoperative optimization, cell salvage, and volume expanders to avoid allogeneic transfusion (Correct answer)
- Performing surgery under local anesthesia to reduce blood loss
- Postoperative erythropoietin only
Correct answer: Preoperative optimization, cell salvage, and volume expanders to avoid allogeneic transfusion
Bloodless surgery programs combine preoperative erythropoietin/iron therapy, intraoperative cell salvage, meticulous hemostasis, and volume expanders to avoid all allogeneic blood products.
Question 6: Thromboelastography (TEG) or rotational thromboelastometry (ROTEM) measures:
- Platelet count only
- Whole blood viscoelastic clot formation, strength, and fibrinolysis in real time (Correct answer)
- PT and aPTT simultaneously from plasma
- Fibrinogen concentration by immunoassay
Correct answer: Whole blood viscoelastic clot formation, strength, and fibrinolysis in real time
TEG/ROTEM assesses viscoelastic properties of whole blood from clot initiation through fibrinolysis, enabling goal-directed transfusion therapy after CPB.
CCP CCP Blood Conservation & Transfusion Strategies 2
Conventional ultrafiltration (CUF) performed during CPB is used to: