MAC Fluid Management & Blood Products 2 — Questions and Answers
Question 1: On thromboelastography (TEG), a prolonged R-time (reaction time) beyond the normal reference range indicates:
- Fibrinolysis
- Fibrinogen deficiency
- Clotting factor deficiency requiring FFP (Correct answer)
- Platelet dysfunction
Correct answer: Clotting factor deficiency requiring FFP
The TEG R-time represents the latency period for initial clot formation driven by enzymatic coagulation factors; a prolonged R-time indicates factor deficiency and is treated with fresh frozen plasma.
Question 2: Intraoperative cell salvage (autotransfusion) is CONTRAINDICATED in which of the following clinical situations?
- Total hip arthroplasty
- Hepatic resection for benign liver disease
- Ruptured abdominal aortic aneurysm repair
- Active bacterial contamination of the operative field (Correct answer)
Correct answer: Active bacterial contamination of the operative field
Cell salvage is contraindicated with bacterial contamination (e.g., bowel spillage) because reinfusing contaminated blood risks sepsis, and it is relatively contraindicated in malignancy due to potential cancer cell reinfusion.
Question 3: A patient who has received 10 units of pRBCs develops continued surgical bleeding with PT/aPTT > 1.5 times normal and platelet count of 85,000/μL. The most appropriate first-line treatment is:
- Protamine sulfate 50 mg IV
- Platelet transfusion 1 apheresis unit
- Fresh frozen plasma (FFP) 10-15 mL/kg (Correct answer)
- Recombinant activated Factor VIIa (rFVIIa)
Correct answer: Fresh frozen plasma (FFP) 10-15 mL/kg
Massively transfused patients develop dilutional coagulopathy with factor depletion reflected by prolonged PT/aPTT; FFP at 10-15 mL/kg provides multiple clotting factors and is the first-line treatment for this pattern.
Question 4: According to recent FDA hemovigilance reports, which is the LEADING cause of transfusion-related fatality in the United States?
- ABO incompatibility hemolytic reactions
- TRALI (transfusion-related acute lung injury)
- Bacterial sepsis from platelet transfusion
- TACO (transfusion-associated circulatory overload) (Correct answer)
Correct answer: TACO (transfusion-associated circulatory overload)
Since approximately 2016, TACO has surpassed TRALI as the leading reported cause of transfusion-related mortality in the US, partly due to improved TRALI mitigation through male-predominant plasma donation strategies.
Question 5: The minimum acceptable platelet count recommended before performing neuraxial anesthesia (spinal or epidural) in a non-emergent elective setting is:
- 20,000/μL
- 50,000/μL
- 80,000/μL (Correct answer)
- 150,000/μL
Correct answer: 80,000/μL
Most major anesthesiology societies recommend a minimum platelet count of 80,000/μL for elective neuraxial procedures to reduce the risk of epidural hematoma, although thresholds can be individualized.
Question 6: The most serious cardiovascular adverse reaction to rapid protamine sulfate administration following cardiopulmonary bypass is:
- Hyperkalemia and complete heart block
- Hypoglycemia and seizures
- Methemoglobinemia and cyanosis
- Severe systemic hypotension and acute pulmonary hypertension (Correct answer)
Correct answer: Severe systemic hypotension and acute pulmonary hypertension
Protamine can trigger IgE-mediated anaphylaxis (especially in NPH insulin users or fish-allergic patients) or complement activation, causing profound systemic hypotension and acute pulmonary hypertension that may lead to right ventricular failure.
Question 7: In a patient with chronic renal failure undergoing cardiac surgery, which blood product poses the greatest risk of causing life-threatening hyperkalemia?
- Freshly collected packed red blood cells (< 5 days old)
- Fresh frozen plasma
- Leukoreduced apheresis platelets
- Stored packed red blood cells (> 14 days old) (Correct answer)
Correct answer: Stored packed red blood cells (> 14 days old)
During storage, RBCs undergo progressive membrane ion pump failure with intracellular potassium leaking into the storage solution; older units (> 14 days) contain markedly elevated extracellular potassium that cannot be cleared by a failing kidney.
MAC Fluid Management & Blood Products 2
On thromboelastography (TEG), a prolonged R-time (reaction time) beyond the normal reference range indicates: