CCP Perfusion Equipment & Technology Operation 3 — Questions and Answers
Question 1: Centrifugal blood pumps generate flow by:
- Compressing flexible tubing segments rhythmically
- Creating a rotating magnetic field that spins an impeller or cone (Correct answer)
- Applying pulsatile pneumatic pressure to a blood sac
- Using roller compression against a rigid housing
Correct answer: Creating a rotating magnetic field that spins an impeller or cone
Centrifugal pumps use a rotating impeller or cone driven magnetically to impart kinetic energy to blood, generating non-occlusive constrained vortex flow.
Question 2: A key safety advantage of centrifugal pumps over roller pumps during CPB is:
- They provide pulsatile flow more efficiently
- They cannot generate excessive negative or positive pressures that could cause tubing rupture or cavitation (Correct answer)
- They require no priming volume
- They eliminate the need for an arterial line filter
Correct answer: They cannot generate excessive negative or positive pressures that could cause tubing rupture or cavitation
Centrifugal pumps are non-occlusive and will stall rather than generate dangerously high pressures or extreme negative pressures that could rupture tubing or cause cavitation.
Question 3: Antegrade warm blood cardioplegia is delivered via the:
- Coronary sinus catheter
- Aortic root or direct coronary ostia (Correct answer)
- Pulmonary artery catheter
- Left ventricular vent
Correct answer: Aortic root or direct coronary ostia
Antegrade cardioplegia is delivered through the aortic root or directly into coronary ostia, following the normal direction of coronary blood flow.
Question 4: Modified ultrafiltration (MUF) performed after CPB primarily serves to:
- Replenish clotting factors lost during bypass
- Hemoconcentrate the patient and reduce the systemic inflammatory response (Correct answer)
- Reverse heparin anticoagulation
- Re-prime the circuit with crystalloid solution
Correct answer: Hemoconcentrate the patient and reduce the systemic inflammatory response
MUF removes excess fluid and inflammatory mediators accumulated during bypass, improving hematocrit and attenuating the systemic inflammatory response post-CPB.
Question 5: During retrograde cardioplegia delivery, the cannula is placed in the:
- Aortic root
- Coronary sinus (Correct answer)
- Left anterior descending artery
- Right internal mammary artery
Correct answer: Coronary sinus
Retrograde cardioplegia is delivered via a balloon-tipped catheter placed in the coronary sinus, allowing the solution to flow against the normal direction of coronary venous drainage.
Question 6: The sweep gas flow rate through the oxygenator primarily controls:
- Blood temperature during bypass
- Carbon dioxide removal and PaCO2 levels (Correct answer)
- Oxygen saturation of venous blood
- Pump flow rate
Correct answer: Carbon dioxide removal and PaCO2 levels
Increasing sweep gas flow enhances CO2 removal (ventilation effect), while oxygen content of the sweep gas determines oxygen transfer to blood.
Question 7: Which alarm would MOST urgently require the perfusionist to immediately cease CPB pump flow?
- Mild hypothermia alert
- Arterial line pressure high alarm with visible tubing distension distal to the pump (Correct answer)
- Venous reservoir high level alarm
- Minor fluctuation in sweep gas oxygen concentration
Correct answer: Arterial line pressure high alarm with visible tubing distension distal to the pump
A high arterial pressure alarm with distal tubing distension indicates potential aortic cannula obstruction or massive resistance, requiring immediate cessation of flow to prevent circuit rupture or aortic injury.
CCP Perfusion Equipment & Technology Operation 3
Centrifugal blood pumps generate flow by: