CPB Circuit Assembly & Priming Flashcards

Which CPB circuit component is specifically designed to remove leukocytes from the perfusate to reduce inflammatory responses?

Answer: Leukocyte depletion filter (LDF)

Leukocyte depletion filters selectively remove activated white blood cells from the perfusate, potentially reducing the systemic inflammatory response to CPB.

The purpose of the cardiotomy reservoir in a CPB circuit is to:

Answer: Collect shed mediastinal blood from surgical suction for reinfusion

The cardiotomy reservoir collects blood aspirated from the surgical field via suction, filters it, and returns it to the venous reservoir for recirculation.

When priming a CPB circuit, what is the recommended sequence for removing air from the oxygenator?

Answer: Fill from the venous blood inlet upward, allowing air to vent from the arterial outlet

Priming flows upward from the venous blood inlet allows trapped air to be pushed toward and out through the highest point (arterial outlet) of the oxygenator.

A perfusionist uses Plasmalyte-A as the primary crystalloid prime component. Compared to normal saline (0.9% NaCl), Plasmalyte-A offers which advantage?

Answer: Balanced electrolyte composition that reduces hyperchloremic acidosis risk

Plasmalyte-A is an isotonic, balanced crystalloid with chloride levels closer to plasma, reducing the risk of hyperchloremic metabolic acidosis seen with large volumes of normal saline.

Which factor most significantly affects the gas transfer efficiency of a membrane oxygenator during CPB?

Answer: The ratio of blood flow to membrane surface area (blood-side resistance)

Gas transfer efficiency depends heavily on blood-side resistance; an appropriate sweep gas-to-blood flow ratio and adequate membrane surface area are critical for optimal O2 delivery and CO2 removal.

Which precaution is most important when incorporating a cell saver (autotransfusion device) into the CPB circuit setup?

Answer: Preventing heparinized blood from being washed before adequate anticoagulation is confirmed

Cell-saved blood must not be washed and returned before confirming adequate systemic anticoagulation, as the wash process removes heparin and returns concentrated red cells.

During CPB circuit assembly, which step must be completed to ensure the heat exchanger functions safely for both warming and cooling?

Answer: Verifying the water-side circuit is free of leaks and connected to the temperature-controlled water source

A leak in the water circuit could introduce water into the blood path, causing hemolysis or air embolism; confirming the water circuit integrity and water source connection is essential before use.