ACE question: In a cardiopulmonary bypass circuit, blood drains from the right side of the heart into the venous drainage reservoir. Blood leaving the reservoir next encounters which component of the heart–lung machine?

  • (A) The aortic cannula
  • (B) The cardiopulmonary bypass pump
  • (C) The oxygenator
  • (D) The cardioplegia delivery pump
For a patient who is on full cardiopulmonary bypass (CPB), systemic venous blood flows from the vena cavae into the venous drainage cannulas, and then flows into the CPB venous reservoir. Blood is drawn from the CPB venous reservoir into the CPB pump, where the pump is used to develop enough forward pressure to drive blood through the CPB oxygenator. Oxygenated blood leaving the CPB oxygenator then flows into the arterial cannula and from there, enters the patient’s systemic arterial circulation (Figure 1). The cardioplegia delivery pump is typically separate from the patient CPB circuit.
Figure 1. Blood flow during full cardiopulmonary bypass. © 2016 American Society of Anesthesiologists.

Figure 1. Blood flow during full cardiopulmonary bypass. © 2016 American Society of Anesthesiologists.

Bibliography:
Martinez G, Whitbread J . Cardiopulmonary bypass. Anaesth Intensive Care Med. 2012;13(10):482-487.
Grocott HP, Stafford-Smith M, Mora-Mangano CT . Cardiopulmonary bypass management and organ protection. In: Kaplan JA, Augoustides JGT, Manecke GRJr, Maus T, Reich DL , eds. Kaplan’s Cardiac Anesthesia for Cardiac and Noncardiac Surgery. 7th ed. Philadelphia, PA: Elsevier Saunders; 2017:1111-1161.

Answer: B

Leave a Reply

Your email address will not be published. Required fields are marked *