CVP Physiological and Pathophysiological Concepts 3

Question 1

During CPB, a patient with a known left ventricular aneurysm is at greatest risk for which perfusion-related complication?

Accepted Answer

Inadequate LV venting leading to ventricular distension

Answer

LV aneurysms impair contractility and ventricular ejection, increasing risk of inadequate venting and distension during CPB.

Question 2

The oxygen-hemoglobin dissociation curve shifts to the right in the presence of:

Accepted Answer

Acidosis, hyperthermia, and elevated 2,3-DPG

Answer

Acidosis, hyperthermia, and elevated 2,3-DPG all decrease hemoglobin's affinity for oxygen, shifting the dissociation curve rightward (Bohr effect).

Question 3

Which pathophysiologic mechanism underlies the phenomenon of 'coronary steal' in patients with coronary artery disease during CPB?

Accepted Answer

Vasodilators preferentially dilate non-stenotic vessels, diverting flow from ischemic territories

Answer

Coronary steal occurs when vasodilators dilate normal vessels, reducing perfusion pressure distal to stenoses and diverting blood away from ischemic myocardium.

Question 4

In the context of cardiopulmonary bypass, which statement about the systemic inflammatory response syndrome (SIRS) is most accurate?

Accepted Answer

Contact of blood with the CPB circuit activates complement, cytokines, and neutrophils

Answer

Blood contact with artificial surfaces activates complement cascades, releases cytokines, and primes neutrophils, generating a SIRS response during CPB.

Question 5

A patient's arterial blood gas on CPB shows pH 7.30, PaCO2 55 mmHg, PaO2 320 mmHg. The perfusionist should first:

Accepted Answer

Increase sweep gas flow rate to remove excess CO2

Answer

Increasing sweep gas flow through the oxygenator enhances CO2 elimination, directly correcting the respiratory acidosis.

(CVP) Cardiovascular Perfusionist Practice Test

(CVP) Cardiovascular Perfusionist Practice Test

CVP Physiological and Pathophysiological Concepts 3