CCP Cardiopulmonary Physiology & Pathophysiology 2

Question 1

Which parameter best describes the relationship between pulmonary capillary wedge pressure and left ventricular preload?

Accepted Answer

PCWP approximates left atrial pressure and thus left ventricular preload

Answer

Pulmonary capillary wedge pressure approximates left atrial pressure, providing an indirect measure of left ventricular preload.

Question 2

During cardiopulmonary bypass, a patient develops significant metabolic acidosis. Which compensatory mechanism would the perfusionist expect?

Accepted Answer

Increased ventilation to blow off CO2 and raise pH

Answer

Respiratory compensation for metabolic acidosis involves hyperventilation to reduce PaCO2 and raise blood pH.

Question 3

What is the primary determinant of pulmonary vascular resistance in a patient with hypoxic pulmonary vasoconstriction?

Accepted Answer

Alveolar hypoxia triggering smooth muscle contraction

Answer

Alveolar hypoxia triggers smooth muscle contraction in pulmonary arterioles, the hallmark mechanism of hypoxic pulmonary vasoconstriction.

Question 4

A perfusionist notes the arterial waveform shows pulsus paradoxus. Which condition is most consistent with this finding?

Accepted Answer

Cardiac tamponade

Answer

Cardiac tamponade causes pulsus paradoxus due to pericardial pressure limiting right heart filling and exaggerating inspiratory BP drop.

Question 5

Which factor has the greatest impact on myocardial oxygen consumption during cardiac surgery?

Accepted Answer

Heart rate and wall tension (preload/afterload)

Answer

Myocardial oxygen consumption is primarily determined by heart rate, wall stress (related to preload and afterload), and contractility.

(CCP) Certified Clinical Perfusionist Practice Test