Cardiopulmonary Physiology & Pathophysiology Flashcards
7 cards from real CCP practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Cardiopulmonary Physiology & Pathophysiology flashcards as text
Which parameter best describes the relationship between pulmonary capillary wedge pressure and left ventricular preload?
Answer: PCWP approximates left atrial pressure and thus left ventricular preload
Pulmonary capillary wedge pressure approximates left atrial pressure, providing an indirect measure of left ventricular preload.
During cardiopulmonary bypass, a patient develops significant metabolic acidosis. Which compensatory mechanism would the perfusionist expect?
Answer: Increased ventilation to blow off CO2 and raise pH
Respiratory compensation for metabolic acidosis involves hyperventilation to reduce PaCO2 and raise blood pH.
What is the primary determinant of pulmonary vascular resistance in a patient with hypoxic pulmonary vasoconstriction?
Answer: Alveolar hypoxia triggering smooth muscle contraction
Alveolar hypoxia triggers smooth muscle contraction in pulmonary arterioles, the hallmark mechanism of hypoxic pulmonary vasoconstriction.
A perfusionist notes the arterial waveform shows pulsus paradoxus. Which condition is most consistent with this finding?
Answer: Cardiac tamponade
Cardiac tamponade causes pulsus paradoxus due to pericardial pressure limiting right heart filling and exaggerating inspiratory BP drop.
Which factor has the greatest impact on myocardial oxygen consumption during cardiac surgery?
Answer: Heart rate and wall tension (preload/afterload)
Myocardial oxygen consumption is primarily determined by heart rate, wall stress (related to preload and afterload), and contractility.
In a patient with severe mitral regurgitation on bypass, which hemodynamic change would the perfusionist most likely observe before bypass?
Answer: Elevated left atrial pressure and pulmonary hypertension
Severe mitral regurgitation causes volume overload of the left atrium, elevating left atrial pressure and subsequently causing pulmonary hypertension.
What is the physiologic significance of the Bohr effect during cardiopulmonary bypass?
Answer: Decreased pH shifts the oxyhemoglobin curve right, facilitating O2 unloading to tissues
The Bohr effect describes how decreased pH (acidosis) shifts the oxyhemoglobin dissociation curve rightward, reducing hemoglobin's O2 affinity and facilitating tissue O2 delivery.