CVP Cannulation Techniques and Circulatory Support Flashcards

During which phase of the cardiac cycle does the intra-aortic balloon pump (IABP) inflate?

Answer: Diastole

The IABP inflates during diastole to augment coronary perfusion pressure and deflates just before systole to reduce left ventricular afterload.

What hemodynamic effect does IABP deflation immediately before systole produce?

Answer: Reduced aortic end-diastolic pressure, decreasing afterload

Rapid IABP deflation creates a sudden volume displacement in the aorta just before systole, lowering aortic end-diastolic pressure and reducing myocardial oxygen demand.

Which signal does the perfusionist use to trigger IABP inflation timing?

Answer: ECG R-wave or arterial pressure waveform

IABP triggering uses either the ECG R-wave (in sinus rhythm) or the arterial pressure waveform to synchronize balloon inflation with diastole.

What is the primary hemodynamic mechanism of the Impella left ventricular assist device?

Answer: Drawing blood from the LV cavity and expelling it into the ascending aorta to unload the LV

The Impella is a catheter-based axial flow pump positioned across the aortic valve that actively pulls blood from the LV and propels it into the aorta, unloading the left ventricle.

How does ECMO for postcardiotomy cardiogenic shock differ fundamentally from standard intraoperative CPB?

Answer: ECMO provides prolonged mechanical circulatory support over days to weeks outside the operative setting

Unlike CPB used for hours in the sterile operative field, ECMO is configured for continuous mechanical support over days to weeks in the ICU to allow myocardial recovery.

Which condition is a contraindication to intra-aortic balloon pump placement?

Answer: Aortic regurgitation

Aortic regurgitation contraindicates IABP because diastolic balloon inflation increases aortic root pressure, worsening regurgitant backflow into the LV and increasing ventricular volume overload.