Hemodynamic Monitoring Flashcards

A patient's pulmonary capillary wedge pressure (PCWP) is 22 mmHg. This finding most likely indicates:

Answer: Left ventricular failure

An elevated PCWP above 18 mmHg reflects increased left atrial pressure, indicating left ventricular failure or fluid overload.

During thermodilution cardiac output measurement, which factor would cause a falsely HIGH cardiac output reading?

Answer: Injecting cold injectate too slowly

Injecting the cold injectate too slowly allows it to warm before reaching the thermistor, producing a smaller temperature change and falsely elevated CO calculation.

Which hemodynamic parameter is calculated using the formula: (MAP - RAP) / CO × 80?

Answer: Systemic vascular resistance (SVR)

SVR = (MAP − RAP) / CO × 80, expressed in dyne·sec·cm⁻⁵, quantifying afterload to the left ventricle.

A patient has a cardiac output of 4 L/min and a body surface area of 2.0 m². What is the cardiac index?

Answer: 2.0 L/min/m²

Cardiac index = CO / BSA = 4 / 2.0 = 2.0 L/min/m², which is at the lower limit of normal (normal: 2.2–4.0).

Which waveform component of the arterial pressure tracing represents the closure of the aortic valve?

Answer: Dicrotic notch

The dicrotic notch is a brief pressure rise followed by a dip on the descending limb, marking aortic valve closure at the end of systole.

When zeroing an arterial line transducer, the stopcock should be positioned at the level of the:

Answer: Phlebostatic axis (right atrium)

The phlebostatic axis (4th intercostal space, mid-axillary line) approximates the right atrium and is the standard reference for zeroing vascular pressure transducers.

A CVT observes a pulmonary artery waveform that has changed to a wedge (PCWP) waveform without balloon inflation. The most appropriate immediate action is to:

Answer: Notify the physician of catheter migration

Spontaneous wedging indicates the catheter has migrated distally and poses a risk of pulmonary infarction, requiring immediate physician notification.