PCCN Cardiovascular System

Question 1

Which of the following hemodynamic parameters is most indicative of left ventricular preload?

Accepted Answer

Pulmonary artery wedge pressure (PAWP)

Answer

Pulmonary artery wedge pressure (PAWP), also known as pulmonary capillary wedge pressure (PCWP), is the most accurate hemodynamic parameter for estimating left ventricular preload. It reflects the pressure in the left atrium and, indirectly, the left ventricular end-diastolic pressure, which determines the stretch of the left ventricular muscle fibers before contraction. This measurement is crucial for assessing fluid status and cardiac function.

Question 2

A patient is admitted with acute decompensated heart failure. Which medication class is most appropriate to reduce preload and relieve pulmonary congestion?

Accepted Answer

Loop diuretics

Answer

Loop diuretics, such as furosemide, are highly effective in acute decompensated heart failure because they promote rapid diuresis. By inhibiting sodium and chloride reabsorption in the loop of Henle, they reduce circulating blood volume. This action directly decreases preload and alleviates pulmonary congestion, which are key goals in managing acute heart failure.

Question 3

Which ECG change is commonly associated with hypokalemia?

Accepted Answer

U waves

Answer

Hypokalemia, a low potassium level, commonly manifests on an ECG as the presence of U waves, which are small, positive deflections following the T wave. It can also cause flattened or inverted T waves and a prolonged QT interval. Peaked T waves, in contrast, are characteristic of hyperkalemia.

Question 4

What is the most appropriate intervention for a patient in atrial fibrillation with a rapid ventricular response and signs of hemodynamic instability?

Accepted Answer

Initiate synchronized cardioversion

Answer

For a patient in atrial fibrillation with a rapid ventricular response who is hemodynamically unstable (e.g., hypotension, altered mental status), immediate synchronized cardioversion is the most appropriate intervention. This electrical therapy rapidly converts the rhythm to restore hemodynamic stability. Medications are used for rate control in stable patients, not for unstable rhythms.

Question 5

A patient is post-op day 1 from coronary artery bypass graft (CABG) surgery and develops muffled heart sounds and hypotension. What complication should the nurse suspect?

Accepted Answer

Cardiac tamponade

Answer

Muffled heart sounds and hypotension in a post-CABG patient are classic signs of cardiac tamponade, a life-threatening complication where fluid accumulates in the pericardial sac. This fluid compresses the heart, impairing ventricular filling and leading to decreased cardiac output and hypotension. Other signs include jugular venous distension, forming Beck's triad.

PCCN Exam Practice Test

PCCN Exam Practice Test

PCCN Cardiovascular System