Free AACN Cardiac Surgery (CSC) exam (Adult) Practice Questions

Sample Practice Questions

Try these 10 sample questions from the AACN Cardiac Surgery (CSC) exam (Adult) practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1A nurse reviews the perfusion record of a patient returning from on-pump CABG. Which test documents the functional effect of the large heparin dose used before cardiopulmonary bypass?

   1. A.Prothrombin time with INR
   2. B.Activated clotting timeCorrect answer: B
   3. C.Platelet count
   4. D.Fibrinogen concentration

   Explanation: The STS guideline requires a "functional test of clot inhibition before initiation of CPB". Activated clotting time provides this functional assessment during high-dose heparinization. INR primarily assesses the vitamin K-dependent pathway, while platelet count and fibrinogen concentration measure components rather than the required whole-blood anticoagulant effect.

   Reference: STS/SCA/AmSECT Anticoagulation During Cardiopulmonary Bypass — pp. 652-653, Heparin Dosing, Class IIa recommendations

2. 2Two hours after CABG, a patient has a MAP of 52 mm Hg, cardiac index of 1.5 L/min/m², PAOP of 24 mm Hg, cool extremities and oliguria. Echocardiography shows severe left ventricular dysfunction without a pericardial collection. Which shock mechanism best explains these findings?

   1. A.Cardiogenic shockCorrect answer: A
   2. B.Hypovolemic shock
   3. C.Distributive shock
   4. D.Obstructive shock

   Explanation: NHLBI describes cardiogenic shock as occurring when the "heart cannot pump enough blood and oxygen" to vital organs. Low forward output with elevated left-sided filling pressure and demonstrated LV dysfunction identifies pump failure. The findings do not indicate inadequate filling, primary vasodilation or mechanical pericardial obstruction.

   Reference: NHLBI Cardiogenic Shock — What is cardiogenic shock?

3. 3A nurse reassesses a patient after a prescribed fluid-challenge aliquot following cardiac surgery. Which paired response most strongly argues against automatically giving another aliquot?

   1. A.PAOP increases by 2 mm Hg and stroke volume increases by 25%
   2. B.PAOP is unchanged and stroke volume increases by 20%
   3. C.PAOP increases by 1 mm Hg and stroke volume increases by 15%
   4. D.PAOP increases by 6 mm Hg and stroke volume remains unchangedCorrect answer: D

   Explanation: The chapter warns against "distention of the ventricle" from injudicious loading. A substantial rise in filling pressure without improved stroke volume shows no observed output benefit and raises concern that more volume will add pressure and distention. The other responses demonstrate increased stroke volume with little or no pressure rise. These are illustrative measured responses, not claims of official fluid-responsiveness cutoffs.

   Reference: Postoperative Care of the Cardiac Surgical Patient — Management of Low Cardiac Output, volume administration

4. 4A postoperative patient's measured cardiac output is 3.6 L/min and body surface area is 1.8 m². What cardiac index should the nurse record?

   1. A.1.8 L/min/m²
   2. B.2.0 L/min/m²Correct answer: B
   3. C.3.6 L/min/m²
   4. D.6.5 L/min/m²

   Explanation: Merck states that cardiac index corrects output for "body surface area" by division. CI = CO/BSA = 3.6 L/min ÷ 1.8 m² = 2.0 L/min/m². Using BSA itself gives 1.8, failing to divide gives 3.6, and multiplying gives 6.48, rounded to 6.5; each is the wrong operation.

   Reference: Merck Manual Professional: Monitoring and Testing the Critical Care Patient — Pulmonary Artery Catheterization, Cardiac output

5. 5An operative handoff identifies the procedure as off-pump coronary artery bypass grafting. Which description should the receiving cardiac surgery nurse expect in the operative record?

   1. A.The heart was arrested while a bypass circuit maintained circulation.
   2. B.The heart kept beating while a bypass circuit supported circulation.
   3. C.The circulation was arrested after deep systemic cooling.
   4. D.The heart kept beating while a stabilizing device steadied the operative area.Correct answer: D

   Explanation: NHLBI says off-pump CABG is performed "without stopping the heart and using a heart-lung bypass machine" and that "The heart is steadied with a mechanical device". The correct description is a beating heart stabilized without bypass. Arrested-heart bypass, beating-heart bypass and hypothermic circulatory arrest are different support strategies.

   Reference: NHLBI Coronary Artery Bypass Grafting: During Surgery — Off-pump CABG

6. 6During rewarming after cardiac surgery, a patient remains hypotensive despite adequate volume replacement. Cardiac index is 3.4 L/min/m², PAOP is 12 mm Hg and systemic vascular resistance is markedly reduced. Which change is primarily responsible for the low blood pressure?

   1. A.Increased pulmonary vascular resistance
   2. B.Reduced left ventricular contractility
   3. C.Reduced systemic vascular toneCorrect answer: C
   4. D.Increased intrapericardial pressure

   Explanation: Merck identifies "arterial or venous vasodilation" as a mechanism of distributive hypotension. Here, preserved cardiac output with low SVR points to loss of systemic vascular tone. Primary LV pump failure and pericardial compression would reduce forward output, while pulmonary resistance primarily burdens the right ventricle.

   Reference: Merck Manual Professional: Shock — Etiology and Classification, Distributive shock

7. 7The nurse reviews possible volume expanders for a patient after cardiopulmonary bypass. Which solution does the STS blood-management guideline specifically advise against as a CPB volume expander because of bleeding risk?

   1. A.Balanced crystalloid solution
   2. B.Hydroxyethyl starch solutionCorrect answer: B
   3. C.Human albumin solution
   4. D.Isotonic saline solution

   Explanation: The STS guideline links hydroxyethyl starch to a "risk of bleeding" and does not recommend it as a volume expander in CPB patients. The question concerns that specific recommendation; it does not imply that every alternative is equally appropriate for every patient or that one fluid replaces individualized assessment.

   Reference: STS/SCA/AmSECT/SABM Patient Blood Management Guideline — Table 1, volume expansion

8. 8A nurse obtains pulmonary artery occlusion pressure in a patient without significant mitral valve disease, major compliance abnormalities or high PEEP. Which pressure does this measurement normally approximate?

   1. A.Mean right atrial pressure
   2. B.Peak right ventricular systolic pressure
   3. C.Mean left atrial pressureCorrect answer: C
   4. D.Peak aortic systolic pressure

   Explanation: Merck explains that PAOP normally approximates "mean left atrial pressure". With the stated limitations excluded, it is used as a left-sided filling-pressure estimate. It is not a direct measurement of right atrial pressure or either ventricular or aortic peak systolic pressure.

   Reference: Merck Manual Professional: Monitoring and Testing the Critical Care Patient — Pulmonary artery occlusion pressure

9. 9A patient has just undergone mechanical mitral valve replacement. When reviewing the intended vitamin K antagonist regimen with the team, which target INR should the nurse anticipate for this prosthesis?

   1. A.1.5
   2. B.2.0
   3. C.3.0Correct answer: C
   4. D.2.5

   Explanation: The ACC/AHA guideline summary states, "For mechanical mitral valve replacement: INR of 3.0". The valve position and mechanical prosthesis determine this target; the other values are not the specified target for a mechanical mitral valve.

   Reference: ACC 2020 Heart Valve Disease Guideline: Key Perspectives, Part 3 — Prosthetic Valves, Antithrombotic therapy

10. 10A cardiac surgery patient has substantial recent blood loss, tachycardia, CVP 2 mm Hg, PAOP 4 mm Hg and a falling stroke volume. Echocardiography shows no pericardial collection and preserved systolic contraction. What most directly explains the fall in stroke volume?

    1. A.Reduced preload from loss of circulating volumeCorrect answer: A
    2. B.Increased afterload from pulmonary vascular obstruction
    3. C.Reduced contractility from left ventricular ischemia
    4. D.Impaired relaxation from constrictive pericardial disease

    Explanation: Merck defines hypovolemic shock by a "critical decrease in intravascular volume". Blood loss and low right- and left-sided filling pressures indicate inadequate preload. The preserved contraction and absence of a collection argue against the competing pump and pericardial mechanisms.

    Reference: Merck Manual Professional: Shock — Etiology and Classification, Hypovolemic shock