CCRN/PCCN Practice Questions

 Which of the following is TRUE regarding the S4 heart sound?

A. It can be heard in children

B. It can never be heard in A-fib

C. It is best heard with the diaphragm

D. It is a systolic extra sound  

Answer:  B  Remember that the S4 is known as the 'atrial gallop' sound.  It occurs as the atria contract duing the end of ventricular diastole due to ventricular non compliance.  We know it as 'atrial kick'.  Since the atria are fibrillating .... rather than contracting, you would never hear an S4 with atrial fib.  S4 is always pathologic so it is not a sound that should be heard in children (although S3 can be).  It is best heard with the bell of the stethoscope.  It is a diastolic extra sound.

A 66-year-old male presents with retrosternal chest pressure, diaphoresis, and shortness of breath.  Cardiac biomarkers are pending.  A 12-lead ECG is completed and shows ST segment depression and T-wave inversion.  It is crucial for the critical care nurse to suspect:

A. ST-elevation MI

B. Cardiac ischemia

C. Non ST-elevation MI

D. Coronary vasospasm

Answer:  C  This patient presents with ST segment depression and T-wave inversion.  This may indicate a Non ST Elevation MI.  Biomarkers will be valuable here in helping us to determine whether this is true or not.  This type of MI involves the inner surface of the heart . . . that is why it was once called a 'subendocardial MI'.  ST elevation (option A) indicates a 'transmural' infarct which involves all layers of the heart.  It is sometimes called a 'through and through' MI.  Coronary vasospasm (option D) would produce ST segment elevation.

A patient is admitted with an acute MI & cardiogenic shock. He is taken to the cath lab and found to have multivessel disease which requires bypass surgery. Which of the following conditions would prevent the insertion of an intra aortic balloon pump to support cardiac function?

A. Papillary muscle rupture

B. Incompetent aortic valve

C. Left ventricular failure

D. Refractory unstable angina

Answer:  B  Intra-aortic balloon insertion would be contraindicated in the face of aortic insufficiency because balloon inflation would worsen the aortic regurgitation.   In all of the remaining answers IABP insertion would take the workload off the left ventricle and decrease afterload, increase coronary artery perfusion, and decrease myocardial oxygen consumption. 

 A patient is admitted to the ICU with hypotension, tachycardia and fever.  The abdomen is distended and firm.  Bowel sounds are absent.  Which of the following labs would NOT support a diagnosis of bowel obstruction?

A. Increased white blood cell count

B. Decreased BUN

C. Decreased bicarbonate

D. Increased hematocrit

Answer:  B  The BUN would increase ... not decrease in a bowel obstruction due to dehydration.  Leukocytosis (an elevated WBC) would be present due to toxic proliferation of bacteria across the damaged membrane of the bowel.  The hematocrit would be increased due to dehydration and a hemoconcentration effect.  The bicarbonate would decrease due to a developing metabolic acidosis. 

A patient in the ICU with a diagnosis of cardiogenic shock post myocardial infarction develops new onset of a holosystolic murmus and a giant V-wave in the PAOP tracing.  Cardiac output/index drop and the heart rate increases to 160/minute.  The most likely  cause of this event is:

A.  Acute ventricular septal rupture

B.  Sustained ventricular tachycardia

C.  Acute mitral insufficiency

D.  Ruptured left ventricle

Answer: C Acute mitral insufficiency.  While acute ventricular septal rupture will cause a holosystolic murmur and a drop in cardiac output/index, it would not cause an elevated v-wave in the PAOP tracing. In the case of ventricular septal rupture, we would look for a 'step-up' in oxygenation between the right atrium and the pulmonary artery. Sustained ventricular tachycardia would not result in the new onset of a holosystolic murmur or a giant v-wave although it would cause a drop in cardiac output/index.  A ruptured left ventricle would not cause a holosystolic murnur or a giant v-wave although it would cause a drop in CO/CI.  The patient would develope signs/symptoms of cardiac tamponade.