Chapter 52: Management of ST-Elevation Myocardial Infarction

Chapter 52: Management of ST-Elevation Myocardial Infarction

 

Complete Chapter Questions With Answers

 

Sample Questions Are Posted Below

 

1. A patient is being evaluated in the emergency department for complaints of severe chest pain. The ECG confirms an ST-elevation myocardial infarction (STEMI). Which drug would the nurse anticipate administering for the relief of chest pain?

a.	Meperidine (Demerol)
b.	Morphine
c.	Aspirin
d.	Hydromorphone (Dilaudid)

 

 

ANS:   B

Morphine is the treatment of choice for STEMI-associated pain. Morphine can also improve hemodynamics through its combined effects on preload and afterload. As a result, cardiac oxygen demand is reduced, which helps preserve ischemic myocardium.

Meperidine and hydromorphone are not indicated for relief of cardiac chest pain.

Although aspirin substantially reduces mortality, it is not indicated for pain relief but rather for its ability to suppress platelet aggregation.

 

DIF:    Cognitive Level: Application             REF:    p. 621

TOP:    Nursing Process: Planning

MSC:   NCLEX Client Needs Category: Physiological Integrity: Pharmacological and Parenteral Therapies

 

2. The nurse understands that the most effective way to preserve myocardial function and limit the size of an infarct is to implement/administer

a.	reperfusion therapy.
b.	morphine.
c.	nitroglycerin.
d.	aspirin.

 

 

ANS:   A

Reperfusion therapy, which includes fibrinolytic therapy or primary percutaneous coronary intervention (PCI), is the most effective way to preserve myocardial function and limit infarct size.

Morphine is indicated for the treatment of cardiac pain. In addition, through combined reduction of preload and afterload, morphine reduces oxygen demand, which helps preserve ischemic myocardium. However, morphine alone is not the most effective way to limit the size of a myocardial infarction.

Nitroglycerin reduces preload, thereby reducing oxygen demand. It also increases collateral blood flow to ischemic regions of the heart, which helps limit infarct size. However, nitroglycerin alone is not the most effective way to limit the size of a myocardial infarction and has not been shown to reduce mortality.

Aspirin is indicated to suppress platelet aggregation. Research has demonstrated a reduction in mortality when aspirin is administered to patients with an evolving STEMI. However, aspirin alone is not the most effective way to limit the size of a myocardial infarction.

 

DIF:    Cognitive Level: Application             REF:    p. 621

TOP:    Nursing Process: Planning

MSC:   NCLEX Client Needs Category: Physiological Integrity: Reduction of Risk Potential

 

3. The nurse is evaluating a patient admitted to the emergency department with an evolving STEMI for possible administration of thrombolytic therapy. Which of the following identified during history taking would contraindicate this type of therapy?

a.	The patient just completed her last menstrual cycle.
b.	The patient states that the chest pain started 1 hour ago.
c.	The patient has a history of a small cerebral aneurysm.
d.	The patient has hypertension that is well controlled by diuretic therapy.

 

 

ANS:   C

The absolute contraindications to thrombolytic therapy include known structural cerebrovascular lesions. This patient has a known cerebral aneurysm.

Active internal bleeding is an absolute contraindication for thrombolysis except for menses, and the patient has indicated she has completed her last cycle. There is no contraindication to administration.

Current guidelines indicate that thrombolytic therapy should be administered for chest pain that has been present for no longer than 12 hours. The patient meets this criterion for administration.

Although severe, poorly controlled hypertension is a relative contraindication, the patient’s hypertension is well controlled by medication therapy. Thrombolytics can be administered with caution.

 

DIF:    Cognitive Level: Analysis                  REF:    p. 622

TOP:    Nursing Process: Evaluation

MSC:   NCLEX Client Needs Category: Physiological Integrity: Pharmacological and Parenteral Therapies

 

4. The nurse is caring for a patient in the emergency department who complain of chest pain. While watching the telemetry monitor, the nurse notes new S-T elevation in lead II. Which labs should the nurse anticipate being ordered for this patient?

a.	Cardiac troponin T
b.	Potassium level
c.	Creatine kinase (CK)
d.	B-type natriuretic peptide (BNP)

 

 

ANS:   A

Cardiac-derived troponins (T and I) are considered the best serum markers for suspected STEMI. Cardiac troponins are detectable within 2 to 4 hours after symptom onset if infarction has occurred.

Measurement of the potassium level is not indicated. However, it should be evaluated in ST depression, which can be the result of hypokalemia or hyperkalemia.

A CK level is not specific enough. Unless specific isoenzymes are evaluated, it is not clear whether elevations are the result of other problems, such as musculoskeletal, cerebral, or renal injury.

BNP is used to diagnose heart failure.

 

DIF:    Cognitive Level: Application             REF:    p. 620

TOP:    Nursing Process: Planning

MSC:   NCLEX Client Needs Category: Physiological Integrity: Reduction of Risk Potential