Nokea
The nursing educator is presenting a case study of an adult patient who has abnormal ventricular depolarization. This pathologic change would be most evident in what component of the ECG?
- A. P wave
- B. T wave
- C. QRS complex
- D. U wave
Correct Answer: C
Rationale: The QRS complex represents the depolarization of the ventricles and, as such, the electrical activity of that ventricle.
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A patient who is a candidate for an implantable cardioverter defibrillator (ICD) asks the nurse about the purpose of this device. What would be the nurses best response?
- A. To detect and treat dysrhythmias such as ventricular fibrillation and ventricular tachycardia
- B. To detect and treat bradycardia, which is an excessively slow heart rate
- C. To detect and treat atrial fibrillation, in which your heart beats too quickly and inefficiently
- D. To shock your heart if you have a heart attack at home
Correct Answer: A
Rationale: The ICD is a device that detects and terminates life-threatening episodes of ventricular tachycardia and ventricular fibrillation. It does not treat atrial fibrillation, MI, or bradycardia.
New nurses on the telemetry unit have been paired with preceptors. One new nurse asks her preceptor to explain depolarization. What would be the best answer by the preceptor?
- A. Depolarization is the mechanical contraction of the heart muscles.
- B. Depolarization is the electrical stimulation of the heart muscles.
- C. Depolarization is the electrical relaxation of the heart muscles.
- D. Depolarization is the mechanical relaxation of the heart muscles.
Correct Answer: B
Rationale: The electrical stimulation of the heart is called depolarization, and the mechanical contraction is called systole. Electrical relaxation is called repolarization, and mechanical relaxation is called diastole.
A cardiac care nurse is aware of factors that result in positive chronotropy. These factors would affect a patients cardiac function in what way?
- A. Exacerbating an existing dysrhythmia
- B. Initiating a new dysrhythmia
- C. Resolving ventricular tachycardia
- D. Increasing the heart rate
Correct Answer: D
Rationale: Stimulation of the sympathetic system increases heart rate. This phenomenon is known as positive chronotropy. It does not influence dysrhythmias.
The nurse is caring for a patient who has had a dysrhythmic event. The nurse is aware of the need to assess for signs of diminished cardiac output (CO). What change in status may signal to the nurse a decrease in cardiac output?
- A. Increased blood pressure
- B. Bounding peripheral pulses
- C. Changes in level of consciousness
- D. Skin flushing
Correct Answer: C
Rationale: The nurse conducts a physical assessment to confirm the data obtained from the history and to observe for signs of diminished cardiac output (CO) during the dysrhythmic event, especially changes in level of consciousness. Blood pressure tends to decrease with lowered CO and bounding peripheral pulses are inconsistent with this problem. Pallor, not skin flushing, is expected.
The nurse is caring for a patient who has had an ECG. The nurse notes that leads I, II, and III differ from one another on the cardiac rhythm strip. How should the nurse best respond?
- A. Recognize that the view of the electrical current changes in relation to the lead placement.
- B. Recognize that the electrophysiological conduction of the heart differs with lead placement.
- C. Inform the technician that the ECG equipment has malfunctioned.
- D. Inform the physician that the patient is experiencing a new onset of dysrhythmia.
Correct Answer: A
Rationale: Each lead offers a different reference point to view the electrical activity of the heart. The lead displays the configuration of electrical activity of the heart. Differences between leads are not necessarily attributable to equipment malfunction or dysrhythmias.