Nokea
A group of nurses are participating in orientation to a telemetry unit. What should the staff educator tell this class about ST segments?
- A. They are the part of an ECG that reflects systole.
- B. They are the part of an ECG used to calculate ventricular rate and rhythm.
- C. They are the part of an ECG that reflects the time from ventricular depolarization through repolarization.
- D. They are the part of an ECG that represents early ventricular repolarization.
Correct Answer: D
Rationale: ST segment is the part of an ECG that reflects the end of the QRS complex to the beginning of the T wave. The part of an ECG that reflects repolarization of the ventricles is the T wave. The part of an ECG used to calculate ventricular rate and rhythm is the RR interval. The part of an ECG that reflects the time from ventricular depolarization through repolarization is the QT interval.
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A patient is scheduled for catheter ablation therapy. When describing this procedure to the patients family, the nurse should address what aspect of the treatment?
- A. Resetting of the hearts contractility
- B. Destruction of specific cardiac cells
- C. Correction of structural cardiac abnormalities
- D. Clearance of partially occluded coronary arteries
Correct Answer: B
Rationale: Catheter ablation destroys specific cells that are the cause or central conduction route of a tachydysrhythmia. It does not reset the hearts contractility and it does not address structural or vascular abnormalities.
A patient the nurse is caring for has a permanent pacemaker implanted with the identification code beginning with VVI. What does this indicate?
- A. Ventricular paced, ventricular sensed, inhibited
- B. Variable paced, ventricular sensed, inhibited
- C. Ventricular sensed, ventricular situated, implanted
- D. Variable sensed, variable paced, inhibited
Correct Answer: A
Rationale: The identification of VVI indicates ventricular paced, ventricular sensed, inhibited.
The nurse caring for a patient whose sudden onset of sinus bradycardia is not responding adequately to atropine. What might be the treatment of choice for this patient?
- A. Implanted pacemaker
- B. Trancutaneous pacemaker
- C. ICD
- D. Asynchronous defibrillator
Correct Answer: B
Rationale: If a patient suddenly develops a bradycardia, is symptomatic but has a pulse, and is unresponsive to atropine, emergency pacing may be started with transcutaneous pacing, which most defibrillators are now equipped to perform. An implanted pacemaker is not a time-appropriate option. An asynchronous defibrillator or ICD would not provide relief.
A patient converts from normal sinus rhythm at 80 bpm to atrial fibrillation with a ventricular response at 166 bpm. Blood pressure is 162/74 mm Hg. Respiratory rate is 20 breaths per minute with normal chest expansion and clear lungs bilaterally. IV heparin and Cardizem are given. The nurse caring for the patient understands that the main goal of treatment is what?
- A. Decrease SA node conduction
- B. Control ventricular heart rate
- C. Improve oxygenation
- D. Maintain anticoagulation
Correct Answer: B
Rationale: Treatment for atrial fibrillation is to terminate the rhythm or to control ventricular rate. This is a priority because it directly affects cardiac output. A rapid ventricular response reduces the time for ventricular filling, resulting in a smaller stroke volume. Control of rhythm is the initial treatment of choice, followed by anticoagulation with heparin and then Coumadin.
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.