Chapter 36
What accurately describes the PR interval?
0.12 to 0.20 seconds. Time of depolarization and repolarization of ventricles.
The ECG pattern of a patient with a regular HR reveals 20 small squares between each R-R interval. What is the patient's heart rate?
1500/20=75 bmp
A patient with a regular heart rate has four QRS complexes between every 3 second marker on the ECG paper. Calculate the patient's heart rate.
4+4=8x10=80 bpm
Which rhythm pattern finding is indicative of PVCs?
A QRS complex >or= 0.12 seconds followed by a P wave.
The patient's PR interval comprises six small boxes on the ECG graph. What does the nurse determine that this indicates?
A problem with conduction from the SA node to the ventricular cells.
What action is included in the nurse's responsibilities in preparing to administer defibrillation?
Applying gel pads to the patient's chest.
What describes the SA node's ability to discharge an electrical impulse spontaneously?
Automaticity
A patient with a sinus node dysfunction has a permanent pacemaker inserted. Before discharge, what should the nurse include when teaching the patient?
Avoid standing near antitheft devices in doorways.
A patient on the cardiac telemetry unit goes into ventricular fibrillation and is unresponsive. Following initiation of the emergency call system, what is the next priority for the nurse in caring for this patient?
Begin CPR.
While providing discharge instructions to the patient who has had an implantable cardioverter defibrillator inserted, the nurse teaches the patient that if the ICD fires, he or she should do what?
Call the cardiologist.
In the patient with a dysrhythmia, which assessment indicates decreased cardiac output?
Chest pain and decreased mentation.
A patient's rhythm strip indicates a normal HR and rhythm with normal P waves and QRS complexes, but the PR interval is 0.26 second. What is the most appropriate action by the nurse?
Continue to assess the patient.
In the patient experiencing ventricular fibrillation, what is the rationale for using cardiac defibrillation?
Depolarize the cells of the myocardium to allow the SA node to resume pacemaker function.
The nurse plans close monitoring for the patient during eletrophysiologic testing because this test
Induces dysrhythmias that may require cardioversion or defibrillation to correct
What accurately describes electrocardiographic (ECG) monitoring?
Lead placement for V1 includes one lead each for right arm, right leg, left arm, and left leg with the fifth lead on the fourth intercostal space to the right of the sternal border.
A 54 year old patient who has no structural heart disease has an episode of syncope. An upright tilt table test is performed to rule out neurocardiogenic syncope. The nurse explains to the patient that if neurocardiogenic syncope is the problem, the patient will experience what?
Marked bradycardia and hypotension.
Which rhythm abnormality has an increased risk of ventricular tachycardia and ventricular fibrillation?
PVC on the T wave
What describes refractoriness?
Period in which heart tissue cannot be stimulated.
The nurse is evaluating the telemetry ECG rhythm strip. How should the nurse document the distorted P wave causing an irregular rhythm?
Premature atrial contraction (PAC).
A patient with an acute MI is having multifocal PVCs and ventricular couplets. He is alert and has a BP of 118/78 mm HG with an irregular pulse of 86 bpm. What is the priority nursing action at this time?
Prepare to administer antidysrhythmic drugs per protocol.
A patient with chest pain that is unrelieved by nitroglycerin is admitted to the coronary care unit for observation and diagnosis. While the patient has continuous ECG monitoring, what finding would most concern the nurse?
ST segment elevation.
The patient is brought to the emergency department with acute coronary syndrome. What changes should the nurse expect to see on the ECG if only myocardial injury has occurred?
ST segment elevation.
The use of catheter ablation therapy to "burn" areas of the cardiac conduction system is indicated for the treatment of
Tachydysrhythmias.
A patient with no history of heart disease has a rhythm strip that shows an occasional distorted P wave followed by normal AV and ventricular conduction. What should the nurse question the patient about?
The use of caffeine.
After defibrillation, the advanced cardiac life support nurse says that the patient has pulseless electrical activity. What is most important for the nurse to understand about this rhythm?
There is electrical activity with no mechanical response.
A patient with an acute myocardial infarction (MI) develops the following ECG pattern: atrial rate of 82 and regular, ventricular rate of 46 and regular, P wave and QRS complex are normal but there is no relationship between the P wave and the QRS complex. What dysrhythmia does the nurse identify this as and what treatment is expected?
Third degree heart block treated with a pacemaker.
What should the nurse reading the monitor strip call a rhythm with a regular PR interval but a blocked QRS complex?
Type II second degree AV block.
A patient with an acute MI has sinus tachycardia of 126 bpm. The nurse recognizes that if this dysrhythmia is not treated, the patient is likely to experience
an increase in infarct size.
