Dysrhythmias NCLEX Questions

15. What criteria should the nurse use to determine normal sinus rhythm for a client on a cardiac monitor? Check all that apply. 1. The RR intervals are relatively consistent 2. One P wave precedes each QRS complex 3. Four to eight complexes occur in a 6 second strip 4. The ST segment is higher than the PR interval 5. The QRS complex ranges from 0.12 to 0.20 second.

1, 2. The consistency of the RR interval indicates regular rhythm. A normal P wave before each complex indicates the impulse originated in the SA node. The number of complexes in a 6 second strip is multiplied by 10 to approximate the heart rate; normal sinus rhythm is 60 to 100. Elevation of the ST segment is a sign of cardiac ischemia and is unrelated to the rhythm. The QRS duration should be less than 0.12 second; the PR interval should be 0.12 to 0.20 second.

9. A client with rapid rate atrial fibrillation asks a nurse why the physician is going to perform carotid massage. The nurse responds that this procedure may stimulate the: 1. Vagus nerve to slow the heart rate 2. Vagus nerve to increase the heart rate; overdriving the rhythm. 3. Diaphragmic nerve to slow the heart rate 4. Diaphragmic nerve to overdrive the rhythm

1. Carotid sinus massage is one of the maneuvers used for vagal stimulation to decrease a rapid heart rate and possibly terminate a tachydysrhythmia. The others include inducing the gag reflex and asking the client to strain or bear down. Medication therapy often is needed as an adjunct to keep the rate down or maintain the normal rhythm.

6. A client is having frequent premature ventricular contractions. A nurse would place priority on assessment of which of the following items? 1. Blood pressure and peripheral perfusion 2. Sensation of palpitations 3. Causative factors such as caffeine 4. Precipitating factors such as infection

1. Premature ventricular contractions can cause hemodynamic compromise. The shortened ventricular filling time with the ectopic beats leads to decreased stroke volume and, if frequent enough, to decreased cardiac output. The client may be asymptomatic or may feel palpations. PVCs can be caused by cardiac disorders or by any number of physiological stressors, such as infection, illness, surgery, or trauma, and by the intake of caffeine, alcohol, or nicotine.

7. A client has developed atrial fibrillation, which a ventricular rate of 150 beats per minute. A nurse assesses the client for: 1. Hypotension and dizziness 2. Nausea and vomiting 3. Hypertension and headache 4. Flat neck veins

1. The client with uncontrolled atrial fibrillation with a ventricular rate more than 150 beats a minute is at risk for low cardiac output because of loss of atrial kick. The nurse assesses the client for palpitations, chest pain or discomfort, hypotension, pulse deficit, fatigue, weakness, dizziness, syncope, shortness of breath, and distended neck veins.

1. A nurse is assessing an electrocardiogram rhythm strip. The P waves and QRS complexes are regular. The PR interval is 0.16 second, and QRS complexes measure 0.06 second. The overall heart rate is 64 beats per minute. The nurse assesses the cardiac rhythm as: A. Normal sinus rhythm B. Sinus bradycardia C. Sick sinus syndrome D. First-degree heart block.

1. measurements are normal, measuring 0.12 to 0.20 second and 0.4 to 0.10 second, respectively.

8. A nurse is watching the cardiac monitor, and a client's rhythm suddenly changes. There are no P waves; instead there are wavy lines. The QRS complexes measure 0.08 second, but they are irregular, with a rate of 120 beats a minute. The nurse interprets this rhythm as: 1. Sinus tachycardia 2. Atrial fibrillation 3. Ventricular tachycardia 4. Ventricular fibrillation

2. Atrial fibrillation is characterized by a loss of P waves; an undulating, wavy baseline; QRS duration that is often within normal limits; and an irregular ventricular rate, which can range from 60 to 100 beats per minute (when controlled with medications) to 100 to 160 beats per minute (when uncontrolled).

5. A nurse is caring for a client with unstable ventricular tachycardia. The nurse instructs the client to do which of the following, if prescribed, during an episode of ventricular tachycardia? 1. Breathe deeply, regularly, and easily. 2. Inhale deeply and cough forcefully every 1 to 3 seconds. 3. Lie down flat in bed 4. Remove any metal jewelry

2. Cough cardiopulmonary resuscitation (CPR) sometimes is used in the client with unstable ventricular tachycardia. The nurse tells the client to use cough CPR, if prescribed, by inhaling deeply and coughing forcefully every 1 to 3 seconds. Cough CPR may terminate the dysrhythmia or sustain the cerebral and coronary circulation for a short time until other measures can be implemented.

2 A nurse notices frequent artifact on the ECG monitor for a client whose leads are connected by cable to a console at the bedside. The nurse examines the client to determine the cause. Which of the following items is unlikely to be responsible for the artifact? 1. Frequent movement of the client 2. Tightly secured cable connections 3. Leads applied over hairy areas 4. Leads applied to the limbs

2. Motion artifact, or "noise," can be caused by frequent client movement, electrode placement on limbs, and insufficient adhesion to the skin, such as placing electrodes over hairy areas of the skin. Electrode placement over bony prominences also should be avoided. Signal interference can also occur with electrode removal and cable disconnection.

11. While caring for a client who has sustained an MI, the nurse notes eight PVCs in one minute on the cardiac monitor. The client is receiving an IV infusion of D5W and oxygen at 2 L/minute. The nurse's first course of action should be to: 1. Increase the IV infusion rate 2. Notify the physician promptly 3. Increase the oxygen concentration 4. Administer a prescribed analgesic

2. PVCs are often a precursor of life-threatening dysrhythmias, including ventricular tachycardia and ventricular fibrillation. An occasional PVC is not considered dangerous, but if PVCs occur at a rate greater than 5 or 6 per minute in the post MI client, the physician should be notified immediately. More than 6 PVCs per minute is considered serious and usually calls for decreasing ventricular irritability by administering medications such as lidocaine. Increasing the IV infusion rate would not decrease the number of PVCs. Increasing the oxygen concentration should not be the nurse's first course of action; rather, the nurse should notify the physician promptly. Administering a prescribed analgesic would not decrease ventricular irritability.

14. When ventricular fibrillation occurs in a CCU, the first person reaching the client should: 1. Administer oxygen 2. Defibrillate the client 3. Initiate CPR 4. Administer sodium bicarbonate intravenously

2. Ventricular fibrillation is a death-producing dysrhythmia and, once identified, must be terminated immediately by precordial shock (defibrillation). This is usually a standing physician's order in a CCU.

10. A nurse notes that a client with sinus rhythm has a premature ventricular contraction that falls on the T wave of the preceding beat. The client's rhythm suddenly changes to one with no P waves or definable QRS complexes. Instead there are coarse wavy lines of varying amplitude. The nurse assesses this rhythm to be: 1. Ventricular tachycardia 2. Ventricular fibrillation 3. Atrial fibrillation 4. Asystole

2. Ventricular fibrillation is characterized by irregular, chaotic undulations of varying amplitudes. Ventricular fibrillation has no measurable rate and no visible P waves or QRS complexes and results from electrical chaos in the ventricles.

3. A nurse is watching the cardiac monitor and notices that the rhythm suddenly changes. There are no P waves, the QRS complexes are wide, and the ventricular rate is regular but over 100. The nurse determines that the client is experiencing: 1. Premature ventricular contractions 2. Ventricular tachycardia 3. Ventricular fibrillation 4. Sinus tachycardia

2. Ventricular tachycardia is characterized by the absence of P waves, wide QRS complexes (usually greater than 0.14 second), and a rate between 100 and 250 impulses per minute. The rhythm is usually regular.

4. A nurse is viewing the cardiac monitor in a client's room and notes that the client has just gone into ventricular tachycardia. The client is awake and alert and has good skin color. The nurse would prepare to do which of the following? 1. Immediately defibrillate 2. Prepare for pacemaker insertion 3. Administer amiodarone (Cordarone) intravenously 4. Administer epinephrine (Adrenaline) intravenously

3. First-line treatment of ventricular tachycardia in a client who is hemodynamically stable is the use of anti-dysrhythmics such as amiodarone (Cordarone), lidocaine (Xylocaine), and procainamide (Pronestyl). Cardioversion also may be needed to correct the rhythm (cardioversion is recommended for stable ventricular tachycardia). Defibrillation is used with pulseless ventricular tachycardia. Epinephrine would stimulate and already excitable ventricle and is contraindicated.

16. When auscultating the apical pulse of a client who has atrial fibrillation, the nurse would expect to hear a rhythm that is characterized by: 1. The presence of occasional coupled beats 2. Long pauses in an otherwise regular rhythm 3. A continuous and totally unpredictable irregularity 4. Slow but strong and regular beats

3. In atrial fibrillation, multiple ectopic foci stimulate the atria to contract. The AV node is unable to transmit all of these impulses to the ventricles, resulting in a pattern of highly irregular ventricular contractions.

13. A client with a bundle branch block is on a cardiac monitor. The nurse should expect to observe: 1. Sagging ST segments 2. Absence of P wave configurations 3. Inverted T waves following each QRS complex 4. Widening of QRS complexes to 0.12 second or greater.

4. Bundle branch block interferes with the conduction of impulses from the AV node to the ventricle supplied by the affected bundle. Conduction through the ventricles is delayed, as evidenced by a widened QRS complex.

12. The adaptations of a client with complete heart block would most likely include: 1. Nausea and vertigo 2. Flushing and slurred speech 3. Cephalalgia and blurred vision 4. Syncope and low ventricular rate

4. In complete atrioventricular block, the ventricles take over the pacemaker function in the heart but at a much slower rate than that of the SA node. As a result there is decreased cerebral circulation, causing syncope.