chapter 26
patient with mitral valve stenosis and coronary artery disease (CAD) is in the telemetry unit with pneumonia. The nurse assesses a 6-second rhythm strip and determines that the ventricular rhythm is highly irregular at 88, with no discernible P waves. What does the nurse determine this rhythm to be? Atrial flutter Ventricular flutter Sinus tachycardia Nonparoxysmal junctional tachycardia
Atrial flutter Explanation: Atrial flutter occurs because of a conduction defect in the atrium and causes a rapid, regular atrial rate, usually between 250 and 400 bpm and results in P waves that are saw-toothed. Ventricular rhythm may be irregular, and P waves may be absent. Ventricular rate usually ranges between 75 and 150 bpm.
The nurse analyzes the electrocardiogram (ECG) strip of a stable patient admitted to the telemetry unit. The client's ECG strip demonstrates PR intervals that measure 0.24 seconds. What is the nurse's most appropriate action?
Document the findings and continue to monitor the patient Explanation: The client's electrocardiogram (ECG) tracing indicates a first-degree atrioventricular (AV) block. First-degree AV block rarely causes any hemodynamic effect; the other blocks may result in decreased heart rate, causing a decrease in perfusion to vital organs, such as the brain, heart, kidneys, lungs, and skin. The most appropriate action by the nurse is to document the findings and continue to monitor the client.
The nurse is aware that parasympathetic stimulation and certain medications can cause first-degree AV block. Choose the medication that should be evaluated. Inderal Coumadin Indocin Celebrex
Inderal Explanation: Beta-blockers, calcium channel blockers, or digoxin can interfere with conduction and should be evaluated.
A patient has a persistent third-degree heart block and has had several periods of syncope. What priority treatment should the nurse anticipate for this patient? Insertion of a pacemaker Administration of atropine Administration of epinephrine Insertion of an implantable cardioverter defibrillator (ICD)
Insertion of a pacemaker Explanation: Third-degree AV block, also known as a complete block, occurs when no atrial impulse is conducted through the AV node into the ventricles. A permanent pacemaker may be necessary if the block persists. Reference:
A nurse should obtain serum levels of which electrolytes in a client with frequent episodes of ventricular tachycardia? Calcium and magnesium Potassium and calcium Magnesium and potassium Potassium and sodium
Magnesium and potassium Explanation: Hypomagnesemia as well as hypokalemia and hyperkalemia are common causes of ventricular tachycardia. Calcium imbalances cause changes in the QT interval and ST segment. Alterations in sodium level don't cause rhythm disturbances.
A nurse is caring for a client who is on a continuous cardiac monitor. When evaluating the client's rhythm strip, the nurse notes that the QRS interval has increased from 0.08 second to 0.14 second. Based on this finding, the nurse should withhold continued administration of which drug? Metoprolol (Lopressor) Procainamide (Pronestyl) Propafenone (Rythmol) Verapamil (Calan)
Procainamide (Pronestyl) Explanation: Procainamide may cause an increased QRS complexes and QT intervals. If the QRS duration increases by more than 50%, then the nurse should withhold the drug and notify the physician of her finding. Metoprolol may cause increased PR interval and bradycardia. Propafenone and verapamil may cause bradycardia and atrioventricular blocks.
The nurse takes a preoperative ECG on a 48-year-old patient. She notices that there is a longer than normal distance between right ventricular depolarization and repolarization. She documents the strip finding and notifies the surgeon. Her conclusion was based on an abnormality in which of the following? ST segment TP interval QT interval QRS complex
QT interval Explanation: The QT interval represents the total time for right ventricular depolarization and repolarization. The ST segment only represents early ventricular repolarization. The QRS complex represents ventricular depolarization. The TP interval is measured from the end of the T wave to beginning of the P wave.
The nurse reviews the ECG strip, which indicates extended time between ventricular depolarization and repolarization. He checked the ventricular rate and rhythm again. To do that, the nurse would have to check which of the following? PP interval QT interval RR interval
RR interval Explanation: The RR interval is measured from the end of one QRS complex to the beginning of the next QRS complex and is the best recording to determine ventricular rate and rhythm.
The registered nurse reviewed the patient's q4h vital signs recorded by the LPN. He noticed a consistent pattern of heart rate recordings between 48 and 58 bpm over a 24-hour period of time. The nurse, aware that bradycardia can be a side-effect of medications, checked the patient's electronic health record. Select the medication that might cause bradycardia. Aminophylline Atropine Tenormin Epinephrine
Tenormin Explanation: Beta-blockers can lower the heart rate. The other choices stimulate the sympathetic response.
client has an irregular heart rate of around 100 beats/minute and a significant pulse deficit. What component of the client's history would produce such symptoms? atrial fibrillation atrial flutter heart block bundle branch block
atrial fibrillation Explanation: In atrial fibrillation, several areas in the right atrium initiate impulses resulting in disorganized, rapid activity. The atria quiver rather than contract, producing a pulse deficit due to irregular impulse conduction to the AV node. The ventricles respond to the atrial stimulus randomly, causing an irregular ventricular heart rate, which may be too infrequent to maintain adequate cardiac output. Atrial flutter, heart block, and bundle branch block would not produce these symptoms.
The nurse is caring for a client who has premature ventricular contractions. What sign or symptom is observed in this client? Fluttering Nausea Hypotension Fever
Correct response: Fluttering Explanation: Premature ventricular contractions usually cause a flip-flop sensation in the chest, sometimes described as "fluttering." Associated signs and symptoms include pallor, nervousness, sweating, and faintness. Symptoms of premature ventricular contractions are not nausea, hypotension, and fever. Reference:
When the appropriate electrocardiogram (ECG) complex follows the pacing spike, it is said to be triggered. captured. inhibited. nonsynchronous.
Correct response: captured. Explanation: Capture is a term used to denote that the appropriate electrocardiogram (ECG) complex followed by the pacing spike. Triggered response means that the pacemaker will respond when it senses intrinsic heart activity. Inhibited response means that the response of the pacemaker is controlled by the activity of the client's heart.
Which dysrhythmia has an atrial rate between 250 and 400, with saw-toothed P waves? Atrial flutter Atrial fibrillation Ventricular fibrillation Ventricular tachycardia
Atrial flutter Explanation: Atrial flutter occurs in the atrium and creates impulses at a regular atrial rate between 250 and 400 times per minute. The P waves are saw-toothed in shape. Atrial fibrillation causes a rapid, disorganized, and uncoordinated twitching of atrial musculature. Ventricular fibrillation is a rapid, disorganized ventricular rhythm that causes ineffective quivering of the ventricles. Ventricular tachycardia is defined as three or more PVCs in a row, occurring at a rate exceeding 100 beats per minute.
A client has had a pacemaker inserted and is ready for discharge. The nurse is providing education about pacemaker safety. Which of the following are items that the nurse will be sure to address? Choose all that apply. Do not spend time near a microwave oven. Monitor your pulse once a month. Carry a card identifying yourself as a pacemaker recipient. Avoid large magnetic fields. Sit at least 12 feet from television sets.
Carry a card identifying yourself as a pacemaker recipient. Avoid large magnetic fields. Explanation: Recent pacemaker technology allows clients to safely use most household electronic appliances and devices, including microwave ovens, electric tools, and televisions. The client with a pacemaker should monitor his or her pulse daily. He or she should always carry medical identification of pacemaker use. The client should avoid large magnetic fields (eg, large motors, magnetic resonance imaging, arc welding, electrical substations).
A pacemaker is the treatment of choice for what cardiac dysrhythmia? Supraventricular tachycardia Atrial flutter Ventricular fibrillation Complete heart block
Complete heart block Explanation: Pacemaker insertion is the treatment for complete heart block. Treatments for supraventricular tachycardia are: valsalva maneuver, unilateral carotid massage, immersion of face in ice water, administration of IV adenosine, cardioversion, and radiofrequency ablation. Cardioversion and drug therapy are used for the treatment of atrial flutter. Treatment for ventricular fibrillation is defibrillation preceded by or followed with epinephrine.
The nurse is assigned to care for several clients admitted to a telemetry unit. Which clients should the nurse assess first? A client whose implantable cardioverter defibrillator (ICD) fired twice on the prior shift, requiring amiodarone IV A client who received elective cardioversion 1 hour ago and whose heart rate (HR) is 115 bpm A client diagnosed with new onset of atrial fibrillation, requiring scheduled IV diltiazem A client returned from an electrophysiology procedure 2 hours ago, reporting constipation
Correct response: A client whose implantable cardioverter defibrillator (ICD) fired twice on the prior shift, requiring amiodarone IV Explanation: The client's implantable cardioverter defibrillator (ICD) that has fired on the previous shift should be seen first. This client is in need of antidysrhythmic medication, which is the priority intervention. The remaining clients should be seen after this client and are in no acute distress
A client has started to exhibit dangerous PVCs in the cardiac postoperative unit. The client has been given a bolus of lidocaine and is under continuous IV infusion, but serious side effects, including hypotension during administration, could occur. What should the nurse be ready to do? Adjust the IV infusion. Administer additional lidocaine. Prepare for defibrillation. Call for the doctor and just wait.
Correct response: Adjust the IV infusion. Explanation: Call for the physician while adjusting the IV infusion to the slowest possible rate until the physician can examine the patient.
Two clients in cardiac rehabilitation are discussing the differences between scheduled cardioversion and unexpected defibrillation. Which statement does the nurse note is not correct? Both procedures sedate the clients. Cardioversion uses more electrical energy than defibrillation. Both used to eliminate ventricular dysrhythmias. Machine determines when electrical energy is delivered.
Correct response: Cardioversion uses more electrical energy than defibrillation. Explanation: Cardioversion uses less electrical energy (50 to 100 joules) than defibrillation (200 to 360 joules). All of the other statements are correct.
Which of the following does the nurse recognize as the therapeutic goal of radiofrequency catheter ablation for a client with cardiac dysrhythmias? Reperfusion of ischemic heart tissue Dilation of arterial blood vessels Destruction of errant tissue Stimulation of the impulse center
Correct response: Destruction of errant tissue Explanation: The therapeutic goal of radiofrequency catheter ablation is to destroy errant tissue, in hopes of allowing impulse conduction to travel over appropriate pathways. The goal does not include dilation of blood vessels or reperfusion of heart tissue. There is no stimulation of the heart.
Elective cardioversion is similar to defibrillation except that the electrical stimulation waits to discharge until an R wave appears. What does this prevent? Disrupting the heart during the critical period of atrial repolarization. Disrupting the heart during the critical period of ventricular repolarization. Disrupting the heart during the critical period of ventricular depolarization. Disrupting the heart during the critical period of atrial depolarization.
Correct response: Disrupting the heart during the critical period of ventricular repolarization. Explanation: It is similar to defibrillation. One difference is that the machine that delivers the electrical stimulation waits to discharge until it senses the appearance of an R wave. By doing so, the machine prevents disrupting the heart during the critical period of ventricular repolarization. Therefore, options A, C, and D are incorrect.
The nurse is assessing a client with mitral regurgitation. The nurse expects to note which of the following findings in this client? Dyspnea, fatigue, and weakness Dizziness, syncope, and palpitations Orthopnea, angina, and pulmonary edema Dry cough, wheezing, and hemoptysis
Correct response: Dyspnea, fatigue, and weakness Explanation: Chronic mitral regurgitation is often asymptomatic, but acute mitral regurgitation can cause dyspnea, fatigue, and weakness. Dizziness, syncope, and palpitations are usually symptoms of mitral valve prolapse. Orthopnea, angina, and pulmonary edema are more likely with aortic stenosis. Dry cough, wheezing, and hemoptysis are more likely with mitral stenosis.
Which nursing intervention must a nurse perform when administering prescribed vasopressors to a client with a cardiac dysrhythmia? Keep the client flat for one hour after administration Administer every five minutes during cardiac resuscitation Document heart rate before and after administration Monitor vital signs and cardiac rhythm
Correct response: Monitor vital signs and cardiac rhythm Explanation: The nurse should monitor the client's vital signs and cardiac rhythm for effectiveness of the medication and for side effects and should always have emergency life support equipment available when caring for an acutely ill client. The side effects of vasopressor drugs are hypertension, dysrhythmias, pallor, and oliguria. It is not necessary to place a client flat during or after vasopressor administration. When administering cholinergic antagonists, documentation of the heart rate is necessary.
The nurse expects to see which of the following characteristics on an ECG strip for a patient who has third-degree AV block? Extended PR interval More P waves than QRS complexes Atrial rate of 60 bpm or below Shortened QRS duration.
Correct response: More P waves than QRS complexes Explanation: There is no PR interval because there isn't any relationship between the P and R wave. No atrial impulse is conducted through the AV node; atrial and ventricular contractions are independent. With third-degree AV block, two separate impulses stimulate the heart; there is no synchrony or relationship.
hich term is used to describe a tachycardia characterized by abrupt onset, abrupt cessation, and a QRS of normal duration? Sinus tachycardia Atrial flutter Paroxysmal atrial tachycardia Atrial fibrillation
Correct response: Paroxysmal atrial tachycardia Explanation: Paroxysmal atrial tachycardia (PAT) is often caused by a conduction problem in the AV node and is now called AV nodal reentry tachycardia. Sinus tachycardia occurs when the sinus node regularly creates an impulse at a faster-than-normal rate. Atrial flutter occurs in the atrium and creates an atrial rate between 250 to 400 times per minute. Atrial fibrillation causes a rapid, disorganized, and uncoordinated twitching of atrial musculature.
The nurse cares for a client who has developed junctional tachycardia with a heart rate (HR) of 80 bpm. Which action should the nurse complete? Request a digoxin level be ordered Withhold the client's oral potassium supplement Prepare for emergent electrical cardioversion Prepare to administer IV lidocaine
Correct response: Request a digoxin level be ordered Explanation: The nurse should request a digoxin level be obtained. Junctional tachycardia generally does not have any detrimental hemodynamic effect; it may indicate a serious underlying condition, such as digitalis toxicity, myocardial ischemia, hypokalemia, or chronic obstructive pulmonary disease (COPD). Potassium supplements do not cause junctional tachycardia. Lidocaine is indicated for the treatment of premature ventricular contractions (PVCs). Because junctional tachycardia is caused by increased automaticity, cardioversion is not an effective treatment; in fact, it causes an increase in ventricular rate.
Which dysrhythmia is common in older clients? Sinus bradycardia Sinus tachycardia Atrial fibrillation Ventricular tachycardia
Correct response: Sinus bradycardia Explanation: Sinus bradycardia is a common dysrhythmia in older clients. Sinus tachycardia, atrial fibrillation, and ventricular tachycardia are not common dysrhythmias in older clients.
The nurse is preparing to administer adenosine (Adenocard) for a patient diagnosed with atrial flutter. Which of the following should be completed when giving this medication? The dose is administered rapid IV push. The dose is administered slow IV push. The medication is followed by a slow saline flush. The medication is followed by a rapid lactated Ringer's (LR) flush
Correct response: The dose is administered rapid IV push. Explanation: The dose is administered by rapid IV push (1 to 2 seconds), followed with a rapid saline flush. LR is not used during administration of this medication.
Undersensing occurs as a pacemaker malfunctions when which of the following occurs? The pacing spike occurs at the preset level despite the patient's intrinsic rhythm. The complex does not follow the pacing spike. There is total absence of the pacing spike. There is loss of pacing artifact.
Correct response: The pacing spike occurs at the preset level despite the patient's intrinsic rhythm. Explanation: Undersensing means that the pacing spike occurs at a preset interval despite the patient's intrinsic rhythm. Loss of capture occurs when a complex does not follow a pacing spike. Loss of pacing is total absence of the pacing spike. Oversensing occurs when there is a loss of pacing artifact.
Which electrocardiogram (ECG) characteristic is usually seen when a client's serum potassium level is low? U wave T wave P wave
Correct response: U wave Explanation: The U wave is an ECG waveform characteristic that may reflect Purkinje fiber repolarization. It is usually seen when a client's serum potassium level is low. The T wave is an ECG characteristic reflecting repolarization of the ventricles. It may become tall or "peaked" if a client's serum potassium level is high. The P wave is an ECG characteristic reflecting conduction of an electrical impulse through the atria. The QT interval is an ECG characteristic reflecting the time from ventricular depolarization to repolarization.
The nurse is working on a monitored unit assessing the cardiac monitor rhythms. Which waveform pattern needs attention first? Sustained asystole Supraventricular tachycardia Atrial fibrillation Ventricular fibrillation
Correct response: Ventricular fibrillation Explanation: Ventricular fibrillation is called the rhythm of a dying heart. It is the rhythm that needs attention first because there is no cardiac output, and it is an indication for CPR and immediate defibrillation. Sustained asystole either is from death, or the client is off of the cardiac monitor. Supraventricular tachycardia and atrial fibrillation is monitored and reported to the physician but is not addressed first.
caring for a client with vasovagal syncope, the nurse should know that the associated temporary loss of consciousness is most commonly related to: vestibular dysfunction. sudden vascular fluid shifting. postural hypotension. bradyrhythmia.
Correct response: bradyrhythmia. Explanation: Parasympathetic hyperactivity leading to sudden hypotension secondary to bradyrhythmia causes vasovagal syncope. That is, bradyrhythmia leads to cerebral ischemia which, in turn, leads to syncope. Vasovagal syncope isn't caused by vestibular (inner ear) dysfunction, postural hypotension, or vascular fluid shifting.
A client with a history of mitral stenosis is admitted to the intensive care unit (ICU) with the abrupt onset of atrial fibrillation. The client's heart rate ranges from 120 to 140 bpm. The nurse recognizes that interventions are implemented to prevent the development of embolic stroke. myocardial infarction. heart failure. renal failure.
Correct response: embolic stroke. Explanation: Intervention is implemented to prevent the development of an embolic event/stroke. Clients with a history of previous stroke, transient ischemic attack (TIA), embolic event, mitral stenosis, or prosthetic heart valve and who develop atrial fibrillation are at significant risk of developing an embolic stroke. Antithrombotic therapy is indicated for all clients with atrial fibrillation, especially those at risk of an embolic event, such as a stroke, and it is the only therapy that decreases cardiovascular mortality. These client are often placed on warfarin, in contrast to clients who have no risk factors, and who are often prescribed 81 to 325 mg of aspirin daily.
Each chamber of the heart has a particular role in maintaining cellular oxygenation. Which chamber is responsible for pumping blood to all the cells and tissues of the body? left ventricle left atrium right ventricle right atrium
Correct response: left ventricle Explanation: The left ventricle pumps blood to all the cells and tissues of the body. The left atrium receives oxygenated blood from the lungs. The right ventricle pumps blood to the lungs to be oxygenated. The right atrium receives deoxygenated blood from the venous system.
A client receives a pacemaker to treat a recurring arrhythmia. When monitoring the cardiac rhythm strip, the nurse observes extra pacemaker spikes that don't precede a beat. Which condition should the nurse suspect? Failure to pace Failure to capture Failure to sense Asystole
Failure to capture Explanation: Extra pacemaker spikes that don't precede a beat may indicate failure to capture, in which the pacemaker fires but the heart doesn't conduct the beat. In failure to pace, the pacemaker doesn't fire when it should; this causes hypotension and other signs of low cardiac output accompanied by bradycardia or a heart rate slower than the pacemaker's preset rate. In failure to sense, the pacemaker can't sense the client's intrinsic heartbeat; on the rhythm strip, spikes may fall on T waves, or they may fall regularly but at points at which they shouldn't appear. An absent heart rate or rhythm, reflected as a flat line on the rhythm strip, characterizes asystole.
Before a transesophageal echocardiogram, a nurse gives a client an oral topical anesthetic spray. When the client returns from the procedure, the nurse observes that he has no active gag reflex. In response, the nurse should: insert an oral airway. withhold food and fluids. position the client on his side. introduce a nasogastric (NG) tube.
withhold food and fluids. Explanation: Following a transesophageal echocardiogram in which the client's throat has been anesthetized, the nurse should withhold food and fluid until the client's gag reflex returns. There's no indication that oral airway placement would be appropriate. The client should be in the upright position, and the nurse needn't insert an NG tube.
