Ch. 17 - Arrhythmias
The nurse is caring for a client who has premature ventricular contractions. After assessing the client, the nurse will likely need to document which observed sign or symptom?
palpitations Premature ventricular contractions usually cause a flip-flop sensation in the chest, sometimes described as "fluttering," "skipped beat," or "palpitations." Associated signs and symptoms include pallor, nervousness, sweating, and faintness. Symptoms of premature ventricular contractions are not nausea, hypotension, and fever
During electrical cardioversion, the defibrillator is set to synchronize with the electrocardiogram (ECG) so that the electrical impulse discharges during
ventricular depolarization. In cardioversion, the defibrillator is set to synchronize with the electrocardiogram (ECG) on the cardiac monitor so that the electrical impulse discharges during ventricular depolarization.
The nurse is providing teaching to a client with an implanted cardiac device. Which client statement indicates that teaching has been effective?
"I will not place my cell phone in my chest pocket." The implantable cardioverter defibrillator (ICD) is an electronic device that detects and terminates life-threatening episodes of tachycardia or fibrillation, especially those that are ventricular in origin. An ICD has a generator about the size of a pack of chewing gum that is implanted in a subcutaneous pocket, usually in the upper chest wall. Because of this, electronic devices should not be placed near the implanted generator as this could cause electromagnetic interference. There is no reason for the client to stop using the microwave oven. Since the MRI is a large magnetic field, MRIs should not be done in the future. A client is not restriced from flying due to having a pacemaker..
An older adult patient with a recent history of syncope has undergone an initial diagnostic workup that has failed to identify the cause of his fainting. As a result, continuous electrocardiographic (ECG) monitoring (Holter monitoring) has been ordered. When initiating this diagnostic testing, what patient education should the nurse provide?
"Record your activities in your log so that they can be cross-referenced with your ECG readings." During ambulatory ECG, the patient keeps a diary noting the type and time of symptoms or performance of unusual activities. It is unnecessary to avoid activity or electrical devices. It is unsafe and unnecessary to discontinue medications during Holter monitoring
A client is unconscious on arrival to the emergency department. The nurse in the emergency department identifies that the client has a permanent pacemaker due to which characteristic?
"Spike" on the rhythm strip Confirmation that the client has a permanent pacemaker is the characteristic "spike" identified by a thin, straight stroke on the rhythm strip. The scar on the chest is suggestive of pacer implantation but not definitive. There should be no change in pulse quality, and no vibration under the skin.
The nurse is speaking with a client admitted with a dysrhythmia. The client asks the nurse to explain the "F waves" on the electrocardiogram. What is the nurse's best response?
"The F waves are flutter waves representing atrial activity." F waves are flutter waves representing atrial activity. F waves are not representative of ventricular activity, nor are they normal parts of the heart's conduction system. F waves can be caused by chronic pulmonary disease, valvular disease, thyrotoxicosis, and open heart surgery; they are not caused by medication.
The nursing student asks the nurse to describe the difference between sinus rhythm and sinus bradycardia on the electrocardiogram strip. What is the nurse's best reply?
"The only difference is the heart rate." All characteristics of sinus bradycardia are the same as those of normal sinus rhythm except for the rate, which will be below 60 in sinus bradycardia. The P waves will be shaped differently in other dysrhythmias. The QRS is the same voltage for sinus rhythms. The P-R interval is prolonged in atrioventricular blocks.
The client asks the nurse to explain what is meant by a ventricular bigeminy cardiac rhythm. What is the best response by the nurse?
"The rhythm has a normal beat, then a premature beat pattern." Bigeminy is a rhythm in which every other complex is a premature ventricular contraction (PVC). In trigeminy, every third complex is a PVC. The rhythm is not regular and the rate should not be 150-250 bpm.
The client asks the nurse to explain what is meant by a ventricular bigeminy cardiac rhythm. What is the best response by the nurse?
"The rhythm has a normal beat, then a premature beat pattern." Bigeminy is a rhythm in which every other complex is a premature ventricular contraction (PVC). In trigeminy, every third complex is a PVC. The rhythm is not regular and the rate should not be 150-250 bpm.
The nurse is defibrillating a patient in ventricular fibrillation with paddles on a monophasic defibrillator. How much paddle pressure should the nurse apply when defibrillating?
20 to 25 lbs When using paddles, 20 to 25 lb of pressure must be used in order to ensure good skin contact.
The nurse is assigned the following client assignment on the clinical unit. For which client does the nurse anticipate cardioversion as a possible medical treatment?
A client with atrial arrhythmias The nurse is correct to identify a client with atrial arrhythmias as a candidate for cardioversion. The goal of cardioversion is to restore the normal pacemaker of the heart, as well as, normal conduction. A client with a myocardial infarction has tissue damage. The client with poor perfusion has circulation problems. The client with heart block has an impairment in the conduction system and may require a pacemaker.
The nurse is caring for a client who is displaying a third-degree AV block on the EKG monitor. What is the priority nursing intervention for the client?
Alerting the healthcare provider of the third-degree heart block The client may experience low cardiac output with third-degree AV block. The healthcare provider needs to intervene to preserve the client's cardiac output. Monitoring the blood pressure and heart rate are important, but not the priority. The identification of a code status during a heart block is not appropriate. The IV fluids are not helpful if the heart is not perfusing.
Which of the following medication classifications is more likely to be expected when the nurse is caring for a client with atrial fibrillation?
Anticoagulant Clients with persistent atrial fibrillation are prescribed anticoagulation therapy to reduce the risk of emboli formation associated with ineffective circulation. The other options may be prescribed but not expected in most situations.
Which of the following medication classifications is more likely to be expected when the nurse is caring for a client with atrial fibrillation?
Anticoagulant Clients with persistent atrial fibrillation are prescribed anticoagulation therapy to reduce the risk of emboli formation associated with ineffective circulation. The other options may be prescribed but not expected in most situations.
The nurse cares for a client with a dysrhythmia and understands that the P wave on an electrocardiogram (ECG) represents which phase of the cardiac cycle?
Atrial depolarization The P wave represents atrial depolarization. The QRS complex represents ventricular depolarization. The T wave represents ventricular repolarization. The ST segment represents early ventricular repolarization, and lasts from the end of the QRS complex to the beginning of the T wave.
A client presents to the emergency department via ambulance with a heart rate of 210 beats/minute and a sawtooth waveform pattern per cardiac monitor. The nurse is most correct to alert the medical team of the presence of a client with which disorder?
Atrial flutter Atrial flutter is a disorder in which a single atrial impulse outside the SA node causes the atria to contract at an exceedingly rapid rate. The atrioventricular (AV) node conducts only some impulses to the ventricle, resulting in a ventricular rate slower than the atrial rate, thus forming a sawtooth pattern on the heart monitor. Asystole is the absence of cardiac function and can indicate death. Premature ventricular contraction indicates an early electric impulse and does not necessarily produce an exceedingly rapid heart rate. Ventricular fibrillation is the inefficient quivering of the ventricles and indicative of a dying heart
The nurse is providing discharge instructions to a client after a permanent pacemaker insertion. Which safety precaution will the nurse communicate to the client?
Avoid undergoing magnetic resonance imaging (MRI). A client with a pacemaker should avoid undergoing an MRI because the magnet could disrupt pacemaker function and cause injury to the client. Disruption is less likely to occur with newer microwave ovens. The client must avoid vigorous arm and shoulder movement only for the first 6 weeks after pacemaker implantation. Airport metal detectors don't harm pacemakers; however, the client should notify airport security guards that he has a pacemaker because its metal casing and programming magnet could trigger the metal detector.
A nurse provides morning care for a client in the intensive care unit (ICU). Suddenly, the bedside monitor shows ventricular fibrillation and the client becomes unresponsive. After calling for assistance, what action should the nurse take next?
Begin cardiopulmonary resuscitation In the acute care setting, when ventricular fibrillation is noted, the nurse should call for assistance and defibrillate the client as soon as possible. If defibrillation is not readily available, CPR is begun until the client can be defibrillated, followed by advanced cardiovascular life support (ACLS) intervention, which includes endotracheal intubation and administration of epinephrine. Electrical cardioversion is not indicated for a client in ventricular fibrillation.
A patient's electrocardiogram (ECG), which has been ordered stat, indicates that the patient is experiencing ventricular tachycardia (VT). Which of the following nursing diagnoses should the nurse prioritize in the immediate care of this patient?
Cardiac output (CO), decreased A patient in VT is experiencing a medical emergency; decreased CO is the priority for intervention. Anxiety and knowledge deficit are valid diagnoses but would be superseded by the importance of promoting CO. Dysreflexia is not a relevant nursing diagnosis for this patient.
After evaluating a client for hypertension, a health care provider orders atenolol, 50 mg P.O. daily. Which therapeutic effect should atenolol have in treating hypertension?
Decreased cardiac output and decreased systolic and diastolic blood pressure As a long-acting, selective beta1-adrenergic blocker, atenolol decreases cardiac output and systolic and diastolic blood pressure; however, like other beta-adrenergic blockers, it increases peripheral vascular resistance at rest and with exercise. Atenolol may cause bradycardia, not tachycardia.
A critical care nurse is part of the code blue response team at the hospital and has been paged to the emergency department where a patient's condition has rapidly decompensated into ventricular fibrillation (VF). The nurse should prepare to assist with which of the following interventions?
Defibrillation VF necessitates prompt defibrillation. Cardioversion is not possible, due to the absence of an identifiable rhythm. Metoprolol and digoxin are not priority treatments for VF.
The nurse is assessing a patient with a probable diagnosis of first-degree AV block. The nurse is aware that this dysrhythmia is evident on an ECG strip by what indication?
Delayed conduction, producing a prolonged PR interval First-degree AV block may occur without an underlying pathophysiology, or it can result from medications or conditions that increase parasympathetic tone. It occurs when atrial conduction is delayed through the AV node, resulting in a prolonged PR interval.
The nurse is observing the monitor of a patient with a first-degree atrioventricular (AV) block. What is the nurse aware characterizes this block?
Delayed conduction, producing a prolonged PR interval First-degree AV block occurs when all the atrial impulses are conducted through the AV node into the ventricles at a rate slower than normal. Thus the PR interval is prolonged (>0.20 seconds).
Which of the following does the nurse recognize as the therapeutic goal of radiofrequency catheter ablation for a client with cardiac arrhythmias?
Destruction of errant tissue 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.
The nurse is caring for a client with a cardiac arrhythmia whose cardiac function is being continuously monitored. In which order will the nurse analyze the rhythm strip?
Determine the ventricular rate. Determine the ventricular rhythm. Determine the QRS duration. Determine consistency of the QRS duration. Identify the shape of the QRS. Identify P waves and presence before QRS complexes. Identify P wave consistency and shape. Determine the atrial rate. Determine the atrial rhythm Determine the PR interval for consistency and number for each QRS complex When evaluating the cardiac rhythm of a client with an arrhythmia, the ventricular rate should be first determined, followed by the ventricular rhythm. The QRS duration is reviewed next and analyzed for duration, consistency, and shape. This is followed by analysis of the P waves, specifically the location before every QRS complex, and the shape and consistency. Atrial rate and rhythm are next evaluated. This is followed by analysis of the PR interval to determine if they are consistent. The last step is to determine the number of P waves that occur for each QRS complex.
A client has been living with an internal, fixed-rate pacemaker. When checking the client's readings on a cardiac monitor the nurse notices an absence of spikes. What should the nurse do?
Double-check the monitoring equipment. One of the reasons for lack of pacemaker spikes is faulty monitoring equipment.
The nurse is preparing a client for upcoming electrophysiology (EP) studies and possible ablation for treatment of atrial tachycardia. What information will the nurse include in the teaching?
During the procedure, the dysrhythmia will be reproduced under controlled conditions. During EP studies, the patient is awake and may experience symptoms related to the dysrhythmia. The client does not receive general anesthesia. The EP procedure time is not easy to determine. EP studies do not always include ablation of the dysrhythmia.
The nurse assesses a client returning from the post anesthesia unit with a new onset of sinus tachycardia with a heart rate of 138 beats per minute and a blood pressure of 128/80mmHg after elevating the head of the bed. What intervention does the nurse consider?
Evaluating laboratory values Evaluating laboratory values such as complete blood count for anemia is an appropriate intervention because the anemia will cause tachycardia. Treating autonomic dysfunction or postural orthostatic tachycardia includes increasing intravenous fluid and applying anti-embolism stockings. Hypoglycemia is associated with bradycardia.
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 capture 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.
The nurse reads an athletic client's electrocardiogram. What finding will be consistent with a sinus bradycardia?
Heart rate of 42 beats per minute (bpm). The heart rate of 42 bpm is slow but normal when it occurs in athletes with a sinus bradycardia. The PR interval is prolonged at 0.24 seconds, indicating a heart block. The QR interval is prolonged and indicates ventricular delay. The ratio of P to QR should be 1:1 in sinus bradycardia.
The nurse identifies which of the following as a potential cause of premature ventricular complexes (PVCs)?
Hypokalemia PVCs can be caused by cardiac ischemia or infarction, increased workload on the heart (e.g., exercise, fever, hypervolemia, heart failure, tachycardia), digitalis toxicity, acidosis, or electrolyte imbalances, especially hypokalemia.
A client is treated in the intensive care unit (ICU) following an acute myocardial infarction (MI). During the nursing assessment, the client reports shortness of breath and chest pain. In addition, the client's blood pressure (BP) is 100/60 mm Hg with a heart rate (HR) of 53 bpm, and the electrocardiogram (ECG) tracing shows more P waves than QRS complexes. Which action should the nurse complete first?
Initiate transcutaneous pacing The client is experiencing a third-degree heart block. Transcutaneous pacing should be implemented first. A permanent pacemaker may be indicated if the block continues. Defibrillation is not indicated; third-degree heart block does not respond to atropine; a 12-lead ECG may be obtained, but is not completed first.
Which nursing intervention is required to prepare a client with cardiac dysrhythmia for an elective electrical cardioversion?
Instruct the client to restrict food and oral intake The nurse should instruct the client to restrict food and oral intake before the cardioversion procedure. Digitalis and diuretics are withheld for 24 to 72 hours before cardioversion. The presence of digitalis and diuretics in myocardial cells decreases the ability to restore normal conduction and increases the chances of a fatal dysrhythmia developing after cardioversion. When the client is in cardiopulmonary arrest, the nurse should facilitate CPR until the client is prepared for defibrillation and not for cardioversion. Monitoring blood pressure every 4 hours is not required to prepare a client with cardiac dysrhythmia.
Which nursing intervention must a nurse perform when administering prescribed vasopressors to a client with a cardiac dysrhythmia?
Monitor vital signs and cardiac rhythm 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
A nurse notices on a cardiac monitor that a patient is exhibiting signs of ventricular tachycardia (VT). The nurse knows to assess several factors prior to treatment (rhythm, existence of a prolonged QT interval, heart function). The nurse determines that the patient is stable. Select all the activities that the nurse should do.
Obtain an ECG reading to identify the rhythm. Call for an alert provider. Ensure adequate IV access. Apply supplemental oxygen. Defibrillation is only used for patients who don't have a pulse. The nurse should continue to assess and prepare the patient for additional interventions if VT progresses into ventricular fibrillation or the patient loses consciousness.
To evaluate a client's atrial depolarization, the nurse observes which part of the electrocardiogram waveform?
P wave The P wave depicts atrial depolarization, or spread of the electrical impulse from the sinoatrial node through the atria. The PR interval represents spread of the impulse through the interatrial and internodal fibers, atrioventricular node, bundle of His, and Purkinje fibers. The QRS complex represents ventricular depolarization. The T wave depicts the relative refractory period, representing ventricular repolarization.
A nursing instructor is reviewing the parts of an EKG strip with a group of students. One student asks about the names of all the EKG cardiac complex parts. Which of the following items are considered a part of the cardiac complex on an EKG strip? Choose all that apply.
P wave P-R interval T wave The EKG cardiac complex waves include the P wave, the QRS complex, the T wave, and possibly the U wave. The intervals and segments include the PR interval, the ST segment, and the QT interval. NOT QRT wave or SQ segment
The nurse is assessing vital signs in a patient with a permanent pacemaker. What should the nurse document about the pacemaker?
Pacer rate After a permanent pacemaker is inserted, the patient's heart rate and rhythm are monitored by ECG.
Undersensing occurs as a pacemaker malfunctions. The nurse understands undersensing occurs as a result of which event?
Pacing spike occurs at the preset level 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.
A client admitted to the telemetry unit has a serum potassium level of 6.6 mEq/L. Which electrocardiographic (ECG) characteristic is commonly associated with this laboratory finding?
Peaked T waves The client's serum potassium level is high. 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 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 P wave is an ECG characteristic reflecting conduction of an electrical impulse through the atria and is not affected by a client's serum potassium level. The QT interval is an ECG characteristic reflecting the time from ventricular depolarization to repolarization, and is not affected by a client's serum potassium level.
A patient with a history of acute coronary syndrome is having an electrocardiogram (ECG). When interpreting the ECG for potential signs of cardiac ischemia, the nurse should focus on which of the following waveforms and intervals?
ST segment ST segment changes are associated with ischemia and cardiac injury. A U wave is not always present, and the P wave represents atrial depolarization. The character of the QT interval is not a primary indicator of cardiac ischemia or injury.
The nurse is teaching a beginning EKG class to staff nurses. As the nurse begins to discuss the parts of the EKG complex, one of the students asks what the normal order of conduction through the heart is. What order does the nurse describe?
Sinoatrial (SA) node, atrioventricular (AV) node, bundle of His, right and left bundle branches, and the Purkinje fibers
Which dysrhythmia is common in older clients?
Sinus bradycardia Sinus bradycardia and atrial fibrillation are common dysrhythmia'a in older clients. Sinus tachycardia, sinus arrhythmmai, and ventricular tachycardia are not common dysrhythmias in older clients.
A patient comes to the emergency department with reports of chest pain after using cocaine. The nurse assesses the patient and obtains vital signs with results as follows: blood pressure 140/92, heart rate 128, respiratory rate 26, and an oxygen saturation of 98%. What rhythm on the monitor does the nurse anticipate viewing?
Sinus tachycardia Sinus tachycardia occurs when the sinus node creates an impulse at a faster-than-normal rate. Causes include medications that stimulate the sympathetic response (e.g., catecholamines, aminophylline, atropine), stimulants (e.g., caffeine, nicotine), and illicit drugs (e.g., amphetamines, cocaine, Ecstasy).
The licensed practical nurse is co-assigned with a registered nurse in the care of a client admitted to the cardiac unit with chest pain. The licensed practical nurse is assessing the accuracy of the cardiac monitor, which notes a heart rate of 34 beats/minute. The client appears anxious and states not feeling well. The licensed practical nurse confirms the monitor reading. When consulting with the registered nurse, which of the following is anticipated?
The registered nurse administering atropine sulfate intravenously The licensed practical nurse and registered nurse both identify that client's bradycardia. Atropine sulfate, a cholinergic blocking agent, is given intravenously (IV) to increase a dangerously slow heart rate. Lanoxin is not administered when the pulse rate falls under 60 beats/minute. It is dangerous to wait until the pulse rate increases without nursing intervention or administering additional medications until the imminent concern is addressed.
A client's Holter monitor strip reveals a heart rate with normal conduction but with a rate consistently above 105 beats/minute. What other conditions can cause this response in a healthy heart?
There are a variety of causes that can create an elevated heart rate in an otherwise healthy heart, including fever, shock, and strenuous exercise.
A patient has returned to the cardiac care unit after undergoing cardioversion. When providing care for this patient during the immediate recovery period, the nurse should prioritize assessments related to:
Thromboembolism When the heart returns to a normal sinus rhythm after cardioversion, the atria beat forcefully. If a clot has formed in the atria, systemic emboli may result, thus anticoagulation is needed if the arrhythmia has lasted over 48 hours. The nurse is alert for systemic signs of embolization such as sudden onset shortness of breath with pulmonary emboli or neurological changes. Sensory changes, renal failure, and infection are unlikely complications of cardioversion.
A patient who had a myocardial infarction is experiencing severe chest pain and alerts the nurse. The nurse begins the assessment but suddenly the patient becomes unresponsive, no pulse, with the monitor showing a rapid, disorganized ventricular rhythm. What does the nurse interpret this rhythm to be?
Ventricular fibrillation The most common dysrhythmia in patients with cardiac arrest is ventricular fibrillation, which is a rapid, disorganized ventricular rhythm that causes ineffective quivering of the ventricles. No atrial activity is seen on the ECG. The most common cause of ventricular fibrillation is coronary artery disease and resulting acute myocardial infarction. Ventricular fibrillation is always characterized by the absence of an audible heartbeat, a palpable pulse, and respirations.
A patient with hypertension has a newly diagnosed atrial fibrillation. What medication does the nurse anticipate administering to prevent the complication of atrial thrombi?
Warfarin Because atrial function may be impaired for several weeks after cardioversion, warfarin is indicated for at least 4 weeks after the procedure. Patients may be given amiodarone, flecainide, ibutilide, propafenone, or sotalol prior to cardioversion to enhance the success of cardioversion and prevent relapse of the atrial fibrillation (Fuster, Rydén et al., 2011).
The nurse is working with a client with a new onset of atrial fibrillation during a three-month follow-up visit. The healthcare provider is planning a cardioversion, and the client asks the nurse why there is a wait for the treatment. What is the best response by the nurse?
Your atrial chambers may contain blood clots now, so you must take an anticoagulant for a few weeks before the cardioversion Because of the high risk of embolization of atrial thrombi, cardioversion of atrial fibrillation that has lasted longer than 48 hours should be avoided unless the client has received warfarin for at least 3 to 4 weeks prior to cardioversion. The doctor will not wait for a change in rhythm. Resting the heart will not change the rhythm. There is no delay but safer for the clots to be dissolved with the anticoagulant.
A client has a medical diagnosis of an advanced first-degree atrioventricular block and is symptomatic. What initial treatment will the nurse be prepared to complete?
administer an IV bolus of atropine The initial treatment of choice is an IV bolus of atropine. If the client does not respond to atropine, has advanced AV block, or has had an acute MI, temporary pacing may be started. A permanent pacemaker my be necessary if the block persists. Cardioversion is done with a fast heart rate. Furosemide will be given for fluid overload. Cardiac catheterization is administered for chest pain.
The nurse is caring for a client with second-degree atrioventricular block, Type I with symptomatic bradycardia. What is the most likely medication the nurse will administer?
atropine sulfate Atropine blocks acetylcholine at parasympathetic neuroeffector sites and blocks vagal stimulation. The client will be treated with an anticholinergic that blocks the effects of the vagal nerve. Atenolol and nadolol are beta blockers that are used for chest pain, myocardial infarction, and hypertension. Diltiazem is a calcium channel blocker used to treat angina or slow the heart rate.
A client tells the nurse "my heart is skipping beats again; I'm having palpitations." After completing a physical assessment, the nurse concludes the client is experiencing occasional premature atrial complexes (PACs). The nurse should instruct the client to
avoid caffeinated beverages. If premature atrial complexes (PACs) are infrequent, no medical interventions are necessary. Causes of PACs include caffeine, alcohol, nicotine, stretched atrial myocardium (e.g., as in hypervolemia), anxiety, hypokalemia (low potassium level), hypermetabolic states (e.g., with pregnancy), or atrial ischemia, injury, or infarction. The nurse should instruct the client to avoid caffeinated beverages.
Which is not a likely origination point for cardiac arrhythmias?
bundle of His Cardiac arrhythmias may originate in the atria, atrioventricular node, or ventricles. They do not originate in the Bundle of His.
When the appropriate electrocardiogram (ECG) complex follows the pacing spike, it is said to be
captured 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.
The nurse witnesses a client experiencing ventricular fibrillation. What is the nurse's priority action?
defibrillation Advanced cardiac life support recommends early defibrillation for witnessed ventricular fibrillation. A cardioversion is used with a client who has a pulse. Atropine is used for bradycardia and dobutamine is an inotropic medication used to increased cardiac output.
The nurse assesses a client with a heart rate of 120 beats per minute. What are the known causes of sinus tachycardia?
hypovolemia The causes of sinus tachycardia include physiologic or psychological stress (acute blood loss, anemia, shock, hypovolemia, fever, and exercise). Vagal stimulation, hypothyroidism, and digoxin will cause a sinus bradycardia.
A client with dilated cardiomyopathy is having frequent episodes of ventricular fibrillation. What medical treatment does the nurse anticipate the client will have to terminate the episode of ventricular fibrillation?
internal cardioverter defibrillator insertion The implantable cardioverter defibrillator (ICD) is an electronic device that detects and terminates life-threatening episodes of tachycardia or fibrillation, especially those that are ventricular in origin. Patients at high risk of ventricular tachycardia (VT) or ventricular fibrillation who would benefit from an ICD are those who have survived sudden cardiac death syndrome, which usually is caused by ventricular fibrillation, or who have experienced spontaneous, symptomatic VT (syncope secondary to VT) not due to a reversible cause (called a secondary prevention intervention). Radiofrequency ablation destroys a small area of heart tissue that is causing rapid and irregular heartbeats, and is used to reduce pain. A cardiac electrophysiology study is an invasive procedure that tests the electrical conduction system of the heart to assess the electrical activity and conduction pathways of the heart.
