CH26: Clients with Cardiac Dyshythmias
The nurse is assessing vital signs in a patient with a permanent pacemaker. What should the nurse document about the pacemaker? 1) Model number 2) Date and time of insertion 3) Location of the generator 4) Pacer rate
Correct response : Pacer rate Explanation: After a permanent pacemaker is inserted, the patient's heart rate and rhythm are monitored by ECG.
The nurse working in the emergency department places a client in anaphylactic shock on a cardiac monitor and sees the cardiac rhythm shown. Which dysrythmia should the nurse document? 1) sinus rhythm 2) ventricular tachycardia 3) junctional rhythm 4) atrial fibrillation 4) ventricular asystole
Correct response: ventricular tachycardia Explanation: The dysrhythmia shown is ventricular tachycardia because it has more than 3 premature ventricular contractions. The ventricular rate is 100 to 200 bpm; the atrial rate depends on the underlying rhythm (e.g., sinus rhythm). The QRS duration is 0.12 seconds or more and has an abnormal shape. . Ventricular asystole is characterized by absent QRS complexes; this rhythm is referred to as flatline. Normal sinus rhythm is regular with with a ventricular and atrial rate of 60 to 100 bpm. The P-wave has a consistent shape and is always in front of the QRS. The PR interval is a consistent interval between 0.12 and 0.20 seconds, and the P:QRS ratio is 1:1. A junctional rhythm not caused by a complete heart block has a ventricular rate of 40 to 60 bpm and, if P waves are discernible, an atrial rate of 40 to 60 bpm. The ventricular and atrial rhythm are regular. If the P-wave is in front of the QRS, the PR interval is less than 0.12 seconds. The P:QRS ratio is 1:1 or 0:1. Atrial fibrillation is indicated by an atrial rate of 300 to 600 bpm; the ventricular rate is usually 120 to 200 bpm if untreated. Both the ventricular and atrial rhythm are highly irregular. P-waves will not be discernible; irregular undulating waves that vary in amplitude and shape are referred to as fibrillatory or f waves. The PR interval cannot be measured, and the P:QRS ratio is Many:1.
The nurse is caring for a client who is being discharged after insertion of a permanent pacemaker. Which question by the client indicates a need for clarification? 1) "I should avoid contact sports." 2) "I'll watch the incision for swelling or redness and will report if either occurs." 3) "I should avoid large magnetic fields, such as an MRI machine or large motors." 4) "I should ask for a handheld device search when I go through airport security."
Correct response: "I should ask for a handheld device search when I go through airport security." Explanation: At security gates at airports, government buildings, or other secured areas, the client with a permanent pacemaker should show a pacemaker ID card and request a hand (not handheld device) search. The client should obtain and carry a physician's letter about this requirement.
The nurse is providing teaching to a client with an implanted cardiac device. Which client statement indicates that teaching has been effective? 1) "I will stop using the microwave oven." 2) "I will not be able to fly with a pacemaker." 3) "I can safely have an MRI in the future if I need one." 4) "I will not place my cell phone in my chest pocket."
Correct response: "I will not place my cell phone in my chest pocket." Explanation: 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..
A patient is undergoing preoperative teaching before cardiac surgery. The nurse explains that a temporary pacemaker will be placed later that day, and it will be removed after the surgery. The patient asks the nurse what will happen if the pacemaker quits functioning. What is the nurse's best response? 1) "Monitoring for pacemaker malfunctioning and battery failure is something the technician down the hall does." 2) "Monitoring for pacemaker malfunctioning and battery failure is something the secretary at the nurse's station does." 3) "Monitoring for pacemaker malfunctioning and battery failure is something the health care provider caring for you does when he makes rounds every day." 4) "Monitoring for pacemaker malfunctioning and battery failure is something the nurse caring for you does."
Correct response: "Monitoring for pacemaker malfunctioning and battery failure is something the nurse caring for you does." Explanation: Monitoring for pacemaker malfunctioning and battery failure is a nursing responsibility.
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? 1) "The F waves are flutter waves representing atrial activity." 2) "The F waves are flutter waves representing ventricular activity." 3) "The F waves are normal parts of the heart conduction system" 4) "The F waves are most likely caused by the new medication."
Correct response: "The F waves are flutter waves representing atrial activity." Explanation: 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 how to tell the difference between ventricular tachycardia and ventricular fibrillation on an electrocardiogram strip. What is the best response? 1) "The two look very much alike; it is difficult to tell the difference." 2) "Ventricular fibrillation is irregular with undulating waves and no QRS complex. Ventricular tachycardia is usually regular and fast, with wide QRS complexes." 3) "The QRS complex in ventricular fibrillation is always narrow, while in ventricular tachycardia the QRS is of normal width." 4) "The P-R interval will be prolonged in ventricular fibrillation, while in ventricular tachycardia the P-R interval is normal."
Correct response: "Ventricular fibrillation is irregular with undulating waves and no QRS complex. Ventricular tachycardia is usually regular and fast, with wide QRS complexes." Explanation: Ventricular fibrillation is irregular with undulating waves and no QRS complex, while ventricular tachycardia is usually regular and fast with wide QRS complexes. The rhythms look different on the electrocardiogram strip. The QRS is wide and bizarre or undefined in ventricular fibrillation. The P-R interval is not present in the ventricular dysrhythmias.
The nurse is working on a telemetry unit, caring for a client who develops dizziness and a second-degree heart block, Mobitz Type 1. What will be the initial nursing intervention? 1) Send the client to the cardiac catheterization laboratory. 2) Prepare to client for cardioversion. 3) Administer an IV bolus of atropine. 4) Review the client's medication record.
Correct response: Administer an IV bolus of atropine. Explanation: Atropine 0.5 mg given rapidly as an intravenous bolus every 3 to 5 minutes to a maximum total dose of 3.0 mg is the medication of choice in treating symptomatic second-degree heart block. The client may need to be sent to the cardiac catheterization lab for a temporary pacemaker, but atropine should be tried first. Cardioversion is used to treat a fast heart rate. Reviewing the medication record will not help the client initially.
A client is brought to the ED and determined to be experiencing symptomatic sinus bradycardia. The nurse caring for this client is aware the medication of choice for treatment of this dysrhythmia is the administration of atropine. What guidelines will the nurse follow when administering atropine? 1) Administer atropine 0.5 mg as an IV bolus every 3 to 5 minutes to a maximum of 3.0 mg. 2) Administer atropine as a continuous infusion to a maximum of 30 mg in 24 hours. 3) Administer atropine 1.0 mg sublingually. 4) Administer atropine as a continuous infusion until symptoms resolve.
Correct response: Administer atropine 0.5 mg as an IV bolus every 3 to 5 minutes to a maximum of 3.0 mg. Explanation: Atropine 0.5 mg given rapidly as an intravenous (IV) bolus every 3 to 5 minutes to a maximum total dose of 3.0 mg is the medication of choice in treating symptomatic sinus bradycardia. By this guideline, the other listed options are inappropriate.
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? 1) Alerting the healthcare provider of the third-degree heart block 2) Assessing the client's blood pressure and heart rate frequently 3) Identifying the client's code level status 4) Maintaining the client's intravenous fluids
Correct response: Alerting the healthcare provider of the third-degree heart block Explanation: 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.
The nurse is monitoring a patient in the postanesthesia care unit (PACU) following a coronary artery bypass graft, observing a regular ventricular rate of 82 beats/min and "sawtooth" P waves with an atrial rate of approximately 300 beat/min. How does the nurse interpret this rhythm? 1) Ventricular tachycardia 2) Atrial flutter 3) Ventricular fibrillation 4) Atrial fibrillation
Correct response: 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. Because the atrial rate is faster than the AV node can conduct, not all atrial impulses are conducted into the ventricle, causing a therapeutic block at the AV node. This is an important feature of this dysrhythmia. If all atrial impulses were conducted to the ventricle, the ventricular rate would also be 250 to 400 bpm, which would result in ventricular fibrillation, a life-threatening dysrhythmia. Atrial flutter often occurs in patients with chronic obstructive pulmonary disease, pulmonary hypertension, valvular disease, and thyrotoxicosis, as well as following open heart surgery and repair of congenital cardiac defects (Fuster, Walsh et al., 2011).
A client has had a pacemaker implanted and the nurse will begin client education upon the client becoming alert. Which postimplantation instructions must be provided to the client with a permanent pacemaker? 1) Avoid sources of electrical interference. 2) Keep moving the arm on the side where the pacemaker is inserted. 3) Delay activities such as swimming and bowling for at least 3 weeks. 4) Keep the arm on the side of the pacemaker higher than the head.
Correct response: Avoid sources of electrical interference. Explanation: The nurse must instruct the client with a permanent pacemaker to avoid sources of electrical interference, such as MRI devices, large industrial motors, peripheral nerve stimulators, etc.
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? 1) Provide electrical cardioversion 2) Prepare for endotracheal intubation 3) Begin cardiopulmonary resuscitation 4) Administer intravenous epinephrine
Correct response: Begin cardiopulmonary resuscitation Explanation: 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 client has returned to the cardiac care unit after having a permanent pacemaker implantation. For which potential complication should the nurse most closely assess this client? 1) Malignant hyperthermia 2) Bradycardia 3) Bleeding at the implantation site 4) Chest pain
Correct response: Bleeding at the implantation site Explanation: Bleeding, hematomas, local infections, perforation of the myocardium, and tachycardia are complications of pacemaker implantations. The nurse should monitor for chest pain and bradycardia, but bleeding is a more common immediate complication. Malignant hyperthermia is unlikely because it is a response to anesthesia administration.
The nurse is caring for a client who has just undergone catheter ablation therapy. The nurse in the step-down unit should prioritize what assessment? 1) Monitoring the client's level of consciousness (LOC) 2) Cardiac monitoring 3) Pain assessment 4) Monitoring the implanted device signal
Correct response: Cardiac monitoring Explanation: Following catheter ablation therapy, the client is closely monitored to ensure the dysrhythmia does not reemerge. This is a priority over monitoring of LOC and pain, although these are valid and important assessments. Ablation does not involve the implantation of a device.
A client is admitted to the cardiac care unit for an electrophysiology (EP) study. What goal should guide the planning and execution of the client's care? 1) Determine the nursing plan of care. 2) Ablate the area causing the dysrhythmia. 3) Freeze hypersensitive cells. 4) Diagnose the dysrhythmia.
Correct response: Diagnose the dysrhythmia. Explanation: A client may undergo an EP study in which electrodes are placed inside the heart to obtain an intracardiac ECG. This is used not only to diagnose the dysrhythmia but also to determine the most effective treatment plan. However, because an EP study is invasive, it is performed in the hospital and may require that the client be admitted.
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? 1) Double-check the monitoring equipment. 2) Do nothing; there is no cause for alarm. 3) Measure the client's blood pressure. 4) Suggest the need for a new beta-blocker to the doctor.
Correct response: Double-check the monitoring equipment Explanation: One of the reasons for lack of pacemaker spikes is faulty monitoring equipment.
The nurse reads an athletic client's electrocardiogram. What finding will be consistent with a sinus bradycardia? 1) Heart rate of 42 beats per minute (bpm). 2) QR interval of 0.25 seconds. 3) P-to-QR ratio of 1:2. 4) PR interval of 0.24 seconds.
Correct response: Heart rate of 42 beats per minute (bpm). Explanation: 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 is assessing a client who had a pacemaker implanted 4 weeks ago. During the client's most recent follow-up appointment, the nurse identifies data that suggest the client may be socially isolated and depressed. What nursing diagnosis is suggested by these data? 1) Spiritual distress related to pacemaker implantation 2) Decisional conflict related to pacemaker implantation 3) Deficient knowledge related to pacemaker implantation 4) Ineffective coping related to pacemaker implantation
Correct response: Ineffective coping related to pacemaker implantation Explanation: Depression and isolation may be symptoms of ineffective coping with the implantation. These psychosocial symptoms are not necessarily indicative of issues related to knowledge or decisions. Further data would be needed to determine a spiritual component to the client's challenges.
Which nursing intervention is required to prepare a client with cardiac dysrhythmia for an elective electrical cardioversion? 1) Instruct the client to restrict food and oral intake 2) Monitor blood pressure every 4 hours 3) Facilitate CPR until the client is prepared for cardioversion 4) Administer digitalis and diuretics 24 hours before cardioversion
Correct response: Instruct the client to restrict food and oral intake Explanation: 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? 1) Keep the client flat for one hour after administration 2) Monitor vital signs and cardiac rhythm 3) Document heart rate before and after administration 4) Administer every five minutes during cardiac resuscitation
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.
To evaluate a client's atrial depolarization, the nurse observes which part of the electrocardiogram waveform? 1) T wave 2) QRS complex 3) P wave 4) PR interval
Correct response: P wave Explanation: 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.
The nursing educator is presenting a case study of an adult client who has abnormal ventricular depolarization. This pathologic change would be most evident in what component of the ECG? 1) QRS complex 2) U wave 3) T wave 4) P wave
Correct response: QRS complex Explanation: The QRS complex represents the depolarization of the ventricles and, as such, the electrical activity of that ventricle.
The nurse is caring for a client with refractory atrial fibrillation who underwent the maze procedure several months ago. The nurse reviews the result of the client's most recent cardiac imaging, which notes the presence of scarring on the atria. How should the nurse best interpret this finding? 1) Recognize that the procedure was unsuccessful. 2) Liaise with the care team in preparation for repeating the maze procedure. 3) Prepare the client for pacemaker implantation. 4) Recognize this as a therapeutic goal of the procedure.
Correct response: Recognize this as a therapeutic goal of the procedure. Explanation: The maze procedure is an open heart surgical procedure for refractory atrial fibrillation. Small transmural incisions are made throughout the atria. The resulting formation of scar tissue prevents reentry conduction of the electrical impulse. Consequently, scar formation would constitute a successful procedure. There is no indication for repeating the procedure or implanting a pacemaker.
A client has undergone diagnostic testing and received a diagnosis of sinus bradycardia attributable to sinus node dysfunction. When planning this client's care, which nursing diagnosis is most appropriate? 1) Risk for acute pain 2) Risk for fluid volume excess 3) Risk for activity intolerance 4) Risk for unilateral neglect
Correct response: Risk for activity intolerance Explanation: Sinus bradycardia causes decreased cardiac output that is likely to cause activity intolerance. It does not typically cause pain, fluid imbalances, or neglect of a unilateral nature.
The nurse is assisting with the monitoring of a client with a dysrhythmia that shows the pattern in the accompanying image. What dysrhythmia does the client have 1) Atrial fibrillation 2) Ventricular tachycardia 3) Sinus bradycardia 4) Sinus tachycardia
Correct response: Sinus bradycardia Explanation: In sinus bradycardia, the SA node initiates impulses at 40 to 60 times/min. In sinus tachycardia, the SA node initiates impulses at 100 to 150 times/min. In atrial fibrillation, there are no identifiable P waves. The atrial impulses look like a fine undulating line. Continuous generation of impulses results in ventricular tachycardia.
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? 1) Ventricular tachycardia 2) Normal sinus rhythm 3) Sinus bradycardia 4) Sinus tachycardia
Correct response: Sinus tachycardia Explanation: 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).
A client has been diagnosed with atrial fibrillation and has been prescribed warfarin therapy. What should the nurse prioritize when providing health education to the client? 1) The need to sit upright for 30 minutes after taking the medication 2) The need to have regular blood levels drawn 3) The importance of taking the medication 1 hour before or 2 hours after a meal 4) The importance of adequate fluid intake
Correct response: The need to have regular blood levels drawn Explanation: One drawback of warfarin therapy is the need to have blood levels drawn on a regular basis. The medication does not need to be taken on an empty stomach, and the client does not have to sit upright. Adequate fluid intake is useful in a general way, but the need for fluids is not increased by taking warfarin.
A patient has been admitted to the unit for an electrophysiology (EP) study. For what is an electrophysiology study primarily performed? 1) To facilitate cardioversion 2) To diagnose the dysrhythmia 3 To freeze hypersensitive cells 4) To determine the nursing plan of care
Correct response: To diagnose the dysrhythmia Explanation: A patient may undergo an EP study in which electrodes are placed inside the heart to obtain an intracardiac electrocardiogram (ECG). This is used not only to diagnose the dysrhythmia, but also to determine the most effective treatment plan. However, because an EP study is invasive, it is performed in the hospital and may require that the patient be admitted. The primary purpose of an EP is not freezing hypersensitive cells, facilitating cardioversion, or determining the plan of nursing care.
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? 1) Ventricular fibrillation 2) Atrial fibrillation 3) Ventricular tachycardia 4) Third-degree heart block
Correct response: Ventricular fibrillation Explanation: 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 client reports light-headedness, chest pain, and shortness of breath. They physician orders tests to ascertain what is causing the client's problems. Which test is used to identify cardiac rhythms? 1) echocardiogram 2) electrocautery 3) electroencephalogram 4) electrocardiogram
Correct response: electrocardiogram Explanation: An electrocardiogram is used to identify normal and abnormal cardiac rhythms.
The nurse assesses a client with a heart rate of 120 beats per minute. What are the known causes of sinus tachycardia? 1) vagal stimulation 2) hypothyroidism 3) digoxin 4) hypovolemia
Correct response: hypovolemia Explanation: 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 asks the nurse what causes the heart to be an effective pump. The nurse informs the client that this is due to the: 1) sufficient blood pressure. 2) inherent rhythmicity of all muscle tissue. 3) inherent electrons in muscle tissue. 4) inherent rhythmicity of cardiac muscle tissue.
Correct response: inherent rhythmicity of cardiac muscle tissue. Explanation: Cardiac rhythm refers to the pattern (or pace) of the heartbeat. The conduction system of the heart and the inherent rhythmicity of cardiac muscle produce a rhythm pattern, which greatly influences the heart's ability to pump blood effectively.
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? 1) radiofrequency ablation 2) electrophysiological study 3) pacemaker insertion 4) internal cardioverter defibrillator insertion
Correct response: internal cardioverter defibrillator insertion Explanation: 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.
A client has been using the recumbent bicycle as part of therapy after cardiac surgery. The client reports chest palpitations and fluttering. Which type of dysrhythmia might the client be experiencing? 1) tachyarrhythmia 2) sinus bradycardia 3) second degree heart block 4) first degree heart block
Correct response: tachyarrhythmia Explanation: Palpitations, or so-called heart fluttering, can be an indication of tachyarrhythmia. Palpitations or heart fluttering can be an indication of tachydysrhythmia, not sinus bradycardia. Heart blocks are more likely to cause bradycardia.
A client is diagnosed with sinus bradycardia. The nurse knows that the client's atrial rate is at or below what number?1
Correct response: 60 Explanation: Sinus bradycardia is a dysrhythmia that proceeds normally through the conduction pathway but at a slower than usual rate 60 beats/min or less.
The nurse is observing the monitor of a patient with a first-degree atrioventricular (AV) block. What is the nurse aware characterizes this block? 1) Delayed conduction, producing a prolonged PR interval 2) P waves hidden with the QRS complex 3) An irregular rhythm 4) A variable heart rate, usually fewer than 60 bpm
Correct response: Delayed conduction, producing a prolonged PR interval Explanation: 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).
When the appropriate electrocardiogram (ECG) complex follows the pacing spike, it is said to be 1) inhibited. 2) captured. 3) triggered. 4) 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.
A client experiences a faster-than-normal heart rate when drinking more than two cups of coffee in the morning. What does the nurse identify on the electrocardiogram as an indicator of sinus tachycardia? 1) PR interval of 0.1 seconds 2) Q wave of 0.04 seconds 3) QRS duration of 0.16 seconds 4) heart rate of 118 bpm
Correct response: heart rate of 118 bpm Explanation: The sinus node creates an impulse at a faster-than-normal rate. The PR interval of 0.1 seconds, QRS duration of 0.16 seconds and Q wave of 0.04 seconds are consistent with a normal sinus rhythm. Sinus tachycardia occurs when the heart rate is over 100 bpm.
