Week 4 - Dysrhythmias
A patient has been advised to have a permanent pacemaker implanted. What are the correct indications for a permanent pacemaker? Select all that apply. 1. Cardiomyopathy 2. SA node dysfunction 3. Coronary angioplasty 4. Drug therapy that may cause bradycardia 5. Third-degree atrioventricular (AV) block
Answer: 1, 2, 5 A permanent pacemaker helps to maintain the normal cardiac pace and is implanted within the body. The power source of such a device is placed subcutaneously, usually over the pectoral muscle on the patient's nondominant side. The permanent pacemaker is used in cardiomyopathy, SA node dysfunction, and third-degree AV block when the dysfunction of the electrical pathways is assumed to be permanent or irreversible. A temporary pacemaker may be required during coronary angioplasty and during drug therapy that may cause bradycardia. To maintain adequate cardiac rhythms during postoperative recovery and as a prophylactic measure after open heart surgery, temporary pacemakers are used. Text Reference - p. 804
The nurse responds to a cardiac monitor alarm and notes that the atrial flutter has developed. The patient is responsive, awake, and sitting up in bed. Which action should the nurse take first? 1. Assessing the patient for dyspnea 2. Initiating cardiopulmonary resuscitation 3. Preparing for synchronized cardioversion 4. Placing the patient in the Tredenlenburg position
Answer: 1. Assessing the patient for dyspnea Because the patient is awake and responsive, the next action should be to further assess him for stability and the possible cause of the dysrhythmia. The nurse should focus the assessment on vital signs such as blood pressure, heart rate, and respiratory status. Initiating cardiopulmonary resuscitation or preparing for synchronized cardioversion would only be an option if the patient were unstable. The Trendelenburg position is inappropriate for a patient with atrial flutter. Text Reference - p. 796
The nurse is preparing a patient for electrocardiogram (ECG). When placing the six unipolar chest leads, at what position should the nurse place the V6 lead? 1. Fifth intercostal space at the left midaxillary line 2. Fifth intercostal space at the left midclavicular line 3. Fifth intercostal space at the left anterior axillary line 4. Fourth intercostal space at the right sternal border
Answer: 1. Fifth intercostal space at the left midaxillary line The V6 lead should be placed at the fifth intercostal space at the left midaxillary line. The V4 lead is placed at the fifth intercostal space at the left midclavicular line. The V5 lead is placed at the fifth intercostal space at the left anterior axillary line. The V1 lead is placed at the fourth intercostal space at the right sternal border. Text Reference - p. 788
The patient has hypokalemia and the nurse obtains the following measurements on the rhythm strip: heart rate of 86 with a regular rhythm, P wave of 0.06 seconds and normal shape, PR interval of 0.24 seconds, and QRS of 0.09 seconds. How should the nurse document this rhythm? 1. First-degree atrioventricular (AV) block 2. Second-degree AV block 3. Premature atrial contraction (PAC) 4. Premature ventricular contraction (PVC)
Answer: 1. First-degree atrioventricular (AV) blocks In first degree AV block there is prolonged duration of AV conduction that lengthens the PR interval above 0.20 seconds. In type I second-degree AV block the PR interval continues to increase in duration until a QRS complex is blocked. In Type II the PR interval may be normal or prolonged, the ventricular rhythm may be irregular, and the QRS usually is greater than 0.12 seconds. PACs cause an irregular rhythm with a different shaped P wave than the rest of the beats and the PR interval may be shorter or longer. PVCs cause an irregular rhythm and the QRS complex is wide and distorted in shape. Text Reference - p. 795
A patient has sought care following a syncopal episode of unknown etiology. Which nursing action should the nurse prioritize in the patient's subsequent diagnostic workup? 1. Preparing to assist with a head-up tilt-test 2. Preparing an intravenous (IV) dose of a b-adrenergic blocker 3. Assessing the patient's knowledge of pacemakers 4. Teaching the patient about the role of antiplatelet aggregators
Answer: 1. Preparing to assist with a head-up tilt-test In patients without structural heart disease, the head-up tilt-test is a common component of the diagnostic workup following episodes of syncope. IV b -blockers are not indicated, although an IV infusion of low-dose isoproterenol may be started in an attempt to provoke a response if the head-up tilt-test did not have a response. Addressing pacemakers is premature and inappropriate at this stage of diagnosis. Patient teaching surrounding antiplatelet aggregators is not directly relevant to the patient's syncope at this time. Text Reference - p. 807
A nurse is preparing to complete an electrocardiogram (ECG) for a patient. The nurse observes artifact on the monitor. What could be a cause of artifact? Select all that apply. 1. The patient has dry skin 2. The patient is shivering 3. The conductive gel is still moist 4. Electrical interference is present 5. The leads and electrodes are not secure
Answer: 2, 4, 5 Muscle activity caused by shivering of the patient, electrical interference, or loose leads and electrodes can cause distorted baseline and waveforms called artifact on the electrocardiogram (ECG). Oily skin is wiped dry with alcohol to prepare the patient for ECG. Electrodes may have to be replaced if conductive gel has dried out. Text Reference - p. 790
The nurse is attending to a patient with second degree atrioventricular (AV) block. The patient is scheduled for pacemaker implantation. What instructions should a nurse give to the patient? Select all that apply. 1. Bathe after the implantation 2. Avoid direct blows to the incision site 3. Perform shoulder exercises 4. Monitor pulse and inform the cardiologist if it drops 5. Use microwave ovens when required
Answer: 2, 4, 5 The patient should avoid direct blows to the incision site for safety reasons. The patient should monitor pulse and inform the cardiologist if it drops below the predetermined rate. Microwave ovens are safe to use and do not interfere with the functioning of the pacemaker. Also, the incision site should be kept dry for 4 days after implantation, so bathing should be avoided. The patient should avoid lifting the arm above the shoulder until approved by the cardiologist, as it might affect the functioning of the pacemaker. Text Reference - p. 806
A nurse is attending to a patient admitted with sinus bradycardia. What could be the probable causes of bradycardia in the patient? Select all that apply. 1. Hyperthyroidism 2. Increased intracranial pressure 3. Hyperglycemia 4. Hypothermia 5. Calcium channel blockers
Answer: 2, 4, 5 The possible causes of sinus bradycardia include increased intracranial pressure, hypothermia, and treatment with calcium channel blockers. Increased intracranial pressure may suppress the cardiac centers in the brain, thus reducing the heart rate. Hypothermia may cause reduced venous return, thereby causing bradycardia. Calcium channel blockers cause bradycardia by decreasing automaticity of the SA node, and delaying the AV node conduction. The drug also reduces myocardial contractility. Hyperthyroidism increases the levels of thyroid hormone and increases the metabolism, resulting in tachycardia. Hyperglycemia causes tachycardia by causing systemic dehydration and acidosis. Text Reference - p. 793
The nurse is watching the cardiac monitor, and a patient's rhythm suddenly changes. There are no P waves. Instead there are fine, wavy lines between the QRS complexes. The QRS complexes measure 0.08 sec (narrow), but they occur irregularly with a rate of 120 beats/min. The nurse correctly interprets this rhythm as what? 1. Sinus tachycardia 2. Atrial fibrillation 3. Ventricular fibrillation 4. Ventricular tachycardia
Answer: 2. Atrial fibrillation Atrial fibrillation is represented on the cardiac monitor by irregular R-R intervals and small fibrillatory (f) waves. There are no normal P waves because the atria are not contracting truly, just fibrillating. Sinus tachycardia is a sinus rate above 100 beats/minute with normal P waves. Ventricular fibrillation is seen on the ECG without a visible P wave, an unmeasureable heart rate, PR, or QRS, and the rhythm is irregular and chaotic. Ventricular tachycardia is seen as three or more premature ventricular contractions (PVCs) that have distorted QRS complexes with regular or irregular rhythm; the P wave usually is buried in the QRS complex without a measureable PR interval. Text Reference - p. 795
The nurse prepares to deliver an electrical shock to a patient in a cardiac crisis. The nurse knows that defibrillation differs from synchronized cardioversion in which of these aspects? 1. The patient will be sedated before defibrillation is initiated 2. Defibrillation is the treatment of choice to end ventricular fibrillation 3. Synchronized cardioversion is indicated to treat atrial bradydysrhythmias 4. Defibillation is synchronized to deliver a shock during the QRS complex.
Answer: 2. Defibrillation is the treatment of choice to end ventricular fibrillation Defibrillation is the treatment of choice to end ventricular fibrillation and pulseless ventricular tachycardia. Synchronized cardioversion is the therapy of choice for the patient with hemodynamically unstable ventricular or supraventricular tachydysrhythmias. Defibrillation is not synchronized to deliver a shock during the QRS complex, nor is the patient sedated for defibrillation (a patient in ventricular tachycardia [VT] or pulseless VT will generally be unconscious). Text Reference - p. 802
The patient is admitted with acute coronary syndrome (ACS). The ECG shows ST segment depression and T wave inversion. What should the nurse know that this indicates? 1. Myocardial injury 2. Myocardial ischemia 3. Myocardial infarction 4. A pacemaker is present
Answer: 2. Myocardial ischemia The ST depression and T wave inversion on the ECG of a patient diagnosed with ACS indicate myocardial ischemia from an inadequate supply of blood and oxygen to the heart. Myocardial injury is identified with ST-segment elevation. Myocardial infarction is identified with ST-segment elevation and a widened and deep Q wave. A pacemaker's presence is evident on the ECG by a spike leading to depolarization and contraction. Text Reference - p. 806
A patient has a heart rate of 150 beats per minute. An electrocardiogram shows a normal P wave preceding each QRS complex. The nurse recognizes that the patient is most likely experiencing what condition? 1. Atrial fibrillation 2. Sinus tachycardia 3. Ventricular fibrillation 4. Premature atrial contraction
Answer: 2. Sinus tachycardia Sinus tachycardia inhibits the vagus nerve or stimulates the sympathetic nervous system. This causes an increase in the heart rate to about 101 beats to 200 beats per minute. The electrocardiographic study of sinus tachycardia shows a normal P wave preceding each QRS complex with normal time and duration. In atrial fibrillation, the P waves are chaotic and fibrillatory and the QRS complex is normal. The electrocardiographic study of ventricular fibrillation elicits the absence of P waves and the PR interval and QRS interval cannot be measured. In premature atrial contraction, there are distorted P waves in the ECG. Text Reference - p. 793
What should a nurse advise a group of caregivers with regard to a patient with an implantable cardioverter-defibrillator (ICD)? Select all that apply. 1. Restrict air travel 2. Restrict driving 3. Report any signs of infection at incision site 4. Restrict magnetic resonance imaging (MRI) scan 5. Restrict the lifting of arm on ICD side unless approved
Answer: 3, 4, 5 The patient with ICD should immediately report any signs of infection such as redness, swelling, drainage, or fever. The patient should not undergo MRI scan unless the ICD is approved as MRI safe. Also, the arm on the ICD side should not be lifted above the shoulder unless approved by the cardiologist. Air travel is not restricted. However, while traveling, the patient should inform the airport security personnel about the presence of ICD because it may set off the metal detector. The patient should wear a Medic Alert ID or bracelet at all times. Text Reference - p. 803
The nurse is caring for a patient who is 24 hours post-pacemaker insertion. Which nursing intervention is most appropriate at this time? 1. Reinforcing the pressure dressing as needed 2. Encouraging range-of-motion exercises of the involved arm 3. Assessing the incision for any redness, swelling, or discharge 4. Applying wet-to-dry dressings every four hours to the insertion site
Answer: 3. Assessing the incision for any redness, swelling, or discharge. After pacemaker insertion, it is important for the nurse to observe signs of infection by assessing for any redness, swelling, or discharge from the incision site. The nonpressure dressing is kept dry until removed, usually 24 hours postoperatively. It is important for the patient to limit activity of the involved arm to minimize pacemaker lead displacement. Text Reference - p. 805
The nurse monitoring the electrocardiogram (ECG) of a patient with hyperthyroidism observes regular, sawtooth-shaped flutter waves with an atrial rate 250 beats/minute. How should the nurse document this pattern? 1. SInus bradycardia 2. Sinus tachycardia 3. Atrial flutter 4. Atrial fibrillation
Answer: 3. Atrial flutter Atrial flutter is an atrial tachydysrhythmia identified by flutter (F) waves, a sawtoothed pattern, with a 200-350 beats/minute atrial rate. In sinus bradycardia, the heart rate is less than 60 beats/minute, with regular rhythm and normal P waves. Sinus tachycardia is identified by 101-200 beats/minute, with regular rhythm and normal P waves. In atrial fibrillation, atrial rate is 350-600 beats/minute, with irregular rhythm, and fibrillatory (f) waves. Text Reference - p. 794
A patient complains of dizziness, shortness of breath, and heart palpitations. The electrocardiogram (ECG) tracing shows paroxysmal supraventricular tachycardia (PSVT). The primary health care provider has prescribed adenosine (Adenocard). Which statement is true about adenosine? 1. It is given as an intravenous push (IVP) over one to two minutes 2. It must be given through a central line 3. Expect a period of asystole to follow administration 4. Patient will not experience discomfort from the administration if given correctly.
Answer: 3. Expect a period of asystole to follow administration Adenosine stops PSVT by slowing the conduction through the AV node. Therefore, a brief period of asystole is common. Adenosine is given as an IVP over one to two seconds and then immediately followed by a rapid 20 mL normal saline flush. It may be given through a peripheral IV, but the site should be as close to the heart as possible because of its short half-life. Patients often complain of chest discomfort when the adenosine takes effect. Text Reference - p. 795
The nurse notes that a patient has a history of paroxysmal supraventricular tachycardia. What heart rate characterizes this dysrhythmia? 1. Slower than 60 beats/min 2. Between 60 and 100 beats/min 3. Between 100 and 150 beats/min 4. Between 150 and 220 beats/min
Answer: 4. Between 150 and 220 beats/min Paroxysmal supraventricular tachycardia (PSVT) is characterized by a heart rate of 150 to 220 beats/min. A heart rate of fewer than 60 beats/min is considered bradycardia. A rate of 100 beats/min is the upper limit for a normal heart rate, and a rate of 100 to 150 beats/min is the range for a sinus tachycardia. Text Reference - p. 795
A nurse completing an electrocardiogram (ECG) for a patient is aware that cardiac cells contain properties that enable the conduction system to start an electrical impulse. Which property of the heart enables the cardiac cells to respond mechanically to an impulse? 1. Automaticity 2. Excitability 3. Conductivity 4. Contractility
Answer: 4. Contractility Contractility enables the cardiac cells to respond mechanically to an impulse. Automaticity provides the ability to initiate an impulse spontaneously and continuously. Excitability enables the cardiac cells to be electrically stimulated. Conductivity allows transmission of an impulse along a membrane in an orderly manner. Text Reference - p. 2
A patient is experiencing atrial flutter. The nurse anticipates that what treatment will most likely be included in the patient's plan of care? 1. Anticholinergic drugs 2. Carotid massage 3. The Maze procedure 4. Radiofrequency catheter ablation
Answer: 4. Radiofrequency catheter ablation Radiofrequency catheter ablation is the most effective technique for the treatment of atrial flutter. It is performed in the electrophysiology study laboratory, and involves the introduction of a catheter in the right atrium. The tissue is targeted and destroyed by the application of low-voltage, high-frequency electrical impulses. The destruction of the tissue results in a normal sinus rhythm. Anticholinergic drugs would increase the heart rate and are thus not appropriate to treat atrial flutter. Carotid massage is a maneuver for vagal stimulation and is generally used for treating paroxysmal supraventricular tachycardia. The Maze procedure is performed to treat atrial fibrillations that are refractory to drugs, electrical conversion, and radiofrequency catheter ablation. Text Reference - p. 793
A nurse is monitoring a patient on a wireless electrocardiogram (ECG) monitor. Which observation is a cause for concern? 1. Upright P wave 2. Flat ST segment 3. Prolonged QT interval 4. Upright T wave
Answer: Prolonged QT interval Prolonged QT interval is a cause for concern. QT disturbance may be caused by drugs, electrolyte imbalances, and changes in heart rate. Upright P wave, flat ST segment, and upright T wave are normal findings. Text Reference - p. 791
A nurse is teaching a group of nursing students about nursing actions during an electrocardiographic (ECG) recording. Arrange the actions in their correct order.
The first step during the measurement of an ECG is to remove excess hair on the skin. The presence of hair may not facilitate the proper adherence of electrodes to the skin. This could interfere with the recording of the cardiac impulses. It is followed by wiping the skin with alcohol to remove dirt and oil, and gently rubbing with gauze until the skin becomes pale pink. Wiping of the skin is followed by attaching the electrodes to the patient at the designated areas. Artifact may occur for various reasons. This indicates deformity of baseline and waveforms on electrocardiograph. Text Reference - p. 790
