Chapter 26
Atrial Dysrhythmias Premature Atrial Complex
Occurs when an electrical impulse starts in the atrium before the next normal impulse of the sinus node.
The Five Steps to Rhythm Interpretation
1. Are there QRS complexes? Are they the same shape? 2. What's the regularity? 3. What's the heart rate? 4. Are there P waves? Are they the same shape? Are they in the same place relative to the QRS? Are any P waves not followed by a QRS? 5. What are the PR and QRS intervals?
Lead Placement
1.Clean the skin 2.Abrade the surface lightly 3.Attach "wires" to the "patches" 4.Pull disposable electrode pads from backing
Small box is how many seconds?
0.04
5 small boxes on a strip equal how long?
0.20 seconds
Sinus bradycardia
<60 Normal sinus rhythm
Sinus tachycardia
>100 (100-150) Normal sinus rhythm
Ventricular Fibrillation (VF) (Vfib) (looks like old school wood saw)
A life threatening emergency THE HEART DOES NOT CONTRACT - Rapid rate of electrical discharges from many irritable ventricular foci - Produces erratic, unrecognizable waves (fibrillation) (electrical chaos) - Ventricular rate 350-450/min•Ventricles provide no mechanical pumping Treatment is DEFIB. NEED TO RECOGNIZE THIS
Pacemaker rhythm
A pacemaker stimulates the atrium and ventricle sequentially mimicking normal cardiac physiology.
Torsades de pointes (looks like radio waves)
A polymorphic VT preceded by a prolonged QT interval Causes - Medications, low levels of potassium, calcium or magnesium Congenital QT prolongation Immediate treatment is necessary - IV Magnesium
Degree of Heart Blocks Third-Degree AV Block (Complete Heart Block)
Occurs when no atrial impulse is conducted through the AV node into the ventricles Two impulses are stimulating the heart: one stimulates the ventricle (QRS) and one stimulates the atria (P wave) AV dissociation P waves have nothing to do with the QRS
Degree of Heart Blocks Second Degree Atrioventricular Block, type II (Mobitz II)
Occurs when only some of the atrial impulses are conducted through the AV node into the ventricles. P-P and PR remain constant (where there is a QRS) R-R intervals are irregular as a QRS is not conducted with every P Ventricular rate is lower than atrial rate
35. The nurse is assessing a patient who had a pacemaker implanted 4 weeks ago. During the patients most recent follow-up appointment, the nurse identifies data that suggest the patient may be socially isolated and depressed. What nursing diagnosis is suggested by these data? A) Decisional conflict related to pacemaker implantation B). Deficient knowledge related to pacemaker implantation C). Spiritual distress related to pacemaker implantation D).Ineffective coping related to pacemaker implantation
Ans D Feedback: 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 patients challenges.
Degrees of Heart Blocks First Degree Atrioventricular Block (long PR)
All atrial impulses are conducted through AV node into the ventricles at a rate slower than normal. *****PR > 0.20 seconds
Sinus Bradycardia
Occurs when the SA node creates an impulse at a slower than normal rate. -Causes include lower metabolic needs; sleep, athlete at rest, hypothyroidism, vagal stimulation or medications -All characteristics the same as NSR except rate
Five Steps to Rhythm Interpretation What is not Normal?
Arrhythmia Abnormal heart rhythms will have some combination of the following: - QRS complexes absent or abnormally shaped - P waves absent, multiple in number, or abnormally shaped - Abnormally shortened or prolonged PR intervals - Abnormally prolonged QRS intervals - Heart rate abnormally slow or fast - Irregular rhythm or a rhythm interrupted by premature beats or pauses
What is the result of PVC's?
Clinical significance: - PVC following MI may lead to life threatening MI (V-tach, V-flutter, V-Fib) - If frequent, then there is more concern Treatment of PVC's Asymptomatic or No underlying HD.....Do not treat Symptomatic - Treat underlying cause (hypoxia, electrolyte imbalance, meds, MI, stress, stimulants) - Emergency- Amiodarone
Methods for Calculating Heart Rate The little block method
Count number of little blocks between QRS complexes. Divide into 1500, as there are 1,500 little blocks in one minute. Use this method to calculate the heart rate range in irregular rhythms Find the two consecutive QRS complexes that are the farthest apart from each other. - Calculate the heart rate there-that's the slowest rate. Find the two consecutive QRS complexes that are the closest together. - Calculate the heart rate there—that's the fastest rate.
What is an Implantable Cardioverter Defibrillator (ICD)
Device that detects and terminates life-threatening episodes of tachycardia and fibrillation such as: •Repeated episodes of V-Tach or V-Fib •Generator is designed to monitor and defibrillate Anti-tachycardia pacing - Comes with ICD identification card - No MRI's (newer models may be MRI compatible) - Avoid large electrical transformers and metal detectors - Have family learn CPR
Treatment process for V Fib if Defibrillation doesnt help
Epinephrine first. May repeat 3-5 mins later. If not effective, then use Amiodorone 300mg IV
Conduction Abnormalities
First-degree AV Block Second-degree AV Block, Type I (Wenckebach) Second-degree AV Block, Type II Third-degree AV Block
What are some complications of Pacemaker Use?
Infection Bleeding or hematoma formation Dislocation of lead Skeletal muscle or phrenic nerve stimulation Cardiac tamponade Pacemaker malfunction
Methods for calculating heart rate The 6-second strip method
Least accurate of all methods Can be misleading Count number of QRS complexes on six-second strip and multiply by 10. Provides a MEAN heart rate
6 second strip method
Least accurate. Count number of QRS complexes on 6-second strip and multiply by 10.
Atrial Fibrillation Medical Management
Medications: Antithrombotic medications to reduce stroke risk - Low risk of stroke - Aspirin 81 mg - 325 mg - Moderate risk of stroke - Warfarin, Xarelto, Eliquis Heart rate control medications - Beta Blocker, Ca Channel Blockers Medications that convert Heart rhythm or prevent Afib -(Amiodarone)
Deflections on the EKG
Positive deflection Isoelectric line Negative deflection
Normal Electrical Conduction
SA node (sinus node) Conduction - electrical impulse quickly travels from the SA node through to the Atria to the AV node AV node Bundle of His Right and left bundle branches Purkinje fibers Depolarization = stimulation = systole Repolarization = relaxation = diastole
5 Lead System Placement
See photo
Types of Dysrhythmias
Sinus -Sinus bradycardia -Sinus tachycardia Atrial -Premature atrial complex -Atrial flutter -Atrial fibrillation -SVT Ventricular -Premature ventricular complex -Ventricular tachycardia -Ventricular fibrillation -Ventricular asystole
Five Steps to Rhythm Interpretation What is Normal?
Sinus rhythm, the normal rhythm, has: - Narrow QRS complexes of uniform shape - Regularly spaced QRS complexes - Heart rate between 60-100 - Upright rounded matching P waves "married to" the QRS - PR interval of 0.12-0.20 seconds, constant from beat to beat - QRS interval of <0.12 seconds
Analyzing the ECG Rhythm Strip
Sinus rhythms are the standard against which all other rhythms are compared. Criteria for sinus rhythms: - Upright matching P waves in Lead II followed by a QRS and - PR intervals constant and Heart rate less than or equal to 160 at rest. All matching upright P waves in Lead II are considered sinus P waves until proven otherwise. Sinus node dysrhythmias - Sinus bradycardia - Sinus tachycardia
Adjunctive Modalities and Management
Used when medications alone are ineffective against: - Dysrhythmia - Pacemakers - Cardioversion - Defibrillation Nurse responsible for assessment of the patient's understanding regarding the mechanical therapy
When can you shock a person with defib
V tach and V fib
Methods for Calculating Heart Rate The Memory Method
Widely used in hospitals Fastest method 300 big blocks every minute Count the number of big blocks between consecutive QRS complexes and divide that number into 300. Memorize this sequence of numbers 300-150-100-75-60-50-43-37-33-30
What patient education is needed for post Pacemaker Insertion?
**Pulse monitoring, symptoms (hiccups) and reporting (know rate)** •Skin care •Pacer ID •No tight clothes •No pressure over generator •MRI ? (must be MRI compatible) •Electrical appliances with caution (microwaves) •Anti theft devices in stores are generally Ok •Airport screening
Heart Rate Determination
*Small Block Method*: - Count the number of small blocks between QRS complexes - Divide 1500 by that number
Supraventricular Tachycardia
- Catchall term for tachycardias that originate above the ventricles in either the sinus node, the atrium, or the AV Junction - Cannot discern exact origin because P waves are not discernible - Rate 130 or higher (usually >150) - Regular - P waves not discernible - cannot measure the PR QRS < 0.12 seconds Cause - Atria become "hyper" and fire early, before next sinus beat is due. Medications (stimulants, caffeine, bronchodilators), tobacco, hypoxia or heart disease. Treatment - Adenosine only for SVT (FIRST CHOICE and push as fast as you can), digitalis, calcium channel blockers, beta-blockers. Elective cardioversion can also be done if unstable ONLY FOR SVT TELL PATIENT TO BARE DOWN** (blowing a balloon or in a syringe)
Nursing Process: Care of the Patient with a Dysrhythmia— Assessment # 1
- Causes of dysrhythmia, contributing factors, the dysrhythmia's effect on the heart's ability to pump an adequate blood volume - Assess indicators of cardiac output and oxygenation - Health history: previous occurrences of decreased cardiac output, possible causes of the dysrhythmia - - All medications (prescribed and over-the-counter) - Psychosocial assessment: patient's "perception" of dysrhythmia
The Nursing Process: Care of the Patient With a Dysrhythmia Name some nursing diagnoses for dysthythmia?
- Decreased cardiac output related to inadequate ventricular filling or altered heart rate - Anxiety related to fear of the unknown outcome of altered health state - Deficient knowledge about the dysrhythmia and its treatment
After permanent electronic device is inserted, what do nurses assess for?
- ECG assessment - CXR Nursing assessment - CO and hemodynamic stability - Incision site - Signs of ineffective coping - Level of knowledge and education needs of family and patient
Asystole (Ventricular)
- Flat line EKG - All pacemakers have failed - Confirm in two or more leadsTreatment - High quality CPR with minimal interruptions - Identify underlying causes and contributing factors Key to successful treatment is a rapid assessment to identify possible cause known as Hs and Ts: hypoxia, hypovolemia, hydrogen ion(acid -base imbalance, hypo or hyper glycemia, hyperkalemia, hyperthermia, trauma, toxins, tamponade, tension pneumothorax or thrombus.
Ectopy
- Irritable tissues discharges before the SA node - Can be in different parts of heart, can make P and QRS look different. - After the premature complex, there is pause before next normal complex, creating irregularity in the rhythm.
Premature Ventricular Contractions (PVC's)
- Irritable ventricular foci - Conducts through the ventricle before the next sinus beat - QRS is wide (>.12) - Bigeminy, trigeminy, couplets (don't need to know) > 3 In a row is called baby V-Tach
15. The nurse and the other members of the team are caring for a patient who converted to ventricular fibrillation (VF). The patient was defibrillated unsuccessfully and the patient remains in VF. According to national standards, the nurse should anticipate the administration of what medication? A) Epinephrine 1 mg IV push B) Lidocaine 100 mg IV push C) Amiodarone 300 mg IV push D) Sodium bicarbonate 1 amp IV push
Ans: A Feedback: Epinephrine should be administered as soon as possible after the first unsuccessful defibrillation and then every 3 to 5 minutes. Antiarrhythmic medications such as amiodarone and licocaine are given if ventricular dysrhythmia persists.
21. A group of nurses are participating in orientation to a telemetry unit. What should the staff educator tell this class about ST segments? A) They are the part of an ECG that reflects systole. B) They are the part of an ECG used to calculate ventricular rate and rhythm. C) They are the part of an ECG that reflects the time from ventricular depolarization through repolarization. D) They are the part of an ECG that represents early ventricular repolarization.
Ans D ST segment is the part of an ECG that reflects the end of the QRS complex to the beginning of the T wave. The part of an ECG that reflects repolarization of the ventricles is the T wave. The part of an ECG used to calculate ventricular rate and rhythm is the RR interval. The part of an ECG that reflects the time from ventricular depolarization through repolarization is the QT interval.
13. A nurse is caring for a patient who is exhibiting ventricular tachycardia (VT). Because the patient is pulseless, the nurse should prepare for what intervention? A) Defibrillation B) ECG monitoring C) Implantation of a cardioverter defibrillator D) Angioplasty
Ans: A Feedback: Any type of VT in a patient who is unconscious and without a pulse is treated in the same manner as ventricular fibrillation: Immediate defibrillation is the action of choice. ECG monitoring is appropriate, but this is an assessment, not an intervention, and will not resolve the problem. An ICD and angioplasty do not address the dysrhythmia.
17. A patient is brought to the ED and determined to be experiencing symptomatic sinus bradycardia. The nurse caring for this patient 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? A) Administer atropine 0.5 mg as an IV bolus every 3 to 5 minutes to a maximum of 3.0 mg. B) Administer atropine as a continuous infusion until symptoms resolve. C) Administer atropine as a continuous infusion to a maximum of 30 mg in 24 hours. D) Administer atropine 1.0 mg sublingually.
Ans: A Feedback: 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.
33. The nurse is caring for a patient who has had a biventricular pacemaker implanted. When planning the patients care, the nurse should recognize what goal of this intervention? A) Resynchronization B) Defibrillation C) Angioplasty D) Ablation
Ans: A Feedback: Biventricular (both ventricles) pacing, also called resynchronization therapy, may be used to treat advanced heart failure that does not respond to medication. This type of pacing therapy is not called defibrillation, angioplasty, or ablation therapy.
1. The nurse is caring for a patient who has had an ECG. The nurse notes that leads I, II, and III differ from one another on the cardiac rhythm strip. How should the nurse best respond? A) Recognize that the view of the electrical current changes in relation to the lead placement. B) Recognize that the electrophysiological conduction of the heart differs with lead placement. C) Inform the technician that the ECG equipment has malfunctioned. D) Inform the physician that the patient is experiencing a new onset of dysrhythmia.
Ans: A Feedback: Each lead offers a different reference point to view the electrical activity of the heart. The lead displays the configuration of electrical activity of the heart. Differences between leads are not necessarily attributable to equipment malfunction or dysrhythmias.
24. A cardiac care nurse is aware of factors that result in positive chronotropy. These factors would affect a patients cardiac function in what way? A) Exacerbating an existing dysrhythmia B) Initiating a new dysrhythmia C) Resolving ventricular tachycardia D) Increasing the heart rate
Ans: D Feedback: Stimulation of the sympathetic system increases heart rate. This phenomenon is known as positive chronotropy. It does not influence dysrhythmias.
19. The nurse is caring for a patient who has just undergone catheter ablation therapy. The nurse in the step- down unit should prioritize what assessment? A) Cardiac monitoring B) Monitoring the implanted device signal C) Pain assessment D) Monitoring the patients level of consciousness (LOC)
Ans: A Feedback: Following catheter ablation therapy, the patient 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.
36).The nurse is caring for a patient who is in the recovery room following the implantation of an ICD. The patient has developed ventricular tachycardia (VT). What should the nurse assess and document? A). ECG to compare time of onset of VT and onset of devices shock B). ECG so physician can see what type of dysrhythmia the patient has C). Patients level of consciousness (LOC) at the time of the dysrhythmia D). Patients activity at time of dysrhythmia
Ans: A Feedback: If the patient has an ICD implanted and develops VT or ventricular fibrillation, the ECG should be recorded to note the time between the onset of the dysrhythmia and the onset of the devices shock or antitachycardia pacing. This is a priority over LOC or activity at the time of onset.
29. A patient is undergoing preoperative teaching before his cardiac surgery and the nurse is aware that a temporary pacemaker will be placed later that day. What is the nurses responsibility in the care of the patients pacemaker? A) Monitoring for pacemaker malfunction or battery failure B) Determining when it is appropriate to remove the pacemaker C) Making necessary changes to the pacemaker settings D) Selecting alternatives to future pacemaker use
Ans: A Feedback: Monitoring for pacemaker malfunctioning and battery failure is a nursing responsibility. The other listed actions are physician responsibilities.
9. A patient who is a candidate for an implantable cardioverter defibrillator (ICD) asks the nurse about the purpose of this device. What would be the nurses best response? A) To detect and treat dysrhythmias such as ventricular fibrillation and ventricular tachycardia B) To detect and treat bradycardia, which is an excessively slow heart rate C) To detect and treat atrial fibrillation, in which your heart beats too quickly and inefficiently D) To shock your heart if you have a heart attack at home
Ans: A Feedback: The ICD is a device that detects and terminates life-threatening episodes of ventricular tachycardia and ventricular fibrillation. It does not treat atrial fibrillation, MI, or bradycardia.
7. A patient the nurse is caring for has a permanent pacemaker implanted with the identification code beginning with VVI. What does this indicate? A) Ventricular paced, ventricular sensed, inhibited B) Variable paced, ventricular sensed, inhibited C) Ventricular sensed, ventricular situated, implanted D) Variable sensed, variable paced, inhibited
Ans: A Feedback: The identification of VVI indicates ventricular paced, ventricular sensed, inhibited.
8. The nurse is caring for an adult patient who has gone into ventricular fibrillation. When assisting with defibrillating the patient, what must the nurse do? A) Maintain firm contact between paddles and patient skin. B) Apply a layer of water as a conducting agent. C) Call all clear once before discharging the defibrillator. D) Ensure the defibrillator is in the sync mode.
Ans: A Feedback: When defibrillating an adult patient, the nurse should maintain good contact between the paddles and the patients skin to prevent arcing, apply an appropriate conducting agent (not water) between the skin and the paddles, and ensure the defibrillator is in the nonsync mode. Clear should be called three times before discharging the paddles.
6. A patient has returned to the cardiac care unit after having a permanent pacemaker implantation. For which potential complication should the nurse most closely assess this patient? A) Chest pain B) Bleeding at the implantation site C) Malignant hyperthermia D) Bradycardia
Ans: B Feedback: 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.
26. A patient is scheduled for catheter ablation therapy. When describing this procedure to the patients family, the nurse should address what aspect of the treatment? A) Resetting of the hearts contractility B) Destruction of specific cardiac cells C) Correction of structural cardiac abnormalities D) Clearance of partially occluded coronary arteries
Ans: B Feedback: Catheter ablation destroys specific cells that are the cause or central conduction route of a tachydysrhythmia. It does not reset the hearts contractility and it does not address structural or vascular abnormalities.
34. When planning the care of a patient with an implanted pacemaker, what assessment should the nurse prioritize? A) Core body temperature B) Heart rate and rhythm C) Blood pressure D) Oxygen saturation level
Ans: B Feedback: For patients with pacemakers, close monitoring of the heart rate and rhythm is a priority, even though each of the other listed vital signs must be assessed.
30. The nurse caring for a patient whose sudden onset of sinus bradycardia is not responding adequately to atropine. What might be the treatment of choice for this patient? A) Implanted pacemaker B) Trancutaneous pacemaker C) ICD D) Asynchronous defibrillator
Ans: B Feedback: If a patient suddenly develops a bradycardia, is symptomatic but has a pulse, and is unresponsive to atropine, emergency pacing may be started with transcutaneous pacing, which most defibrillators are now equipped to perform. An implanted pacemaker is not a time-appropriate option. An asynchronous defibrillator or ICD would not provide relief.
20. The ED nurse is caring for a patient who has gone into cardiac arrest. During external defibrillation, what action should the nurse perform? A) Place gel pads over the apex and posterior chest for better conduction. B) Ensure no one is touching the patient at the time shock is delivered. C) Continue to ventilate the patient via endotracheal tube during the procedure. D) Allow at least 3 minutes between shocks.
Ans: B Feedback: In external defibrillation, both paddles may be placed on the front of the chest, which is the standard paddle placement. Whether using pads, or paddles, the nurse must observe two safety measures. First, maintain good contact between the pads or paddles and the patients skin to prevent leaking. Second, ensure that no one is in contact with the patient or with anything that is touching the patient when the defibrillator is discharged, to minimize the chance that electrical current will be conducted to anyone other than the patient. Ventilation should be stopped during defibrillation.
38. During a CPR class, a participant asks about the difference between cardioversion and defibrillation. What would be the instructors best response? A) Cardioversion is done on a beating heart; defibrillation is not. B) The difference is the timing of the delivery of the electric current. C) Defibrillation is synchronized with the electrical activity of the heart, but cardioversion is not. D) Cardioversion is always attempted before defibrillation because it has fewer risks.
Ans: B Feedback: One major difference between cardioversion and defibrillation is the timing of the delivery of electrical current. In cardioversion, the delivery of the electrical current is synchronized with the patients electrical events; in defibrillation, the delivery of the current is immediate and unsynchronized. Both can be done on beating heart (i.e., in a dysrhythmia). Cardioversion is not necessarily attempted first.
2. The nurse is analyzing a rhythm strip. What component of the ECG corresponds to the resting state of the patients heart? A) P wave B) T wave C) U wave D) QRS complex
Ans: B Feedback: The T wave specifically represents ventricular muscle depolarization, also referred to as the resting state. Ventricular muscle depolarization does not result in the P wave, U wave, or QRS complex.
23. New nurses on the telemetry unit have been paired with preceptors. One new nurse asks her preceptor to explain depolarization. What would be the best answer by the preceptor? A) Depolarization is the mechanical contraction of the heart muscles. B) Depolarization is the electrical stimulation of the heart muscles. C) Depolarization is the electrical relaxation of the heart muscles. D) Depolarization is the mechanical relaxation of the heart muscles.
Ans: B Feedback: The electrical stimulation of the heart is called depolarization, and the mechanical contraction is called systole. Electrical relaxation is called repolarization, and mechanical relaxation is called diastole.
25. The nurse is caring for a patient with refractory atrial fibrillation who underwent the maze procedure several months ago. The nurse reviews the result of the patients most recent cardiac imaging, which notes the presence of scarring on the atria. How should the nurse best respond to this finding? A) Recognize that the procedure was unsuccessful. B) Recognize this as a therapeutic goal of the procedure. C) Liaise with the care team in preparation for repeating the maze procedure. D) Prepare the patient for pacemaker implantation.
Ans: B Feedback: 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.
14. A patient converts from normal sinus rhythm at 80 bpm to atrial fibrillation with a ventricular response at 166 bpm. Blood pressure is 162/74 mm Hg. Respiratory rate is 20 breaths per minute with normal chest expansion and clear lungs bilaterally. IV heparin and Cardizem are given. The nurse caring for the patient understands that the main goal of treatment is what? A) Decrease SA node conduction B) Control ventricular heart rate C) Improve oxygenation D) Maintain anticoagulation
Ans: B Feedback: Treatment for atrial fibrillation is to terminate the rhythm or to control ventricular rate. This is a priority because it directly affects cardiac output. A rapid ventricular response reduces the time for ventricular filling, resulting in a smaller stroke volume. Control of rhythm is the initial treatment of choice, followed by anticoagulation with heparin and then Coumadin.
37).The staff educator is teaching a CPR class. Which of the following aspects of defibrillation should the educator stress to the class? A). Apply the paddles directly to the patients skin. B). Use a conducting medium between the paddles and the skin. C). Always use a petroleum-based gel between the paddles and the skin. D). Any available liquid can be used between the paddles and the skin.
Ans: B Feedback: Use multifunction conductor pads or paddles with a conducting medium between the paddles and the skin (the conducting medium is available as a sheet, gel, or paste). Do not use gels or pastes with poor electrical conductivity.
39. A patient is admitted to the cardiac care unit for an electrophysiology (EP) study. What goal should guide the planning and execution of the patients care? A) Ablate the area causing the dysrhythmia. B) Freeze hypersensitive cells. C) Diagnose the dysrhythmia. D) Determine the nursing plan of care.
Ans: C Feedback: A patient 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 patient be admitted.
11. The nurse is caring for a patient who has just had an implantable cardioverter defibrillator (ICD) placed. What is the priority area for the nurses assessment? A) Assessing the patients activity level B) Facilitating transthoracic echocardiography C) Vigilant monitoring of the patients ECG D) Close monitoring of the patients peripheral perfusion
Ans: C Feedback: After a permanent electronic device (pacemaker or ICD) is inserted, the patients heart rate and rhythm are monitored by ECG. This is a priority over peripheral circulation and activity. Echocardiography is not indicated.
12. During a patients care conference, the team is discussing whether the patient is a candidate for cardiac conduction surgery. What would be the most important criterion for a patient to have this surgery A) Angina pectoris not responsive to other treatments B) Decreased activity tolerance related to decreased cardiac output C) Atrial and ventricular tachycardias not responsive to other treatments D) Ventricular fibrillation not responsive to other treatments
Ans: C Feedback: Cardiac conduction surgery is considered in patients who do not respond to medications and antitachycardia pacing. Angina, reduced activity tolerance, and ventricular fibrillation are not criteria.
5. The nurse is writing a plan of care for a patient with a cardiac dysrhythmia. What would be the most appropriate goal for the patient? A) Maintain a resting heart rate below 70 bpm. B) Maintain adequate control of chest pain. C) Maintain adequate cardiac output. D) Maintain normal cardiac structure.
Ans: C Feedback: For patient safety, the most appropriate goal is to maintain cardiac output to prevent worsening complications as a result of decreased cardiac output. A resting rate of less than 70 bpm is not appropriate for every patient. Chest pain is more closely associated with acute coronary syndrome than with dysrhythmias. Nursing actions cannot normally influence the physical structure of the heart.
16. The nurse is planning discharge teaching for a patient with a newly inserted permanent pacemaker. What is the priority teaching point for this patient? A) Start lifting the arm above the shoulder right away to prevent chest wall adhesion. B) Avoid cooking with a microwave oven. C) Avoid exposure to high-voltage electrical generators. D) Avoid walking through store and library antitheft devices.
Ans: C Feedback: High-output electrical generators can reprogram pacemakers and should be avoided. Recent pacemaker technology allows patients to safely use most household electronic appliances and devices (e.g., microwave ovens). The affected arm should not be raised above the shoulder for 1 week following placement of the pacemaker. Antitheft alarms may be triggered so patients should be taught to walk through them quickly and avoid standing in or near these devices. These alarms generally do not interfere with pacemaker function.
4. An adult patient with third-degree AV block is admitted to the cardiac care unit and placed on continuous cardiac monitoring. What rhythm characteristic will the ECG most likely show? A) PP interval and RR interval are irregular. B) PP interval is equal to RR interval. C) Fewer QRS complexes than P waves D) PR interval is constant.
Ans: C Feedback: In third-degree AV block, no atrial impulse is conducted through the AV node into the ventricles. As a result, there are impulses stimulating the atria and impulses stimulating the ventricles. Therefore, there are more P waves than QRS complexes due to the difference in the natural pacemaker (nodes) rates of the heart. The other listed ECG changes are not consistent with this diagnosis.
27. A patient has undergone diagnostic testing and received a diagnosis of sinus bradycardia attributable to sinus node dysfunction. When planning this patients care, what nursing diagnosis is most appropriate? A) Acute pain B) Risk for unilateral neglect C) Risk for activity intolerance D) Risk for fluid volume excess
Ans: C Feedback: 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.
3. The nursing educator is presenting a case study of an adult patient who has abnormal ventricular depolarization. This pathologic change would be most evident in what component of the ECG? A) P wave B) T wave C) QRS complex D) U wave
Ans: C Feedback: The QRS complex represents the depolarization of the ventricles and, as such, the electrical activity of that ventricle.
31. The nurse is caring for a patient who has had a dysrhythmic event. The nurse is aware of the need to assess for signs of diminished cardiac output (CO). What change in status may signal to the nurse a decrease in cardiac output? A) Increased blood pressure B) Bounding peripheral pulses C) Changes in level of consciousness D) Skin flushing
Ans: C Feedback: The nurse conducts a physical assessment to confirm the data obtained from the history and to observe for signs of diminished cardiac output (CO) during the dysrhythmic event, especially changes in level of consciousness. Blood pressure tends to decrease with lowered CO and bounding peripheral pulses are inconsistent with this problem. Pallor, not skin flushing, is expected.
18. An ECG has been ordered for a newly admitted patient. What should the nurse do prior to electrode placement? A) Clean the skin with providone-iodine solution. B) Ensure that the area for electrode placement is dry. C) Apply tincture of benzoin to the electrode sites and wait for it to become tacky. D) Gently abrade the skin by rubbing the electrode sites with dry gauze or cloth.
Ans: D Feedback: An ECG is obtained by slightly abrading the skin with a clean dry gauze pad and placing electrodes on the body at specific areas. The abrading of skin will enhance signal transmission. Disinfecting the skin is unnecessary and conduction gel is used.
10. A nurse is providing health education to a patient scheduled for cryoablation therapy. The nurse should describe what aspect of this treatment? A) Peeling away the area of endocardium responsible for the dysrhythmia B) Using electrical shocks directly to the endocarduim to eliminate the source of dysrhythmia C) Using high-frequency sound waves to eliminate the source of dysrhythmia D) Using a cooled probe to eliminate the source of dysrhythmia
Ans: D Feedback: Cryoablation therapy involves using a cooled probe to create a small scar on the endocardium to eliminate the source of the dysrhythmias. Endocardium resection involves peeling away a specified area of the endocardium. Electrical ablation involves using shocks to eliminate the area causing the dysrhythmias. Radio frequency ablation uses high-frequency sound waves to destroy the area causing the dysrhythmia
28. The nurse is caring for a patient on telemetry. The patients ECG shows a shortened PR interval, slurring of the initial QRS deflection, and prolonged QRS duration. What does this ECG show? A) Sinus bradycardia B) Myocardial infarction C) Lupus-like syndrome D) Wolf-Parkinson-White (WPW) syndrome
Ans: D Feedback: In WPW syndrome there is a shortened PR interval, slurring (called a delta wave) of the initial QRS deflection, and prolonged QRS duration. These characteristics are not typical of the other listed cardiac anomalies.
40. A patient calls his cardiologists office and talks to the nurse. He is concerned because he feels he is being defibrillated too often. The nurse tells the patient to come to the office to be evaluated because the nurse knows that the most frequent complication of ICD therapy is what? A) Infection B) Failure to capture C) Premature battery depletion D) Oversensing of dysrhythmias
Ans: D Feedback: Inappropriate delivery of ICD therapy, usually due to oversensing of atrial and sinus tachycardias with a rapid ventricular rate response, is the most frequent complication of ICD. Infections, failure to capture, and premature battery failure are less common.
22. The nurse is providing care to a patient who has just undergone an electrophysiologic (EP) study. The patient states that she is nervous about things going wrong during the procedure. What is the nurses best response? A) This is basically a risk-free procedure. B) Thousands of patients undergo EP every year. C) Remember that this is a step that will bring you closer to enjoying good health. D) The whole team will be monitoring you very closely for the entire procedure.
Ans: D Feedback: Patients who are to undergo an EP study may be anxious about the procedure and its outcome. A detailed discussion involving the patient, the family, and the electrophysiologist usually occurs to ensure that the patient can give informed consent and to reduce the patients anxiety about the procedure. It is inaccurate to state that EP is risk-free and stating that it is common does not necessarily relieve the patients anxiety. Characterizing EP as a step toward good health does not directly address the patients anxiety
32. Following cardiac resuscitation, a patient has been placed in a state of mild hypothermia before being transferred to the cardiac intensive care unit. The nurses assessment reveals that the patient is experiencing neuromuscular paralysis. How should the nurse best respond? A) Administer hypertonic IV solution. B) Administer a bolus of warned normal saline. C) Reassess the patient in 15 minutes. D) Document this as an expected assessment finding.
Ans: D Feedback: The nurse caring for a patient with hypothermia (passive or induced) needs to monitor for appropriate level of cooling, sedation, and neuromuscular paralysis to prevent seizures; myoclonus; and shivering. Neuromuscular paralysis is an expected finding and does not necessitate further interventions.
Ectopic rhythms
Atrial rhythms and all other rhythms that originate in a pacemaker other than the sinus node.
Conduction abnormalities
Atrioventricular blocks (AV) occur when conduction of the impulse through the AV node or bundle of his is decreased or stopped Can be caused by medications, MI, cardiomyopathy AV block may be temporary or resolve on its own Permanent pacemaker may be needed
What are dysrhythmias?
Disorders of formation or conduction (or both) of electrical impulses within heart Can cause disturbances of -Rate -Rhythm -Both rate and rhythm -Potentially can alter blood flow and cause hemodynamic changes -Diagnosed by analysis of electrographic waveform
Cardioversion vs Defibrillation
Electrical cardioversion involves the delivery of a "timed" electrical current to end a tachy-dysrhythmia. (Elective and not an emergency) The defibrillator is set to synchronize with ECG so that the impulse discharges during ventricular depolarization Medicate patient per MD order and follow hospital's moderate sedation protocol Defibrillation is an asynchronous shock and is an EMERGENCY
What is a Pacemakers?
Electronic device that provides electrical stimuli to heart muscle Types - Permanent - Temporary: used only in hospital settings Permanent pacemaker - Consists of an electronic pulse generator and pacemaker electrodes - Generator contains circuitry and batteries that determine the rate and strength (output). Usually last for 10 years Capture: depolarization of intended chamber (QRS complex)
Most common cause's of PVC's
Etiology of PVCs: - Increased catecholamine and sympathetic tone - Stimulants: caffeine, alcohol, tobaccoCardiac ischemia or infarction - Increased workload on the heart (tachycardia, heart failure) - Digitalis toxicity, hypoxia, acidosis, electrolyte imbalance (hypokalemia)
Regularity-Based Heart Rate Calculation
Heart rate calculation is regularity based. Rhythm regularity is concerned with the spacing of the QRS complexes. Compare the R-R intervals. - Count the number of little blocks between QRS complexes. - Go from spike to spike. Regular rhythm - Regular R-R intervals vary by only 1 or 2 little blocks. - QRS complexes usually look alike.
Atrial Fibrillation (looks like saw tooth but QRS NOT in sync)
Most common sustained dysrhythmia Results from abnormal impulse formation that occurs when structural or electrophysiological abnormalities alter the atrial tissue causing rapid, disorganized and uncoordinated twitching of the atrial musculature Atrial rate is 300-600 bpm; ventricular rate is usually 120-200 bpm in untreated (uncontrolled) Irregularly irregular
Sinus rhythm
Normal heart rhythm
Atrial Dysrhythmias Atrial Flutter (saw tooth prior to QRS but all coordinated)
Occurs because of a conduction defect in the atrium that causes a rapid, regular atrial impulse at a rate 250-400 bpm. Atrial rate is regular and the ventricle rate regular but slower 70-150 as the AV node cannot conduct that fast and causes a therapeutic block
Sinus Tachycardia
Occurs when the sinus node creates an impulse faster than normal. - Causes include physiological or psychological stress, ie: blood loss, hypovolemia, heart failure pain, fever, exercise, shock, anxiety - Medications that stimulate sympathetic response (atropine), stimulants (caffeine, nicotine) and illicit drugs (amphetamines, cocaine)
Components of the Electrocardiogram What does the each wave represent on an ECG?
P wave - Represents the electrical impulse starting in the SA node and spreading through the Atria. Atrial depolarization QRS - represents ventricular depolarization Not all QRS complexes have all three waveforms Q wave is the first negative deflection after P wave R wave is the first positive deflection after P wave S wave is the first negative deflection after R waveT wave represents ventricular repolarization
Nursing Process: Care of the Patient with a Dysrhythmia—Assessment #2
Physical assessment include - Skin (pale and cool) - Signs of fluid retention (JVD, lung auscultation) - Rate, rhythm of apical, peripheral pulsesHeart sounds Blood pressure, pulse pressure
What after care is needed for a Permanent Pacemaker insertion?
Pt. must rest x 24 hours to ensure lead fixation •Monitor for dysrhythmias, sensing, capturing •Incisional care •Afebrile
Degrees of Heart Blocks Second Degree Atrioventricular Block, Type 1 (Wenckebach)
Repeating pattern in which all but one of a series of atrial impulses are conducted through the AV node into ventricles. Each atrial impulse takes a longer time for conduction than the one before, until one is completely blocked.
Atrial Fibrillation medical management
Synchronized cardioversion - For unstable patients - TEE performed prior to rule out clots in left atrium -Anticoagulate for period of time before cardioversion Catheter Ablation therapy - Destroys specific cells that are causing the dysrhythmia "Maze" procedure for persons undergoing heart surgery - Small transmural incision made through the Atria, scar tissue Left Atrial appendage Occlusion (LAAO) - A device is threaded through the opening of the LAA sealing it off
Ventricular Tachycardia (VT) (complete saw blade look)
•Multiple PVC's (in a row) •Ventricular rate between 140-250 beats/minCauses• Heart disease, electrolyte imbalance, hypoxia, side effect of drugs Treatment - Amiodarone ***- Cardioversion if unstable WITH pulse, defibrillation if pulseless Treat the cause. - Supplemental potassium, oxygen. Automated implantable cardioverter-defibrillator (AICD) or catheter ablation - If pulse-less CPR and Advanced Cardiac Life Support (ACLS)
