Gyan Darpan : Learning Portal

Dysrhythmias & EKG Interpretation Q 1

noreply@blogger.com (Surendra Tetarwal) — Fri, 29 Apr 2022 06:45:00 +0530

A nurse is assessing an electrocardiogram rhythm strip. The P waves and QRS complexes are regular. The PR interval is 0.16 second, and QRS complexes measure 0.06 second. The overall heart rate is 64 beats per minute. The nurse assesses the cardiac rhythm as:

A. Normal sinus rhythm

B. Sinus bradycardia

C. Sick sinus syndrome

D. First-degree heart block

Correct Answer: A. Normal sinus rhythm

Measurements are normal, measuring 0.12 to 0.20 second and 0.4 to 0.10 second, respectively. Sinus rhythms originate in the SA node. The SA node is located in the right atrium and is the heart’s natural pacemaker. The normal rate of the SA node is between 60 and 100. On ECG, sinus rhythm is represented by monomorphic P waves before each QRS complex and is regular.

Option B: Sinus bradycardia is a cardiac rhythm with appropriate cardiac muscle depolarization initiating from the sinus node generating less than 60 beats per minute (bpm). The diagnosis of sinus bradycardia requires visualization of an electrocardiogram showing a normal sinus rhythm at a rate lower than 60 bpm.

Option C: Sick sinus syndrome, also known as sinus node dysfunction (SND), is a disorder of the sinoatrial (SA) node caused by impaired pacemaker function and impulse transmission producing a constellation of abnormal rhythms. These include atrial bradyarrhythmias, atrial tachyarrhythmias and, sometimes, bradycardia alternates with tachycardia often referred to as “tachy-brady syndrome.”

Option D: First-degree atrioventricular (AV) block is a condition of abnormally slow conduction through the AV node. It is defined by ECG changes that include a PR interval of greater than 0.20 without disruption of atrial to ventricular conduction.

Dysrhythmias & EKG Interpretation Q 2

noreply@blogger.com (Surendra Tetarwal) — Fri, 29 Apr 2022 06:15:00 +0530

A nurse notes that a client with sinus rhythm has a premature ventricular contraction that falls on the T wave of the preceding beat. The client’s rhythm suddenly changes to one with no P waves or definable QRS complexes. Instead, there are coarse wavy lines of varying amplitude. The nurse assesses this rhythm to be:

A. Ventricular tachycardia

B. Ventricular fibrillation

C. Atrial fibrillation

D. Asystole

Correct Answer: B. Ventricular fibrillation

Ventricular fibrillation is characterized by irregular, chaotic undulations of varying amplitudes. Ventricular fibrillation has no measurable rate and no visible P waves or QRS complexes and results from electrical chaos in the ventricles. VF is a WCT caused by irregular electrical activity and characterized by a ventricular rate of usually greater than 300 with discrete QRS complexes on the electrocardiogram (ECG). QRS morphology in VF varies in shape, amplitude, and duration with a prominent irregular rhythm.

Option A: Ventricular tachycardia is characterized by the absence of P waves, wide QRS complexes (usually greater than 0.14 second), and a rate between 100 and 250 impulses per minute. The rhythm is usually regular. Ventricular tachycardia is characterized as a wide complex (QRS duration greater than 120 milliseconds) tachyarrhythmia at a heart rate greater than 100 beats per minute. It is classified by duration as non-sustained or sustained. Non-sustained ventricular tachycardia is defined as more than 3 beats of ventricular origin at a rate greater than 100 beats per minute that lasts less than 30 seconds in duration.

Option C: Atrial fibrillation is characterized by a loss of P waves; an undulating, wavy baseline; QRS duration that is often within normal limits; and an irregular ventricular rate, which can range from 60 to 100 beats per minute (when controlled with medications) to 100 to 160 beats per minute (when uncontrolled). Atrial fibrillation is the most common type of cardiac arrhythmia. It is the leading cardiac cause of stroke. Risk factors for atrial fibrillation include advanced age, high blood pressure, underlying heart and lung disease, congenital heart disease, and increased alcohol consumption.

Option D: Asystole, colloquially referred to as flatline, represents the cessation of electrical and mechanical activity of the heart. Asystole typically occurs as a deterioration of the initial non-perfusing ventricular rhythms: ventricular fibrillation (V-fib) or pulseless ventricular tachycardia (V-tach). Additionally, pulseless electrical activity (PEA) can cease and become asystole.

Dysrhythmias & EKG Interpretation Q 3

noreply@blogger.com (Surendra Tetarwal) — Fri, 29 Apr 2022 05:45:00 +0530

While caring for a client who has sustained an MI, the nurse notes eight PVCs in one minute on the cardiac monitor. The client is receiving an IV infusion of D5W and oxygen at 2 L/minute. The nurse’s first course of action should be to:

A. Increase the IV infusion rate.

B. Notify the physician promptly.

C. Increase the oxygen concentration.

D. Administer a prescribed analgesic.

Correct Answer: B. Notify the physician promptly.

PVCs are often a precursor of life-threatening dysrhythmias, including ventricular tachycardia and ventricular fibrillation. An occasional PVC is not considered dangerous, but if PVCs occur at a rate greater than 5 or 6 per minute in the post-MI client, the physician should be notified immediately. More than 6 PVCs per minute is considered serious and usually calls for decreasing ventricular irritability by administering medications such as lidocaine.

Option A: Increasing the IV infusion rate would not decrease the number of PVCs. Those experiencing frequent PVCs or symptomatic PVCs should be evaluated to identify the etiology. In many cases, excess intake of stimulants and/or lower levels of potassium and magnesium is the cause of the PVCs. These patients can be easily managed via minimization of stimulants and/or repletion of electrolytes.

Option C: Increasing the oxygen concentration should not be the nurse’s first course of action; rather, the nurse should notify the physician promptly. In the emergency room, hypoxic patients need to be provided with oxygen, the electrolyte imbalance should be corrected and drug toxicity should be ruled out. At the same time, an acute MI must be ruled out.

Option D: Administering a prescribed analgesic would not decrease ventricular irritability. The medication classes used to treat frequent and/or symptomatic PVCs include antiarrhythmics, beta-blockers, and calcium channel blockers. Commonly used antiarrhythmics include amiodarone and flecainide.

Dysrhythmias & EKG Interpretation Q 4

noreply@blogger.com (Surendra Tetarwal) — Fri, 29 Apr 2022 05:15:00 +0530

The adaptations of a client with complete heart block would most likely include:

A. Nausea and vertigo

B. Flushing and slurred speech

C. Cephalalgia and blurred vision

D. Syncope and slow ventricular rate

Correct Answer: D. Syncope and slow ventricular rate

In complete atrioventricular block, the ventricles take over the pacemaker function in the heart but at a much slower rate than that of the SA node. As a result, there is decreased cerebral circulation, causing syncope. Patients with third-degree blocks can have varying clinical presentations. Rarely, patients are asymptomatic. Usually, they may present with generalized fatigue, tiredness, chest pain, shortness of breath, presyncope, or syncope. They may have significant hemodynamic instability and can be obtunded.

Option A: The physical exam is usually remarkable for bradycardia. JVP examination often demonstrates cannon A-waves owing to the simultaneous contraction of the atria and ventricles. Thus a very large pressure wave is felt up against the vein.

Option B: Especially with heart rates below 40/min, patients might also present with features consistent with decompensated heart failure, respiratory distress, and hypoperfusion such as diaphoresis, tachypnea, altered mental status, retraction, cool skin, and decreased capillary refill.

Option C: Patients with complete AV-block accompanying an acute myocardial infarction often have ischemic symptoms of chest pain or dyspnea. The past medical history will often include the presence of cardiovascular disease and/or its risk factors, including diabetes mellitus, hypertension, dyslipidemia, and smoking, etc.

Dysrhythmias & EKG Interpretation Q 5

noreply@blogger.com (Surendra Tetarwal) — Fri, 29 Apr 2022 04:45:00 +0530

A client with a bundle branch block is on a cardiac monitor. The nurse should expect to observe:

A. Sagging ST segments.

B. Absence of P wave configurations.

C. Inverted T waves following each QRS complex.

D. Widening of QRS complexes to 0.12 second or greater.

Correct Answer: D. Widening of QRS complexes to 0.12 second or greater.

Bundle branch block interferes with the conduction of impulses from the AV node to the ventricle supplied by the affected bundle. Conduction through the ventricles is delayed, as evidenced by a widened QRS complex. Rhythm must be of supraventricular origin (EG: ventricular activation coming from atrial or AV nodal activation). Lead V1 should have either a QS or a small r wave with large S wave. Lead V6 should have a notched R wave and no Q wave.

Option A: ST depression occurs when the J point is displaced below baseline. Just like ST elevation, not all ST depression represents myocardial ischemia or an emergent condition. There are multiple conditions associated with ST depression. Some of these include hypokalemia, cardiac ischemia, and medications such as digitalis.

Option B: Absence of P waves suggests either no normal atrial depolarization, e.g., atrial fibrillation, atrial standstill; or the P waves are hidden within the QRS complexes, e.g., ventricular tachycardia, junctional tachycardia.

Option C: Inverted T waves are associated with myocardial ischemia. The inversion of a T wave is not specific for ischemia, and the inversion itself does not correlate with a specific prognosis. However, if the clinical history is suggestive of ischemia in the setting of inverted T waves, this is correlative.

Dysrhythmias & EKG Interpretation Q 6

noreply@blogger.com (Surendra Tetarwal) — Fri, 29 Apr 2022 04:15:00 +0530

When ventricular fibrillation occurs in a CCU, the first person reaching the client should:

A. Administer oxygen.

B. Defibrillate the client.

C. Initiate CPR.

D. Administer sodium bicarbonate intravenously.

Correct Answer: B. Defibrillate the client

Ventricular fibrillation is a death-producing dysrhythmia and, once identified, must be terminated immediately by precordial shock (defibrillation). This is usually a standing physician’s order in a CCU. Pulseless VT and VF are both shockable rhythms, and once the staff identifies the rhythm as VF, patients should be shocked immediately with 120 to 200 joules on a biphasic defibrillator or 360 joules using a monophasic.

Option A: Professionals should undertake cause-specific measures such as securing the airway, correcting electrolytes, administering fluids, decompressing pneumothorax, draining tamponade while resuscitating the patient. Once the patient attains return of spontaneous circulation (ROSC), physicians should begin a definitive evaluation for coronary artery disease.

Option C: Due to the high mortality rate and extreme acuity of the condition, VF patients warrant immediate attention. Healthcare professionals should immediately initiate guideline-directed management as per Advanced Cardiac Life Support (ACLS) protocol. There is a lower likelihood of survival if the healthcare professional deviates from the ACLS guidelines. All patients with cardiac arrest should have an initial assessment while receiving quality CPR.

Option D: Administer epinephrine and amiodarone as per ACLS protocol in patients sustaining VF rhythm regardless of receiving 3 shocks. Amiodarone significantly improves survival to hospital admission without affecting survival to hospital discharge.

Dysrhythmias & EKG Interpretation Q 7

noreply@blogger.com (Surendra Tetarwal) — Fri, 29 Apr 2022 03:45:00 +0530

What criteria should the nurse use to determine normal sinus rhythm for a client on a cardiac monitor? Select all that apply.

A. The RR intervals are relatively consistent.

B. One P wave precedes each QRS complex.

C. Four to eight complexes occur in a 6-second strip.

D. The ST segment is higher than the PR interval.

E. The QRS complex ranges from 0.12 to 0.20 second.

Correct Answers: A, B.

The consistency of the RR interval indicates regular rhythm. A normal P wave before each complex indicates the impulse originated in the SA node. Sinus arrhythmia is most typically present in young, healthy individuals. Studies have attempted to establish an increased prevalence in patients with underlying hypertension, obesity, and diabetes.

Option A: Sinus rhythm (a.k.a. normal sinus rhythm) refers to the normal heart beat originating from the sinoatrial node. This is manifested as an upright P wave in lead II of the ECG. Sinus arrhythmia is a common rhythm variation. It is seen more often in children and young adults. Respirations lead to vagal stimuli resulting in R-R interval variations.

Option B: Sinus arrhythmia is a commonly encountered variation of normal sinus rhythm. Sinus arrhythmia characteristically presents with an irregular rate in which the variation in the R-R interval is greater than 0.12 seconds. Additionally, P waves are typically monoform and in a pattern consistent with atrial activation originating from the sinus node.

Option C: The number of complexes in a 6-second strip is multiplied by 10 to approximate the heart rate; normal sinus rhythm is 60 to 100. On the EKG, sinus rhythm appears as a beat-to-beat variation in the P-P interval. Typically, this variation is greater than 120 msec: the P-P interval increases and decreases with inspiration and exhalation.

Option D: Elevation of the ST segment is a sign of cardiac ischemia and is unrelated to the rhythm. The ST Segment represents the interval between ventricular depolarization and repolarization. The most important cause of ST segment abnormality (elevation or depression) is myocardial ischaemia or infarction.

Option E: The QRS duration should be less than 0.12 second; the PR interval should be 0.12 to 0.20 second. The normal duration (interval) of the QRS complex is between 0.08 and 0.10 seconds — that is, 80 and 100 milliseconds. When the duration is between 0.10 and 0.12 seconds, it is intermediate or slightly prolonged. A QRS duration of greater than 0.12 seconds is considered abnormal.

Dysrhythmias & EKG Interpretation Q 8

noreply@blogger.com (Surendra Tetarwal) — Fri, 29 Apr 2022 03:15:00 +0530

When auscultating the apical pulse of a client who has atrial fibrillation, the nurse would expect to hear a rhythm that is characterized by:

A. The presence of occasional coupled beats.

B. Long pauses in an otherwise regular rhythm.

C. A continuous and totally unpredictable irregularity.

D. Slow but strong and regular beats.

Correct Answer: C. A continuous and totally unpredictable irregularity.

In atrial fibrillation, multiple ectopic foci stimulate the atria to contract. The AV node is unable to transmit all of these impulses to the ventricles, resulting in a pattern of highly irregular ventricular contractions. Due to its rhythm irregularity, blood flow through the heart becomes turbulent and has a high chance of forming a thrombus (blood clot), which can ultimately dislodge and cause a stroke. Atrial fibrillation is the leading cardiac cause of stroke.

Option A: The most common sensation associated with PVCs is that of a skipped heartbeat followed by a fluttering sensation. Patients commonly present complaining of heart palpitations. The vast majority of patients are entirely asymptomatic as there are no associated symptoms with the palpitations.

Option B: In the presence of a pause, one should exclude premature complexes with compensatory pause. If the ectopic beat failed to reset the sinus node, the premature complex would be followed by a compensatory pause, i.e. the R-R interval after the premature complex is longer than the R-R interval between normal sinus beats.

Option D: Having bradycardia means that the heart beats very slowly. For most people, a heart rate of 60 to 100 beats a minute while at rest is considered normal. If the heart beats less than 60 times a minute, it is slower than normal. For some people, a slow heart rate does not cause any problems. It can be a sign of being very fit. Healthy young adults and athletes often have heart rates of less than 60 beats a minute.

Dysrhythmias & EKG Interpretation Q 9

noreply@blogger.com (Surendra Tetarwal) — Fri, 29 Apr 2022 02:45:00 +0530

Atherosclerosis impedes coronary blood flow by which of the following mechanisms?

A. Plaques obstruct the vein.

B. Plaques obstruct the artery.

C. Blood clots form outside the vessel wall.

D. Hardened vessels dilate to allow blood to flow through.

Correct Answer: B. Plaques obstruct the artery

Atherosclerosis is a chronic inflammatory disease in which there is a build up of plaques inside arteries. These plaques are principally composed of lipids that induce an inflammatory reaction causing turbulent flow with atherosclerotic cardiovascular disease (ASCVD) as a result.

Option A: Arteries, not veins, supply the coronary arteries with oxygen and other nutrients. Atherosclerosis mainly develops through the continuous process of arterial wall lesions due to lipid retention by trapping in the intima by a matrix such as proteoglycans resulting in a modification which, in turn, aggravates chronic inflammation at vulnerable sites in the arteries and plays an important role at all phases of the atherogenic progression.

Option C: Atherosclerosis is a direct result of plaque formation in the artery. This process begins from the nascent fatty streaks in the arterial intima which evolve into fibrous plaques and emerge into complex atherosclerotic lesions that are susceptible to rupture. Also, stenosis from the inward expansion of the atheroma can result in occlusion of vessels such as the coronaries.

Option D: Hardened vessels can’t dilate properly and, therefore, constrict blood flow. Many studies indicate the role of the endoplasmic reticulum stress pathway or unfolded protein response as the chief mechanisms of macrophage cell death in plaques causing accumulation of dead macrophages. Also in comparison to early plaques, microvessel density is increased in advanced plaques by dysregulated neovascularization. In normal and atherosclerotic arteries microvessels are thin-walled and characterized with poor structural integrity and endothelial junctions.

Dysrhythmias & EKG Interpretation Q 10

noreply@blogger.com (Surendra Tetarwal) — Fri, 29 Apr 2022 02:15:00 +0530

A paradoxical pulse occurs in a client who had a coronary artery bypass graft (CABG) surgery two (2) days ago. Which of the following surgical complications should the nurse suspect?

A. Left-sided heart failure

B. Aortic regurgitation

C. Complete heart block

D. Pericardial tamponade

Correct Answer: D. Pericardial tamponade

A paradoxical pulse (a palpable decrease in pulse amplitude on quiet inspiration) signals pericardial tamponade, a complication of CABG surgery. Cardiac tamponade is a medical or traumatic emergency that happens when enough fluid accumulates in the pericardial sac compressing the heart and leading to a decrease in cardiac output and shock.

Option A: Left-sided heart failure can cause pulsus alternans (pulse amplitude alternation from beat to beat, with a regular rhythm). Right ventricular alternans occur as a result of right ventricular strain, often precipitated by a pulmonary embolism or pulmonary hypertension. Other potential etiologies of right ventricular alternans include reactive airway disease, mitral stenosis, or left-sided heart failure.

Option B: Aortic regurgitation may cause bisferious pulse (an increased arterial pulse with a double systolic peak). The most common causes of pulsus bisferiens are mixed aortic valve disease (infective endocarditis, rheumatic heart disease, Marfan syndrome, bicuspid aortic valve) and hypertrophic cardiomyopathy with obstruction (HOCM). Pulsus bisferiens a single central pulse wave with two peaks separated by a distinct mid-systolic dip. An early component percussion wave results from rapid left ventricular ejection. The late component tidal wave represents a reflected wave from the periphery due to an artery’s recoil effect.

Option C: Complete heart block may cause a bounding pulse (a strong pulse with increased pulse pressure). The physical exam is usually remarkable for bradycardia. JVP examination often demonstrates cannon A-waves owing to the simultaneous contraction of the atria and ventricles. Thus a very large pressure wave is felt up against the vein.

Dysrhythmias & EKG Interpretation Q 11

noreply@blogger.com (Surendra Tetarwal) — Fri, 29 Apr 2022 01:45:00 +0530

A nurse notices frequent artifacts on the ECG monitor for a client whose leads are connected by cable to a console at the bedside. The nurse examines the client to determine the cause. Which of the following items is unlikely to be responsible for the artifact?

A. Frequent movement of the client.

B. Tightly secured cable connections.

C. Leads applied over hairy areas.

D. Leads applied to the limbs.

Correct Answer: B. Tightly secured cable connections.

Motion artifact, or “noise,” can be caused by frequent client movement, electrode placement on limbs, and insufficient adhesion to the skin, such as placing electrodes over hairy areas of the skin. Electrode placement over bony prominences also should be avoided. Signal interference can also occur with electrode removal and cable disconnection. The artifacts produced by alternating current cause a “darkened reinforcement” in the ECG baseline, often making an analysis of rhythm difficult. This is due to lack of filters for alternating current systems or a poor operation of the device.

Option A: In Parkinson’s disease and parkinsonian syndromes, continuous muscle twitching can be mistaken for atrial flutter (pseudo?atrial flutter) due to gross and constant irregularities with a 300 bpm rate. In such cases, electrodes should be placed at the upper part of the arms and legs. To eliminate limb tremors due to Parkinson’s disease, the electrodes should be placed at the roots of the limbs, which attenuates or abolishes the tremors and the myopotentials.

Option C: Incorrect connections of electrodes during ECG recordings may resemble rhythm or conduction alterations, myocardial ischemia or infarction. They also cause shifts in P waves and the QRS axis, and they may mimic ectopic atrial rhythms, fascicular block or dextrocardia; the latter occurring with left arm?right arm reversal.

Option D: A frequent mistake when performing an ECG is a positioning of the right precordial leads (V1, V2, V3); too high or too low, i.e., above the 4th intercostal space observed in 50% of tracings or inferior and left shift in 30%–50% of the cases in leads V4 through V6, which indicates that these lateral precordial leads are commonly placed outside their respective anatomical sites.

Dysrhythmias & EKG Interpretation Q 12

noreply@blogger.com (Surendra Tetarwal) — Fri, 29 Apr 2022 01:15:00 +0530

A woman with severe mitral stenosis and mitral regurgitation has a pulmonary artery catheter inserted. The physician orders pulmonary artery pressure monitoring, including pulmonary capillary wedge pressures. The purpose of this is to help assess the:

A. Degree of coronary artery stenosis.

B. Peripheral arterial pressure.

C. Pressure from fluid within the left ventricle.

D. Oxygen and carbon dioxide concentration is the blood.

Correct Answer: C. Pressure from fluid within the left ventricle.

The pulmonary artery pressures are used to assess the heart’s ability to receive and pump blood. The pulmonary capillary wedge pressure reflects the left ventricle end-diastolic pressure and guides the physician in determining fluid management for the client. Pulmonary capillary wedge pressure (PCWP) is frequently used to assess left ventricular filling, represent left atrial pressure, and assess mitral valve function. It is measured by inserting a balloon-tipped, multi-lumen catheter (Swan-Ganz catheter) into a central vein, and advancing the catheter into a branch of the pulmonary artery.

Option A: The degree of coronary artery stenosis is assessed during a cardiac catheterization. Although it is used for cardiac hemodynamics and assessment of valvular lesions, its main diagnostic role is the assessment of coronary artery disease. In the contemporary era, left heart catheterization, especially selective coronary angiogram, is considered the gold standard test for coronary artery disease diagnosis.

Option B: The peripheral arterial pressure is assessed with an arterial line. Arterial pressure directly corresponds to cardiac output, arterial elasticity, and peripheral vascular resistance. Blood pressure is remarkably easy to alter and can be affected by many activities. In response to acute changes in blood pressure, the body responds through the baroreceptors located within blood vessels. Baroreceptors are a form of mechanoreceptor that becomes activated by the stretching of the vessel. This sensory information is conveyed to the central nervous system and used to influence peripheral vascular resistance and cardiac output.

Option D: An arterial blood gases (ABG) test measures the acidity (pH) and the levels of oxygen and carbon dioxide in the blood from an artery. This test is used to find out how well the lungs are able to move oxygen into the blood and remove carbon dioxide from the blood. As blood passes through the lungs, oxygen moves into the blood while carbon dioxide moves out of the blood into the lungs. An ABG test uses blood drawn from an artery, where the oxygen and carbon dioxide levels can be measured before they enter body tissues.

Dysrhythmias & EKG Interpretation Q 13

noreply@blogger.com (Surendra Tetarwal) — Fri, 29 Apr 2022 00:45:00 +0530

A nurse is watching the cardiac monitor and notices that the rhythm suddenly changes. There are no P waves, the QRS complexes are wide, and the ventricular rate is regular but over 100. The nurse determines that the client is experiencing:

A. Premature ventricular contractions

B. Ventricular tachycardia

C. Ventricular fibrillation

D. Sinus tachycardia

Correct Answer: B. Ventricular tachycardia

Ventricular tachycardia is characterized by the absence of P waves, wide QRS complexes (usually greater than 0.14 second), and a rate between 100 and 250 impulses per minute. The rhythm is usually regular. Ventricular tachycardia is characterized as a wide complex (QRS duration greater than 120 milliseconds) tachyarrhythmia at a heart rate greater than 100 beats per minute. It is classified by duration as non-sustained or sustained. Non-sustained ventricular tachycardia is defined as more than 3 beats of ventricular origin at a rate greater than 100 beats per minute that lasts less than 30 seconds in duration.

Option A: During a premature ventricular contraction (PVC), the heartbeat is initiated by the Purkinje fibers rather than the SA node. Given that a PVC occurs before a regular heartbeat, there is a pause before the next regular heartbeat. In patients with PVCs, the ECG may reveal other findings that include: electrolyte abnormalities (peaked T waves, QT prolongation); left ventricular hypertrophy; with an old MI, one may see Q waves, loss of R waves, and/or a bundle branch block; and acute ischemia may present with ST-segment elevation/depression and/or T wave inversion.

Option C: VF is a WCT caused by irregular electrical activity and characterized by a ventricular rate of usually greater than 300 with discrete QRS complexes on the electrocardiogram (ECG). QRS morphology in VF varies in shape, amplitude, and duration with a prominent irregular rhythm.

Option D: Sinus tachycardia is a regular cardiac rhythm in which the heart beats faster than normal and results in an increase in cardiac output. While it is common to have sinus tachycardia as a compensatory response to exercise or stress, it becomes concerning when it occurs at rest.

Dysrhythmias & EKG Interpretation Q 14

noreply@blogger.com (Surendra Tetarwal) — Fri, 29 Apr 2022 00:15:00 +0530

A nurse is viewing the cardiac monitor in a client’s room and notes that the client has just gone into ventricular tachycardia. The client is awake and alert and has good skin color. The nurse would prepare to do which of the following?

A. Immediately defibrillate.

B. Prepare for pacemaker insertion.

C. Administer amiodarone (Cordarone) intravenously.

D. Administer epinephrine (Adrenaline) intravenously.

Correct Answer: C. Administer amiodarone (Cordarone) intravenously.

First-line treatment of ventricular tachycardia in a client who is hemodynamically stable is the use of antidysrhythmics such as amiodarone (Cordarone), lidocaine (Xylocaine), and procainamide (Pronestyl). Cardioversion also may be needed to correct the rhythm (cardioversion is recommended for stable ventricular tachycardia). Procainamide will terminate between 50% and 80% of ventricular tachycardias, and it will slow the conduction of those that it does not terminate. Amiodarone will convert about 30% of patients to sinus rhythm but is very effective in reducing the reversion rate of refractory SMVT.

Option A: Defibrillation is used with pulseless ventricular tachycardia. Pulseless VT requires immediate electrical cardioversion with a high-energy defibrillator (150-200 J on biphasic and 360 J on monophasic). Delaying defibrillation for 2 minutes or more decreases survival rate compared with patients receiving immediate defibrillation (39,3% vs. 22,2%). Defibrillation requires fewer joules if it is done early. After every shock, chest compressions should be performed, along with oxygen delivery and intravenous injection of vasopressors and antiarrhythmic drugs.

Option B: The most common indications for permanent pacemaker implantation are sinus node dysfunction (SND) and high-grade atrioventricular (AV) block. Pacemakers are electronic devices that stimulate the heart with electrical impulses to maintain or restore a functional heartbeat. Pacemakers were initially external and involved the placement of subcutaneous electrodes for patients with inappropriate intrinsic cardiac pacemaker activity and/or abnormal conducting tissue.

Option D: Epinephrine would stimulate an already excitable ventricle and is contraindicated. There are no absolute contraindications against using epinephrine. Some relative contraindications include hypersensitivity to sympathomimetic drugs, closed-angle glaucoma, anesthesia with halothane. Another unique contraindication to be aware of is catecholaminergic polymorphic ventricular tachycardia. As is the case with prescribing any medication, all practitioners should use clinical judgment and evaluate the benefits versus risks with epinephrine.

Dysrhythmias & EKG Interpretation Q 15

noreply@blogger.com (Surendra Tetarwal) — Thu, 28 Apr 2022 23:45:00 +0530

A nurse is caring for a client with unstable ventricular tachycardia. The nurse instructs the client to do which of the following, if prescribed, during an episode of ventricular tachycardia?

A. Breathe deeply, regularly, and easily.

B. Inhale deeply and cough forcefully every 1 to 3 seconds.

C. Lie down flat in bed.

D. Remove any metal jewelry.

Correct Answer: B. Inhale deeply and cough forcefully every 1 to 3 seconds.

Cough Cardiopulmonary Resuscitation (CPR) sometimes is used in the client with unstable ventricular tachycardia. The nurse tells the client to use cough CPR, if prescribed, by inhaling deeply and coughing forcefully every 1 to 3 seconds. Cough CPR may terminate the dysrhythmia or sustain the cerebral and coronary circulation for a short time until other measures can be implemented. A nurse or physician can instruct and coach the patients to cough forcefully every one to three seconds during the initial seconds of a sudden arrhythmia. But because it’s not effective in all patients, it shouldn’t delay definitive treatment.

Option A: Asymptomatic patients with non-sustained ventricular tachycardia (VT) and no underlying cardiac comorbidities require no additional therapy. Patients that are symptomatic and without cardiac comorbidities should be started on a beta-blocker due to favorable efficacy and safety profile.

Option C: If these patients continue to have episodes of non-sustained VT despite beta-blocker therapy, or cannot tolerate beta-blocker therapy, a calcium channel with atrioventricular nodal action such as verapamil or diltiazem can be used.

Option D: Patients with sustained monomorphic ventricular tachycardia (SMVT) that are unstable should be managed following advanced cardiac life support (ACLS) guidelines. Hemodynamically stable patients should be pharmacologically cardioverted using an antiarrhythmic medication. Intravenous amiodarone or procainamide can be used for this purpose.

Dysrhythmias & EKG Interpretation Q 16

noreply@blogger.com (Surendra Tetarwal) — Thu, 28 Apr 2022 23:15:00 +0530

A client is having frequent premature ventricular contractions. A nurse would place a priority on the assessment of which of the following items?

A. Blood pressure and peripheral perfusion.

B. Sensation of palpitations.

C. Causative factors such as caffeine.

D. Precipitating factors such as infection.

Correct Answer: A. Blood pressure and peripheral perfusion.

Premature ventricular contractions can cause hemodynamic compromise. The shortened ventricular filling time with the ectopic beats leads to decreased stroke volume and, if frequent enough, to decreased cardiac output. Physical examination findings would reveal an irregular heart rhythm upon auscultation if the patient is experiencing PVCs during the examination. In some patients, cannon A waves may cause chest or neck discomfort. Otherwise, there would not be any direct physical examination findings. A prolonged run of PVCs can result in hypotension.

Option B: The client may be asymptomatic or may feel palpitations. A thorough history should include any associated symptoms with the palpitations, the patient’s medical history, medication, and supplement usage as well as a detailed social history. It is crucial to inquire about any illicit drug use in those who frequently experience PVCs.

Option C: Common known etiologies include excess caffeine consumption, excess catecholamines, high levels of anxiety, and electrolyte abnormalities. Specific electrolyte changes found in those who experience PVCs are low blood potassium, low blood magnesium, and high blood calcium. Alcohol, tobacco, and illicit drugs are also associated with PVCs as are stimulant-based medications. Patients suffering from sleep deprivation also experience PVCs.

Option D: PVCs can be caused by cardiac disorders or by any number of physiological stressors, such as infection, illness, surgery, or trauma, and by the intake of caffeine, alcohol, or nicotine. There are numerous cardiac and non-cardiac pathologies that are causative of PVCs. Examples include cardiomyopathy, mitral valve prolapse, and myocardial infarction. Any structural heart disease that alters conduction pathways due to tissue alterations can cause PVCs. Non-cardiac examples are hyperthyroidism, anemia, and even hypertension.

Dysrhythmias & EKG Interpretation Q 17

noreply@blogger.com (Surendra Tetarwal) — Thu, 28 Apr 2022 22:45:00 +0530

A client has developed atrial fibrillation, which has a ventricular rate of 150 beats per minute. A nurse assesses the client for:

A. Hypotension and dizziness

B. Nausea and vomiting

C. Hypertension and headache

D. Flat neck veins

Correct Answer: A. Hypotension and dizziness

The client with uncontrolled atrial fibrillation with a ventricular rate more than 150 beats a minute is at risk for low cardiac output because of loss of atrial kick. The nurse assesses the client for palpitations, chest pain or discomfort, hypotension, pulse deficit, fatigue, weakness, dizziness, syncope, shortness of breath, and distended neck veins. A physical exam should always begin with the assessment of airway breathing and circulation as it is going to affect the decision making regarding management. On general physical examination, patients may have tachycardia with an irregularly irregular pulse.

Option B: The presentation of AF can range from asymptomatic to devastating complications such as cardiogenic shock and ischemic stroke. A complete history should focus on symptoms such as palpitations, chest pain, shortness of breath, increased lower extremity swelling, dyspnea on exertion, and dizziness.

Option C: In addition, history is imperative in identifying risk factors such as hypertension, history of valvular, structural, or ischemic heart disease, obstructive sleep apnea, obesity hypoventilation syndrome, smoking, alcohol intake, illicit drug use, history of rheumatic fever/heart disease, history of pericarditis, and hyperlipidemia.

Option D: The physical exam should focus on identifying the cause of AF. For instance, examining the neck of the patient may give some clues regarding carotid artery disease or thyroid problems. The pulmonary examination may reveal signs of heart failure in the form of rales, and the presence of wheeze may indicate antecedent pulmonary diseases such as asthma and chronic obstructive pulmonary disease (COPD).

Dysrhythmias & EKG Interpretation Q 18

noreply@blogger.com (Surendra Tetarwal) — Thu, 28 Apr 2022 22:15:00 +0530

A nurse is watching the cardiac monitor, and a client’s rhythm suddenly changes. There are no P waves; instead, there are wavy lines. The QRS complexes measure 0.08 second, but they are irregular, with a rate of 120 beats a minute. The nurse interprets this rhythm as:

A. Sinus tachycardia

B. Atrial fibrillation

C. Ventricular tachycardia

D. Ventricular fibrillation

Correct Answer: B. Atrial fibrillation

Atrial fibrillation is characterized by a loss of P waves; an undulating, wavy baseline; QRS duration that is often within normal limits; and an irregular ventricular rate, which can range from 60 to 100 beats per minute (when controlled with medications) to 100 to 160 beats per minute (when uncontrolled). Atrial fibrillation is the most common type of cardiac arrhythmia. It is the leading cardiac cause of stroke. Risk factors for atrial fibrillation include advanced age, high blood pressure, underlying heart and lung disease, congenital heart disease, and increased alcohol consumption.

Option A: Sinus tachycardia is a regular cardiac rhythm in which the heart beats faster than normal and results in an increase in cardiac output. While it is common to have sinus tachycardia as a compensatory response to exercise or stress, it becomes concerning when it occurs at rest.

Option C: Ventricular tachycardia is characterized by the absence of P waves, wide QRS complexes (usually greater than 0.14 second), and a rate between 100 and 250 impulses per minute. The rhythm is usually regular. Ventricular tachycardia is characterized as a wide complex (QRS duration greater than 120 milliseconds) tachyarrhythmia at a heart rate greater than 100 beats per minute. It is classified by duration as non-sustained or sustained. Non-sustained ventricular tachycardia is defined as more than 3 beats of ventricular origin at a rate greater than 100 beats per minute that lasts less than 30 seconds in duration.

Option D: VF is a WCT caused by irregular electrical activity and characterized by a ventricular rate of usually greater than 300 with discrete QRS complexes on the electrocardiogram (ECG). QRS morphology in VF varies in shape, amplitude, and duration with a prominent irregular rhythm.

Dysrhythmias & EKG Interpretation Q 19

noreply@blogger.com (Surendra Tetarwal) — Thu, 28 Apr 2022 21:45:00 +0530

A client with rapid rate atrial fibrillation asks a nurse why the physician is going to perform carotid massage. The nurse responds that this procedure may stimulate the:

A. Vagus nerve to slow the heart rate.

B. Vagus nerve to increase the heart rate; overdriving the rhythm.

C. Diaphragmatic nerve to slow the heart rate.

D. Diaphragmatic nerve to overdrive the rhythm.

Correct Answer: A. Vagus nerve to slow the heart rate.

Carotid sinus massage is one of the maneuvers used for vagal stimulation to decrease a rapid heart rate and possibly terminate a tachydysrhythmias. The others include inducing the gag reflex and asking the client to strain or bear down. Medication therapy often is needed as an adjunct to keep the rate down or maintain the normal rhythm. Vagal maneuvers are techniques used to increase vagal parasympathetic tone in an attempt to diagnose and treat various arrhythmias. They are often utilized first in an effort to abort episodes of stable supraventricular tachycardia (SVT) or differentiate SVT from ventricular tachycardias (VT).

Option B: Vagal maneuvers, including Carotid Sinus Massage and Valsalva Maneuver, transiently increase the arterial pressure in the carotid sinuses and aortic arch. This action triggers the baroreceptor reflex, which results in increased parasympathetic output to the heart via the vagus nerve (cranial nerve X).

Option C: The location of the carotid sinus is at the bifurcation of the internal and external carotid artery from the common carotid artery. The sinus contains baroreceptors that sense changes in blood pressure. Afferent signals are then transmitted via the glossopharyngeal nerve (cranial nerve IX) to the nucleus tractus solitarius (NTS) within the medulla.

Option D: Within the heart, the right vagus nerve serves to stimulate the sinoatrial (SA) node, the pacemaker of the healthy heart, in the right atrium; this causes slowed electrical activity within the SA node. The left vagus nerve mostly innervates atrioventricular (AV) node, which slows conduction between the atria and the ventricles. The end product of vagal stimulation is a decrease in the speed and frequency of electrical impulses in the heart, which could ultimately slow or terminate a tachydysrhythmia.

Heart Failure & Valvular Diseases Q 1

noreply@blogger.com (Surendra Tetarwal) — Thu, 28 Apr 2022 21:15:00 +0530

Which of the following actions is the first priority of care for a client exhibiting signs and symptoms of coronary artery disease?

A. Decrease anxiety.

B. Enhance myocardial oxygenation.

C. Administer sublingual nitroglycerin.

D. Educate the client about his symptoms.

Correct Answer: B. Enhance myocardial oxygenation.

Enhancing myocardial oxygenation is always the first priority when a client exhibits signs or symptoms of cardiac compromise. Without adequate oxygenation, the myocardium suffers damage. The desired effect is to decrease myocardial oxygen demand by decreasing ventricular stress. Drugs with negative inotropic properties can decrease perfusion to the already ischemic myocardium. A combination of nitrates and beta-blockers may have cumulative effects on cardiac output.

Option A: Promote expression of feelings and fears. Let the patient/SO know these are normal reactions. Unexpressed feelings may create internal turmoil and affect self-image. Verbalization of concerns reduces tension, verifies the level of coping, and facilitates dealing with feelings. The presence of negative self-talk can increase the level of anxiety and may contribute to an exacerbation of angina attacks.

Option C: Sublingual nitroglycerin is administered to treat acute angina, but the administration isn’t the first priority. Nitroglycerin has been the standard for treating and preventing anginal pain for more than 100 yr. Today it is available in many forms and is still the cornerstone of antianginal therapy.

Option D: Although educating the client is important in care delivery, it is not a priority when a client is compromised. Discuss the pathophysiology of condition. Stress the need for preventing and managing anginal attacks. Patients with angina need to learn why it occurs and what they can do to control it. This is the focus of therapeutic management to reduce the likelihood of myocardial infarction and promote a healthy heart lifestyle.

Heart Failure & Valvular Diseases Q 2

noreply@blogger.com (Surendra Tetarwal) — Thu, 28 Apr 2022 20:45:00 +0530

What is the first intervention for a client experiencing MI?

A. Administer morphine

B. Administer oxygen

C. Administer sublingual nitroglycerin

D. Obtain an ECG

Correct Answer: B. Administer oxygen

Administering supplemental oxygen to the client is the first priority of care. The myocardium is deprived of oxygen during an infarction, so additional oxygen is administered to assist in oxygenation and prevent further damage. Supplemental oxygen is indicated in patients with hypoxemia (SaO2 <90% or PaO2 <60mm Hg).

Option A: The chest pain due to myocardial infarction is associated with sympathetic arousal, which causes vasoconstriction and increased workload for the ischemic heart. Intravenous opioids (e.g., morphine) are the analgesics most commonly used for pain relief (Class IIa).

Option C: Nitro is also used to treat MI, but they’re more commonly administered after the oxygen. Intravenous nitrates are more effective than sublingual nitrates with regard to symptom relief and regression of ST depression (NSTEMI). The dose is titrated upward until symptoms are relieved, blood pressure is normalized in hypertensive patients, or side effects such as a headache and hypotension are noted.

Option D: An ECG is the most common diagnostic tool used to evaluate MI. The resting 12 lead ECG is the first-line diagnostic tool for the diagnosis of acute coronary syndrome (ACS). It should be obtained within 10 minutes of the patient’s arrival in the emergency department. Acute MI is often associated with dynamic changes in the ECG waveform.

Heart Failure & Valvular Diseases Q 3

noreply@blogger.com (Surendra Tetarwal) — Thu, 28 Apr 2022 20:15:00 +0530

Which of the following classes of medications protects the ischemic myocardium by blocking catecholamines and sympathetic nerve stimulation?

A. Beta-adrenergic blockers

B. Calcium channel blockers

C. Narcotics

D. Nitrates

Correct Answer: A. Beta-adrenergic blockers

Beta-adrenergic blockers work by blocking beta receptors in the myocardium, reducing the response to catecholamines and sympathetic nerve stimulation. They protect the myocardium, helping to reduce the risk of another infarction by decreasing myocardial oxygen demand. Beta-blockers also decrease blood pressure via several mechanisms, including decreased renin and reduced cardiac output. The negative chronotropic and inotropic effects lead to a decreased oxygen demand; that is how angina improves after beta-blocker usage.

Option B: Calcium channel blockers reduce the workload of the heart by decreasing the heart rate. The non-dihydropyridines have inhibitory effects on the sinoatrial (SA), and atrioventricular (AV) nodes are resulting in a slowing of cardiac conduction and contractility. This allows for the treatment of hypertension, reduces oxygen demand, and helps to control the rate in tachydysrhythmias.

Option C: Narcotics reduce myocardial oxygen demand, promote vasodilation, and decrease anxiety. There are three opioid receptors: mu, kappa, and delta. Mu receptors mediate most of the clinical and adverse effects of opioids: analgesia, sedation, euphoria, constipation, and respiratory distress. Activation of kappa receptors also leads to analgesia, dyspnea, and sedation.

Option D: Nitrates reduce myocardial oxygen consumption by decreasing left ventricular end-diastolic pressure (preload) and systemic vascular resistance (afterload). The venodilation increases the venous capacitance and lowers the preload; this subsequently lowers the left ventricular end-diastolic pressure, resulting in a reduction in myocardium workload, which decreases the oxygen demand of the heart.

Heart Failure & Valvular Diseases Q 4

noreply@blogger.com (Surendra Tetarwal) — Thu, 28 Apr 2022 19:45:00 +0530

What is the most common complication of an MI?

A. Cardiogenic shock

B. Heart failure

C. Arrhythmias

D. Pericarditis

Correct Answer: C. Arrhythmias

Arrhythmias, caused by oxygen deprivation to the myocardium, are the most common complication of an MI. About 90% of patients who have an acute myocardial infarction (AMI) develop some form of cardiac arrhythmia during or immediately after the event. In 25% of patients, such rhythm abnormalities manifest within the first 24 hours. In this group of patients, the risk of serious arrhythmias, such as ventricular fibrillation, is greatest in the first hour and declines thereafter.

Option A: Cardiogenic shock, another complication of an MI, is defined as the end stage of left ventricular dysfunction. This condition occurs in approximately 15% of clients with MI. Cardiogenic shock is a physiologic state in which inadequate tissue perfusion results from cardiac dysfunction, most often systolic. It is a major, and frequently fatal, complication of a variety of acute and chronic disorders, occurring most commonly following acute myocardial infarction (MI).

Option B: Because the pumping function of the heart is compromised by an MI, heart failure is the second most common complication. Myocardial infarction (MI) remains the most common cause of heart failure (HF) worldwide. For almost 50 years HF has been recognized as a determinant of adverse prognosis after MI, but efforts to promote myocardial repair have failed to translate into clinical therapies.

Option D: Pericarditis most commonly results from a bacterial or viral infection but may occur after the MI. Pericardial inflammation after myocardial infarction can be either acute seen after 3 to 10 days after large transmural myocardial infarction, termed as peri-infarction pericarditis, or immune-mediated inflammation after 1 to 8 weeks termed as post-myocardial infarction syndrome (Dressler syndrome). The pain of pericarditis may be confused as resulting from post-infarction angina or recurrent infarction.

Heart Failure & Valvular Diseases Q 5

noreply@blogger.com (Surendra Tetarwal) — Thu, 28 Apr 2022 19:15:00 +0530

With which of the following disorders is jugular vein distention most prominent?

A. Abdominal aortic aneurysm

B. Heart failure

C. MI

D. Pneumothorax

Correct Answer: B. Heart failure

Elevated venous pressure, exhibited as jugular vein distention, indicates a failure of the heart to pump. Increased blood volume, which can occur with heart failure, or anything that interferes with filling of the right atrium or movement of the blood into the right ventricle, can increase the central venous pressure and the amount of jugular vein distention.

Option A: The aorta is the largest blood vessel in the body. It delivers oxygenated blood from the heart to the rest of the body. An aortic aneurysm is a bulging, weakened area in the wall of the aorta. Over time, the blood vessel balloons and is at risk for bursting (rupture) or separating (dissection). This can cause life-threatening bleeding and potentially death.

Option C: An MI, if severe enough, can progress to heart failure, however, in and of itself, an MI doesn’t cause JVD. In patients with acute inferior-wall MI with right ventricular involvement, distention of neck veins is commonly described as a sign of failure of the right ventricle. Impaired right ventricular function also leads to systemic venous hypertension, edema, and hepatomegaly.

Option D: JVD isn’t a symptom of pneumothorax. Tension pneumothorax presents with respiratory distress, jugular venous distention (JVD), diminished breath sounds, tachycardia, and narrow pulse pressure. Although tracheal deviation and jugular venous distention are commonly cited signs of this condition, they both occur late in the condition.

Heart Failure & Valvular Diseases Q 6

noreply@blogger.com (Surendra Tetarwal) — Thu, 28 Apr 2022 18:45:00 +0530

Toxicity from which of the following medications may cause a client to see a green-yellow halo around lights?

A. digoxin (Lanoxin)

B. furosemide (Lasix)

C. metoprolol (Lopressor)

D. enalapril (Vasotec)

Correct Answer: A. digoxin (Lanoxin)

One of the most common signs of digoxin toxicity is the visual disturbance known as the “green-yellow halo sign.” Digoxin’s therapeutic half-life is between 30 to 40 hours, but this may change in overdose. Digoxin excretion is primarily renal, and for this reason, patients with poor or worsening renal function, such as patients who are elderly or have CKD, are more likely to develop toxicity. The other medications aren’t associated with such an effect.

Option B: Toxicity with furosemide manifests as extensions of its diuretic activity. Signs and symptoms of overdose or toxicity include dehydration, reduced blood volume, and electrolyte imbalances. Risk of hypokalemia increases with the use of a high dose of furosemide, decreased oral intake of potassium, in patients with hyperaldosteronism states (liver abnormalities or licorice ingestion) or concomitant use of corticosteroid, ACTH, and laxatives.

Option C: The primary adverse effects of metoprolol include heart failure exacerbation, fatigue, depression, bradycardia or heart block, hypotension, bronchospasm, cold extremities, dizziness, decreased libido, diarrhea, tinnitus, decreased exercise tolerance, glucose intolerance, and may mask hypoglycemia.

Option D: The side effect most commonly encountered with the use of ACE inhibitors is cough. The cough is characteristically non-productive and stops with the discontinuation of the drug. Other adverse effects of enalapril are hypotension, hyperkalemia, angioedema, cholestatic jaundice, and hypersensitivity reaction. Vasodilation caused by enalapril to reduce the afterload of heart and decrease the total peripheral resistance is also responsible for hypotension.