Ch 23 PrepU: Management of Patients with Coronary Vascular Disorders

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Ischemic myocardial tissue changes cause elevation of the ST segment, an inverted T wave, and a pathological Q wave. A prolonged PR interval occurs with first-degree heart block, the least dangerous atrioventricular heart block; this disorder may arise in healthy people but sometimes results from drug toxicity, electrolyte or metabolic disturbances, rheumatic fever, or chronic degenerative disease of the conduction system. An absent Q wave is normal; an MI may cause a significant Q wave. A widened QRS complex indicates a conduction delay in the His-Purkinje system.

A client comes to the emergency department reporting chest pain. An electrocardiogram (ECG) reveals myocardial ischemia and an anterior-wall myocardial infarction (MI). Which ECG characteristic does the nurse expect to see?

Reduce risk through education, support, and physical activity. Cardiac rehabilitation is targeted at risk reduction through education, individual and group support, and physical activity. Cardiac rehabilitation should aid in lowering cholesterol levels, not increasing them. Cardiac rehabilitation is not focused on returning to the pre-illness lifestyle. Lifestyle choices likely contributed to the cardiac event and need to be changed. Cardiac rehabilitation doesn't eliminate atherosclerosis. Although it may lower blood pressure, that isn't the primary purpose of cardiac rehabilitation.

A client diagnosed with a myocardial infarction (MI) has begun a cardiac rehabilitation program. The nurse recognizes which overall goal as a focus of rehabilitation for a client who has had an MI?

Clopidogrel Because of the risk of thrombus formation following a coronary stent placement, the patient receives antiplatelet medications, such as clopidogrel or aspirin. Isosorbide mononitrate is a nitrate used for vasodilation. Metoprolol is a beta blocker used for relaxing blood vessels and slowing heart rate. Diltiazem is a calcium channel blocker used to relax heart muscles and blood vessels.

A client had a percutaneous transluminal coronary angioplasty (PTCA). What medication will the nurse administer to prevent thrombus formation in the stent?

The client should be instructed about side effects of the medication, which include flushing, throbbing headache, and tachycardia. The client should renew the nitroglycerin supply every 6 months. If the pain is severe, the client can crush the tablet between the teeth to hasten sublingual absorption. Tablets should never be removed and stored in metal or plastic pillboxes. Nitroglycerin is very unstable and should be carried in its original container.

A client has been recently placed on nitroglycerin. Which instruction by the nurse should be included in the client's teaching plan?

Prinzmetal angina results from coronary artery spasm. Activities that increase myocardial oxygen demand may trigger angina of effort. An unpredictable amount of activity may precipitate unstable angina. Worsening angina is brought on by the same type or level of activity that caused previous angina episodes; anginal pain becomes increasingly severe.

A client is admitted for treatment of Prinzmetal angina. When developing this client's care plan, the nurse should keep in mind that this type of angina is a result of what trigger?

"Removing the patch at night prevents drug tolerance while keeping the benefits." Tolerance to antianginal effects of nitrates can occur when taking these drugs for long periods of time. Therefore, to prevent tolerance and maintain benefits, it is a common regime to remove transdermal patches at night. Common adverse effects of nitroglycerin are headaches and contact dermatitis but not the reason for removing the patch at night. It is true that while the client rests, there is less demand on the heart but not the primary reason for removing the patch.

A client is ordered a nitroglycerine transdermal patch for treatment of CAD and asks the nurse why the patch is removed at bedtime. Which is the best response by the nurse?

A transdermal nitroglycerin patch is prescribed for the prevention of angina pectoris. Nitroglycerin transdermal patches are typically applied for 12 to 14 hours, and then removed for the same amount of time. Though it is true that common adverse effects of nitroglycerin are headaches and contact dermatitis and that there is less demand on the heart when the client rests, these are not the reasons for applying and removing the patch for the same length of time in a 24-hour period.

A client is prescribed a nitroglycerin transdermal patch to treat angina. Which statement does the nurse include when reinforcing medication teaching to the client prior to discharge?

Blood pressure 84/52 mm Hg Hypotension and headache are the most common adverse effects of nitroglycerin. Therefore, blood pressure is the vital sign most likely to reflect an adverse effect of this drug. The nurse should check the client's blood pressure 1 hour after administering nitroglycerin ointment. A blood pressure decrease of 10 mm Hg is within the therapeutic range. If blood pressure falls more than 20 mm Hg below baseline, the nurse should remove the ointment and report the finding to the physician immediately. An above-normal heart rate (tachycardia) is a less common adverse effect of nitroglycerin. Respiratory rate and temperature don't change significantly after nitroglycerin administration.

A client is receiving nitroglycerin ointment to treat angina pectoris. The nurse evaluates the therapeutic effectiveness of this drug by assessing the client's response and checking for adverse effects. Which vital sign is most likely to reflect an adverse effect of nitroglycerin?

History of a prior intracranial hemorrhage is an absolute contraindication for thrombolytic therapy. An allergy to iodine, shellfish, radiographic dye, and latex are of primary concern before a cardiac catheterization but not a known contraindication for thrombolytic therapy. Administration of a thrombolytic agent with heparin increases risk of bleeding; the primary healthcare provider usually discontinues the heparin until thrombolytic treatment is completed.

A client presents to the ED with a myocardial infarction. Prior to administering a prescribed thrombolytic agent, the nurse must determine whether the client has which absolute contraindication to thrombolytic therapy?

sublingual nitroglycerin, tissue plasminogen activator (tPA), and telemetry The nurse should anticipate an order for sublingual nitroglycerin, tPA, and telemetry, as the client's chest pain began 4 hours before diagnosis. The preferred choice is tPA, which is more specific for cardiac tissue than streptokinase. Stress testing shouldn't be performed during an MI. The client doesn't exhibit symptoms that indicate the use of lidocaine.

A client was chopping firewood and experienced a heaviness in the chest and dyspnea. The client arrives in the emergency department four hours after the heaviness and the health care provider diagnoses an anterior myocardial infarction (MI). What orders will the nurse anticipate?

chest pain that occurs at rest and usually in the middle of the night A client with Prinzmetal's angina will complain of chest pain that occurs at rest, usually between 12 and 8:00 AM, is sporadic over 3-6 months, and diminishes over time. Clients with stable angina generally experience chest pain that lasts 15 minutes or less and may radiate. Clients with Cardiac Syndrome X experience prolonged chest pain that accompanies exercise and is not always relieved by medication. Clients with unstable angina experience chest pain of increased frequency, severity, and duration that is poorly relieved by rest or oral nitrates.

A client who has been diagnosed with Prinzmetal's angina will present with which symptom?

A client with angina pectoris should stop smoking at once because smoking increases the blood carboxyhemoglobin level; this increase, in turn, reduces the heart's oxygen supply and may induce angina. The client must seek immediate medical attention if chest pain doesn't subside after three nitroglycerin doses taken 5 minutes apart; serious myocardial damage or even sudden death may occur if chest pain persists for 2 hours. To improve coronary circulation and promote weight management, the client should get regular daily exercise. The client should eat plenty of fiber, which may decrease serum cholesterol and triglyceride levels and minimize hypertension, in turn reducing the risk for atherosclerosis (which plays a role in angina).

A client with angina pectoris must learn how to reduce risk factors that exacerbate this condition. When developing the client's care plan, which expected outcome should a nurse include?

Carvedilol A client with suspected myocardial infarction should receive aspirin, nitroglycerin, morphine, and a beta-adrenergic blocker such as carvedilol. Digoxin treats arrhythmias; there is no indication that the client is having arrhythmias. Furosemide is used to treat signs of heart failure, which isn't indicated at this point. Nitroprusside increases blood pressure. This client has stable vital signs and isn't hypotensive.

A client with chest pain arrives in the emergency department and receives nitroglycerin, morphine, oxygen, and aspirin. The health care provider diagnoses acute coronary syndrome. When the client arrives on the unit, vital signs are stable and the client does not report any pain. In addition to the medications already given, which medication does the nurse expect the health care provider to order?

"I should expect a low-grade fever and swelling at the site for the next week." Fever and swelling at the site are signs of infection and should be reported to the physician. Showers should be taken until the insertion site is healed. Prolonged sitting can result in thrombosis formation. Bruising at the insertion site is common and may take from 1 to 3 weeks to resolve.

A client, who has undergone a percutaneous transluminal coronary angioplasty (PTCA), has received discharge instructions. Which statement by the client would indicate the need for further teaching by the nurse?

Decreases resting heart rate The therapeutic effects of beta-adrenergic blocking agents such as metoprolol are to reduce myocardial oxygen consumption by blocking beta-adrenergic sympathetic stimulation to the heart. The result is reduced heart rate, slowed conduction of impulses through the conduction system, decreased blood pressure, and reduced myocardial contractility to balance the myocardial oxygen needs and amount of oxygen available. This helps to control chest pain and delays the onset of ischemia during work or exercise. This classification of medication also reduces the incidence of recurrent angina, infarction, and cardiac mortality. In general, the dosage of medication is titrated to achieve a resting heart rate of 50-60 bpm. Metoprolol is not administered to decrease cholesterol levels, increase cardiac output, or decrease platelet aggregation.

A nurse is caring for a client who experienced an MI. The client is ordered to receive metoprolol. The nurse understands that this medication has which therapeutic effect?

Assess the client's level of pain and administer prescribed analgesics. The cardinal symptom of MI is persistent, crushing substernal pain or pressure. The nurse should first assess the client's pain and prepare to administer nitroglycerin or morphine for pain control. The client must be medically stabilized before pulmonary artery catheterization can be used as a diagnostic procedure. Anxiety and a feeling of impending doom are characteristic of MI, but the priority is to stabilize the client medically. Although the client and family members should be kept informed at every step of the recovery process, this action isn't the priority when treating a client with a suspected MI.

A nurse is caring for a client who is exhibiting signs and symptoms characteristic of a myocardial infarction (MI). Which statement describes priorities the nurse should establish while performing the physical assessment?

The client demonstrates ability to tolerate more activity without chest pain. The ability to tolerate more activity without chest pain indicates a favorable response to therapy in a client who is recovering from an MI or who has a history of coronary artery disease. The client should have a normal electrocardiogram with no arrhythmias and a regular heart rate of 60 to 100 beats/minute. Smoking is a cardiovascular risk factor that the client must be willing to eliminate. A client who responds favorably to therapy shouldn't have chest pain.

A nurse is evaluating a client who had a myocardial infarction (MI) 7 days earlier. Which outcome indicates that the client is responding favorably to therapy?

A cholinergic blocking agent may cause dry mouth and delay the sublingual absorption of nitroglycerin. The nurse should offer the client sips of water before administering nitroglycerin. Amantadine, digoxin, and diphenhydramine can interact with a cholinergic blocking agent but not through delayed absorption. Amantadine and diphenhydramine enhance the effects of anticholinergic agents.

A nurse reviews a client's medication history before administering a cholinergic blocking agent. Adverse effects of a cholinergic blocking agent may delay absorption of what medication?

Apply manual pressure at the site of the insertion of the sheath. The immediate nursing action would be to apply pressure to the femoral site. Reviewing blood studies will not stop the bleeding. The nurse cannot decrease anticoagulation therapy independently. If the bleeding does not stop, the health care provider needs to be notified.

After percutaneous transluminal coronary angioplasty (PTCA), the nurse confirms that a client is experiencing bleeding from the femoral site. What will be the nurse's initial action?

Leads V3 and V4 Leads V3 and V4 record electrical events in the septal region of the left ventricle. Leads I, aVL, V5, and V6 record electrical events on the lateral surface of the left ventricle. Leads II, III, and aVF record electrical events on the inferior surface of the left ventricle. Leads V1 and V2 record electrical events on the anterior surface of the right ventricle and the anterior surface of the left ventricle.

An electrocardiogram (ECG) taken during a routine checkup reveals that a client has had a silent myocardial infarction. Changes in which leads of a 12-lead ECG indicate damage to the left ventricular septal region?

Assess for factors that may be causing the client's delirium. Uncharacteristic changes in cognition following cardiac surgery are suggestive of delirium. Dementia has a gradual onset with organic brain changes and is not an acute response to surgery. Assessment is a higher priority than reorientation, which may or may not be beneficial. Even though delirium is not rare, it is not considered to be an expected part of recovery.

An older adult is postoperative day one, following a coronary artery bypass graft (CABG). The client's family members express concern to the nurse that the client is uncharacteristically confused. After reporting this change in status to the health care provider, what additional action should the nurse take?

Heparin causes an elevation of the PTT and, thereby, increases the risk for bleeding. With a large cannulation such as a sheath used for angioplasty, the PTT should be 50 seconds or less before the sheath is removed. Removing the sheath before the PTT drops below 50 seconds can cause bleeding at the insertion site. The other PTT results are incorrect for determining when to remove the sheath.

Following a percutaneous transluminal coronary angioplasty, a client is monitored in the postprocedure unit. The client's heparin infusion was stopped 2 hours earlier. There is no evidence of bleeding or hematoma at the insertion site, and the pressure device is removed. With regards to partial thromboplastin time (PTT), when should the nurse plan to remove the femoral sheath?

Beta-adrenergic blockers are used in the treatment of CAD to decrease the consumption of myocardial oxygen by reducing heart rate and workload of the heart. Nitrates are used for vasodilation. Anti-lipid drugs (such as statins and B vitamins) are used to decrease homocysteine levels. ACE inhibitors inhibit the conversion of angiotensin.

In the treatment of coronary artery disease (CAD), medications are often ordered to control blood pressure in the client. Which of the following is a primary purpose of using beta-adrenergic blockers in the nursing management of CAD?

Morphine sulfate not only decreases pain perception and anxiety but also helps to decrease heart rate, blood pressure, and demand for oxygen. Nitrates are administered for vasodilation and pain control in clients with angina-type pain, but oral forms (such as isosorbide dinitrate) have a large first-pass effect, and transdermal patch is used for long-term management. Meperidine hydrochloride is a synthetic opioid usually reserved for treatment of postoperative or migraine pain.

Severe chest pain is reported by a client during an acute myocardial infarction. Which of the following is the most appropriate drug for the nurse to administer?

Arteriosclerosis refers to the loss of elasticity or hardening of the arteries that accompanies the aging process, whereas atherosclerosis is a condition in which the lumen of arteries fills with fatty deposits called plaque. The two terms do not refer to the same disorder, nor can they be used interchangeably. The other responses provide the client with inaccurate information.

The client asks the nurse to explain the difference between arteriosclerosis and atherosclerosis. Which is the best explanation the nurse can give to the client?

Troponin remains elevated for a long period, often as long as 2 weeks, and it therefore can be used to detect recent myocardial damage. Myoglobin peaks within 12 hours after the onset of symptoms. Total creatine kinase (CK) returns to normal in 3 days. CK-MB returns to normal in 3 to 4 days.

The client has had biomarkers tested after reporting chest pain. Which diagnostic marker of myocardial infarction remains elevated for as long as 2 weeks?

The abrupt stop can cause a myocardial infarction. Beta blockers do not cause the formation of blood clots, internal bleeding, or the onset of a migraine headache.

The client is prescribed nadolol for hypertension. What is the reason the nurse will teach the client not to stop taking the medication abruptly?

Metoprolol works at beta 1 -receptor sites. Most beta1-receptor sites are located in the heart. Beta2-receptor sites are located in the uterus, blood vessels, and bronchi.

The nurse is administering oral metoprolol. Where are the receptor sites mainly located?

pericardial friction rub Post-pericardiotomy syndrome is characterized by fever, pericardial pain, pleural pain, dyspnea, pericardial effusion, pericardial friction rub, and arthralgia. Leukocytosis (elevated WBCs) occurs, along with elevation of the ESR. Hypothermia is not a symptom of post-pericardiotomy syndrome.

The nurse is assessing a client with suspected post-pericardiotomy syndrome after cardiac surgery. What manifestation will alert the nurse to this syndrome?

Check blood pressure. During a bronchoscopy, a vasovagal response may be caused by stimulating the pharynx, and it in turn may cause stimulation of the vagus nerve. The client may, therefore, experience a sudden drop in heart rate, leading to syncope. The nurse will need to assess blood pressure to assure circulation. Stimulation of the vagus nerve doesn't lead to pupillary dilation or bronchodilation. Stimulation of the vagus nerve increases gastric secretions.

The nurse is assisting with a bronchoscopy at the bedside in a critical care unit. The client experiences a vasovagal response. What should the nurse do next?

Atherosclerosis (plaque formation) is the leading cause of CAD. Diabetes mellitus is a risk factor for CAD, but it isn't the most common cause. Myocardial infarction is a common result of CAD. Renal failure doesn't cause CAD, but the two conditions are related.

The nurse is caring for a client diagnosed with coronary artery disease (CAD). What condition most commonly results in CAD?

Avoid continuous BP monitoring The client receiving heparin receives bleeding precautions, which can include applying pressure to the site of any needle punctures for a longer time than usual, avoiding intramuscular injections, and avoiding tissue injury and bruising from trauma or constrictive devices (e.g., continuous use of an automatic BP cuff). Subcutaneous injections are permitted; a soft toothbrush should be used, and the client may use nail clippers, but with caution.

The nurse is caring for a client diagnosed with unstable angina who is receiving IV heparin. The client requires bleeding precautions. Bleeding precautions include which measure?

Protamine sulfate is known as the antagonist for unfractionated heparin (it neutralizes heparin). Alteplase is a thrombolytic agent. Clopidogrel is an antiplatelet medication that is given to reduce the risk of thrombus formation after coronary stent placement. The antiplatelet effect of aspirin does not reverse the effects of heparin.

The nurse is caring for a client following a coronary artery bypass graft (CABG). The nurse notes persistent oozing of bloody drainage from various puncture sites. The nurse anticipates that the physician will order which medication to neutralize the unfractionated heparin the client received?

ST Elevation The first signs of an acute MI are usually seen in the T wave and the ST segment. The T wave becomes inverted; the ST segment elevates (it is usually flat). An elevated ST segment in two contiguous leads is a key diagnostic indicator for MI (i.e., ST-elevation MI). This client requires immediate invasive therapy or fibrinolytic medications. Although the other ECG findings require intervention, elevated ST elevations require immediate and definitive interventions.

The nurse is caring for a client presenting to the emergency department (ED) reporting chest pain. Which electrocardiographic (ECG) finding would be most concerning to the nurse?

anxiety, diaphoresis, tachycardia, cool & clammy skin

The nurse is caring for a client who is demonstrating signs of acute coronary syndrome (ACS). Which assessment findings indicate to the nurse that the client is experiencing stimulation of the sympathetic nervous system? Select all that apply.

enhance myocardial oxygenation Enhancing myocardial oxygenation is always the first priority when a client exhibits signs or symptoms of cardiac compromise. Without adequate oxygen, the myocardium suffers damage. A nurse administers sublingual nitroglycerin to treat acute angina pectoris, but its administration isn't the first priority. Although educating the client and decreasing anxiety are important in care, neither is a priority when a client is compromised.

The nurse is caring for a client with coronary artery disease. What is the nurse's priority goal for the client?

adequate cough and gag reflexes, acceptable arterial ABGs, and breathing without the assistance of the ventilator Before being extubated, the client should have cough and gag reflexes and stable vital signs; be able to lift the head off the bed or give firm hand grasps; have adequate vital capacity, negative inspiratory force, and minute volume appropriate for body size; and have acceptable arterial blood gas levels while breathing without the assistance of the ventilator. Inability to talk is expected when intubated with an endotracheal tube.

The nurse is caring for a ventilated client after coronary artery bypass graft surgery. What are the criterions for extubation for the client? Select all that apply.

substernal in location, sudden in onset and prolonged in duration, and viselike and radiates to the shoulders and arms Chest pain that occurs suddenly, continues despite rest and medication, is substernal, and is sometimes viselike and radiating to the shoulders and arms is associated with an MI. Angina pectoris pain is generally relieved by rest and nitroglycerin.

The nurse is educating a patient diagnosed with angina pectoris about the difference between the pain of angina and a myocardial infarction (MI). How should the nurse describe the pain experienced during an MI? (Select all that apply.)

Complications that may occur following a PTCA include myocardial ischemia, bleeding and hematoma formation, retroperitoneal hematoma, arterial occlusion, pseudoaneurysm formation, arteriovenous fistula formation, and acute renal failure. The urine output of 40 mL over a 2-hour period may indicate acute renal failure. The client is expected to have a minimum urine output of 30 mL/h. Dried blood at the insertion site is a finding that warrants no acute intervention. A serum potassium level of 4.0 mEq/L is within the normal range. The heart rate of 100 bpm is within the normal range and indicates no acute distress.

The nurse is reevaluating a client 2 hours after a percutaneous transluminal coronary angioplasty (PTCA) procedure. Which assessment finding may indicate the client is experiencing a complication of the procedure?

Often, women and elderly do not have the typical chest pain associated with a myocardial infarction. Some report vague symptoms (fatigue, abdominal pain), which can lead to misdiagnosis. Some older adults may experience little or no chest pain. Gender is not a contributing factor for fatal occurrence but rather a result of symptoms association.

The nurse knows that women and older adult are at greater risk for a fatal myocardial event. Which factor is the primary contributor of this cause?

percutaneous coronary intervention (PCI). The client with a STEMI is often taken directly to the cardiac catheterization laboratory for an immediate PCI. Superior outcomes have been reported with the use of PCI compared to thrombolytics. IV heparin and IV nitroglycerin are used to treat NSTEMI.

The nurse recognizes that the treatment for a non-ST-elevation myocardial infarction (NSTEMI) differs from that for a STEMI, in that a STEMI is more frequently treated with

Anything over 100 mg/dL

What is considered a high LDL level?

"See if rest relieves the chest pain before using the nitroglycerin." Decreased activity may relieve chest pain; sitting will prevent injury should the nitroglycerin lower BP and cause fainting. The client should expect to feel dizzy or flushed or to develop a headache following sublingual nitroglycerin use. The client should place one nitroglycerin tablet under the tongue if 2-3 minutes of rest fails to relieve pain. Clients may take up to three nitroglycerin tablets within 5 minutes of each other to relieve angina. However, they should call 911 if the three tablets fail to resolve the chest pain.

When providing discharge instructions for a client who has been prescribed sublingual nitroglycerin for angina, the nurse should plan to include which instructions?

Cardiac tamponade is fluid and clot accumulation in the pericardial sac, which compresses the heart, preventing the blood from filling the ventricles. Fluid overload is exhibited by high pulmonary artery wedge pressure, central venous pressure, and pulmonary artery diastolic pressure, as well as crackles in the lungs. Hypertension results from postoperative vasoconstriction. Hypothermia is a low body temperature that leads to vasoconstriction.

Which complication of cardiac surgery occurs when fluid and clots accumulate in the pericardial sac, which compresses the heart, preventing blood from filling the ventricles?

CRP is a marker for inflammation of the vascular endothelium. LDL, HDL, and triglycerides are not markers of vascular endothelial inflammation. They are elements of fat metabolism.

Which is a diagnostic marker for inflammation of vascular endothelium?

Clopidogrel or ticlopidine is given to clients who are allergic to aspirin or are given in addition to aspirin to clients who are at high risk for MI. Amlodipine, diltiazem, and felodipine are calcium channel blockers.

Which medication is given to clients who are diagnosed with angina but are allergic to aspirin?

The nurse knows to withhold the anticoagulant therapy to decrease chance of hemorrhage during the procedure. The nurse does inform the client of diagnostic test, will assess pulses, and prep the skin prior to the angioplasty, but this is not the most important action to be taken.

Which nursing actions would be of greatest importance in the management of a client preparing for angioplasty?

Preinfarction angina is also known as unstable angina. Stable angina has predictable and consistent pain that occurs upon exertion and is relieved by rest. Variant angina is exhibited by pain at rest and reversible ST-segment elevation. Silent angina manifests through evidence of ischemia, but the client reports no symptoms.

Which term refers to preinfarction angina?

Notify the health care provider. Because heparin can cause bleeding gums that may indicate excessive anticoagulation, the nurse should notify the health care provider, who will evaluate the client's condition. The health care provider should order laboratory tests such as partial thromboplastin time before concluding that the client's bleeding is significant. The ordered heparin dose may be therapeutic rather than excessive, so the nurse shouldn't discontinue the heparin infusion unless the health care provider orders this after evaluating the client. Protamine sulfate, not a coumarin derivative, is given to counteract heparin. Heparin doesn't normally cause bleeding gums.

While receiving a heparin infusion to treat deep vein thrombosis, a client reports bleeding in the gums when brushing teeth. What should the nurse do first?


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