NCLEX: Care of the Client with Cardiovascular Disorders

Care of the Client with Cardiovascular Disorders: Ventricular Tachycardia

Focus topic: Care of the Client with Cardiovascular Disorders

Ventricular rhythms are those originating in the ventricle. These rhythms can result in decreased oxygen perfusion to the body and possible death.

Ventricular Rhythm Characteristics

Care of the Client with Cardiovascular Disorders

Because ventricular tachycardia is lethal, the item writers for NCLEX might ask the student to identify an ECG rhythm. It should be noted that ventricular tachycardia is a rapid irregular rhythm with the absence of a P wave. The rate can be 250 bpm, and the SA node continues to discharge independently of the ventricle. Ventricular tachycardia is often associated with valvular heart disease, heart failure, hypomagnesium, hypotension, and ventricular aneurysms.

Care of the Client with Cardiovascular Disorders

Evidence of ventricular tachycardia.

 

Care of the Client with Cardiovascular Disorders: Ventricular Fibrillation

Focus topic: Care of the Client with Cardiovascular Disorders

Ventricular fibrillation (V-fib) s the primary mechanism associated with sudden cardiac arrest. This disorganized chaotic rhythm results in a lack of pumping activity of the heart. Without effective pumping, no oxygen is sent to the brain and other vital organs. If this condition is not corrected quickly, the client’s heart stops beating and asystole is seen on the ECG. The client quickly becomes faint, loses consciousness, and becomes pulseless. Hypotension, or a lack of blood pressure, and abnormal heart sounds are present.

Care of the Client with Cardiovascular Disorders

Treatment of ventricular fibrillation is done with a defibrillator set at approximately 200 joules. Three quick, successive shocks are delivered, with the third at 360 joules. If a defibrillator is not readily available, a precordial thump can be delivered. If cardiac arrest occurs, the nurse should initiate cardiopulmonary resuscitation (CPR) and be ready to administer first-line drugs such as epinephrine or vasopressin (Pitressin).

Care of the Client with Cardiovascular Disorders: Internal Pacemaker/Internal Cardiac Defibrillators

Focus topic: Care of the Client with Cardiovascular Disorders

An internally implanted pacemaker and cardioverter/defibrillator are used to treat ventricular fibrillation, heart block, and other dysrhythmias. These devices are usually implanted on the client’s left side and are connected to the myocardium with electrical leads. If the client experiences fibrillation or ventricular tachycardia, the defibrillator delivers a shock to the heart and corrects the pattern. The internal defibrillator also records dysrhythmias the client has experienced so that the physician is aware of her condition. A client with an internal cardiac defibrillator or permanent pacemaker should be taught to

  • Avoid elevating her left arm above her head for approximately two weeks or until the doctor instructs otherwise.
  • Wear a medic alert stating that a pacemaker/internal defibrillator is implanted. Identification will alert the healthcare worker so that alterations in care can be made.
  • Take pulse for one full minute and report the rate to the physician.
  • Avoid applying pressure over the pacemaker. Pressure on the defibrillator or pacemaker can interfere with the electrical leads.
  • Inform her dentist of the presence of a pacemaker because electrical devices are often used in dentistry.
  • Avoid having a magnetic resonance imaging (MRI) test. Magnetic resonance interferes with the electrical impulse of the implant.
  • Avoid close contact with electrical appliances, electrical or gasoline engines, transmitter towers, antitheft devices, metal detectors, and welding equipment because they can interfere with conduction.
  • Be careful when using microwaves. Microwaves are generally safe for use, but the client should be taught to stand approximately five feet away from the device while cooking.
  • Report fever, redness, swelling, or soreness at the implantation site.
  • If beeping tones are heard coming from the internal defibrillator, the client should immediately move away from any electromagnetic source. She should stand clear from other people because shock can affect anyone touching the client during defibrillation.
  • Report dizziness, fainting, weakness, blackouts, or a rapid pulse rate. The client will most likely be told not to drive a car for approximately three months after the internal defibrillator is inserted to evaluate any dysrhythmias.
  • Report persistent hiccupping because this can indicate a misfiring of the pacemaker/internal defibrillator.
Care of the Client with Cardiovascular Disorders

Care of the Client with Cardiovascular Disorders: Cardiopulmonary Resuscitation

Focus topic: Care of the Client with Cardiovascular Disorders

The American Heart Association (AHA) releases new guidelines for professionals and the public periodically, so the graduate nurse should review the changes for updates.

Care of the Client with Cardiovascular Disorders

Care of the Client with Cardiovascular Disorders: Angina Pectoris

Focus topic: Care of the Client with Cardiovascular Disorders

Angina pectoris is defined as chest pain caused by disruption of the balance and demand for oxygen by the heart. This disruption results in a lack of oxygen to the myocardium.

Several risk factors predispose the client to cardiac ischemia. These include

  • Hypertension
  • Hyperlipidemia
  • Smoking
  • Obesity
  • Familial history
  • Diabetes
  • Anemia
  • Stress

The nurse caring for the client with angina pectoris assesses the type and location of chest pain. The pain is usually located in the substernal to retrosternal area and radiates down the left arm and to the jaw or shoulder. The onset is usually precipitated by a large meal, exertion, stress, anxiety, smoking, alcohol, or drugs, and it might occur immediately when the client awakens. The client’s skin is usually warm and dry, but it might be cool and clammy. He might complain of nausea and vomiting and gripping chest pain.

Women, the elderly, and diabetics frequently do not complain of the typical chest pain associated with angina but might complain of fatigue and shortness of breath. An ECG often reveals S-T segment depressions and T wave inversion; there might be S-T depressions. If the client has Prinzmetal’s angina, there might be an elevation in the S-T segment.

Treatment involves the application of oxygen and the administration of nitroglycerine sublingually, topically, or intravenously. The client should be taught to take one nitroglycerine tablet sublingually every five minutes, not to exceed three tablets. If the first tablet does not relieve the pain, a second can be taken. If the pain is still not relieved after taking three tablets, the client should go directly to the hospital or call an ambulance. The client should be taught to replenish his supply of nitroglycerine every six months and protect the pills from light by leaving them in the brown bottle. It is important for the client to understand that light decreases the effectiveness of nitroglycerine. Nitroglycerine patches and creams should be applied to dry skin. The site should be relatively free of hair. Most resources suggest that the hair should be clipped and not shaved because shaving might abrade the skin and cause irritation. Nurses should always wear gloves when applying nitroglycerine creams or patches to prevent application of the medication to themselves. Intravenous nitroglycerine must be administered with an infusion rate controller.

Care of the Client with Cardiovascular Disorders: Myocardial Infarction

Focus topic: Care of the Client with Cardiovascular Disorders

When there is a disruption in blood supply to the myocardium, the client is considered to have had a myocardial infarction (MI). Factors contributing to diminished blood flow to the heart include arteriosclerosis, emboli, thrombus, shock, and hemorrhage. If circulation is not quickly restored to the heart, the muscle becomes necrotic. Hypoxia from ischemia can lead to vasodilation. Acidosis associated with electrolyte imbalances often occurs, and the client can slip into cardiogenic shock.

The most common site for an MI is the left ventricle. Only 10% of clients report the classic symptoms of a myocardial infarction. Women often fail to report chest pain and, if they do, they might tell the nurse that the pain is beneath the shoulder or in the back. Clients with diabetes have fewer pain receptors and might report little or no pain.

The most commonly reported signs and symptoms associated with MI include

  • Substernal pain or pain over the precordium for a duration greater than 15 minute
  • Pain that is described as heavy, vise-like, and radiating down the left arm
  • Pain that begins spontaneously and is not relieved by nitroglycerin or rest
  • Pain that radiates to the jaw and neck
  • Pain that is accompanied by shortness of breath, pallor, diaphoresis, dizziness, nausea, and vomiting
  • Increased heart rate, decreased blood pressure, increased temperature, and increased respiratory rate

Care of the Client with Cardiovascular Disorders: Diagnosis of Myocardial Infarction

Focus topic: Care of the Client with Cardiovascular Disorders

The diagnosis of a myocardial infarction is made by looking at both the ECG and the cardiac profile that consist of the cardiac enzymes. The following are the most commonly used diagnostic tools for determining the type and severity of MI:

  • Electrocardiogram
  • Serum enzymes and isoenzymes

Other tests that are useful in providing a complete picture of the client’s condition are white blood cell count (WBC), sedimentations rate, and blood urea nitrogen (BUN).

The best serum enzymes used to diagnose myocardial infarction are creatine kinase (CKMB), troponin T and 1, CRP, and LDH. The enzyme CKMB is released when there is damage to the myocardium and elevates quickly. The troponin T and 1 are specific to striated muscle and are often used to determine the severity of the attack. Troponin T and 1 can remain elevated for as long as two weeks following the MI. C-reactive protein (CRP) levels are used with the CKMB to determine whether the client has had an acute MI and the severity of the infarction. Lactic dehydrogenase (LDH) is a nonspecific enzyme that is elevated with any muscle trauma.

Care of the Client with Cardiovascular Disorders: Management of a Client with Myocardial Infarction

Focus topic: Care of the Client with Cardiovascular Disorders

Management of a client with myocardial infarction includes monitoring of blood pressure, oxygen levels, and pulmonary artery wedge pressures. Because the blood pressure can fall rapidly, medication such as dopamine is prescribed. Other medications are ordered to relieve pain and to vasodilate the coronary vessels—for example, morphine sulfate IV is ordered for pain. Thrombolytics, such as streptokinase, will most likely be ordered. Early diagnosis and treatment significantly improve the client’s prognosis. A client suffering an MI can present with dysrhythmias. Ventricular dysrhythmias, such as ventricular tachycardia or fibrillation, can lead to cardiac stand-still and death if not treated quickly.

A client with an MI should be given small, frequent meals. The diet should be low in sodium, fat, and cholesterol. Adequate amounts of fluid and fiber are encouraged to prevent constipation. Stool softeners are often ordered to prevent straining during defe- cation. Post-MI teaching should stress the importance of a regular program of exercise, stress reduction, regular bowel elimination, and cessation of smoking. Because caffeine causes vasoconstriction, caffeine intake should be limited. The client can resume sexual activity in six weeks or when he is able to climb a flight of stairs without experiencing chest pain. Medications such as sildenafil (Viagra) can lead to uncontrolled hypotension if taken within 24 hours of taking a nitrite. For this reason, the client should be taught to consult the cardiologist if taking Viagra. Clients should be taught not to perform the Valsalva maneuver or bend at the waist to retrieve items from the floor. Placing items in top drawers helps to prevent increased intrathoracic pressure. The client will probably be discharged on an anticoagulant such as aspirin, clopidogrel (Plavix), enoxaparin (Lovenox), or sodium warfarin (Coumadin).

Care of the Client with Cardiovascular Disorders

Care of the Client with Cardiovascular Disorders: Exercise Electrocardiography

Focus topic: Care of the Client with Cardiovascular Disorders

An exercise electrocardiography test, also known as a stress test or an exercise tolerance test, helps to determine the function of the heart during exercise. The client is instructed to eat a light meal and refrain from smoking or consuming caffeine the morning of the test. Prior to the test, the cardiologist assesses the heart using an ECG tracing and blood pressure monitor. The client then walks on a treadmill or bicycles at a steadily progressing rate of speed of 1–10 miles per hour and can also be adjusted from flat to inclined. She is asked to report any shortness of breath or chest pain. Abnormalities can then be assessed. The client continues the test until

  • A rapid heart rate is reached and maintained.
  • Signs or symptoms of chest pain; fatigue; or extreme dyspnea, hypotension, or ventricular dyshythmias appear on the ECG.
  • S-T segment depressions are noted on the ECG.

The client remains in the unit for approximately 2 hours after the test to ensure that there are no signs of hypotension or cardiac dyshythmias. Due to mobility problems, some clients are not able to walk on the treadmill or ride the bicycle. Cardiac stimulants are then used to induce stress. An example of medications used is dobutamine (Dobutrex).

A Cardiolite scan is a scan that is done in conjunction with a treadmill test and ECG to evaluate the blood flow though the coronary arteries. Cardiolite is injected intravenously to stress the heart. Persantine, a vasodilator, is used for non-stress studies. Persantine is injected to increase blood flow to the coronary vessels while scans are done to determine blockages.

Care of the Client with Cardiovascular Disorders: Echocardiography

Focus topic: Care of the Client with Cardiovascular Disorders

Echocardiography is a noninvasive test used to determine the size of the ventricle, the functionality of the valves, and the size of the heart. There is no special preparation for the echocardiography, and this test takes only 30–60 minutes. A transesophageal echocardiography is a more invasive method of assessing the structures of the heart. A transducer is placed into the esophagus or stomach to examine the posterior cardiac structures. This test requires that the client be NPO after midnight the day of the procedure and the throat be anesthetized to prevent stimulation of the gag reflex. Following the procedure, the client is checked for return of the gag reflex prior to offering food.

Care of the Client with Cardiovascular Disorders

Care of the Client with Cardiovascular Disorders: Cardiac Catheterization

Focus topic: Care of the Client with Cardiovascular Disorders

Cardiac catheterization is used to detect blockages associated with myocardial infarction and dysrhythmias. Cardiac catheterization, as with any other dye procedure, requires a signed consent. This procedure can also accompany percutaneous transluminal coronary angioplasty. Prior to and following this procedure, the nurse should

  • Assess for allergy to iodine or shellfish.
  • Maintain the client on bed rest for approximately 8 hours after the test with the leg straight.
  • Maintain pressure on the access site after the procedure for at least five minutes or until no signs of bleeding are noted. Many cardiologists use a device called an Angio-Seal to prevent bleeding at the insertion site. The device creates a mechanical seal, anchoring a collagen sponge to the site. The sponge absorbs in 60–90 days.
  • Use pressure dressing and/or ice packs to control bleeding after the test.
  • Check distal pulses after the procedure because diminished pulses can indicate a hematoma at the catheter insertion site and should be reported immediately.
  • Force fluids to clear dye from the body after the test.

Care of the Client with Cardiovascular Disorders: Percutaneous Transluminal Coronary Angioplasty and Stent Placement

Focus topic: Care of the Client with Cardiovascular Disorders

A percutaneous transluminal coronary angioplasty (PTCA) is a less invasive procedure than coronary artery bypass surgery. Many clients are relieved of chest pain following this procedure. Clients with noncalcified lesions, such as plaque, benefit most from a PTCA and recover relatively quickly.

During the procedure, the physician inserts a catheter while visualizing the coronary vessels. A balloon is used to push plaque into the wall of the vessel. A stent might be placed in the artery following the balloon procedure. A stent is a mesh tube usually made of stainless steel. This tube is inserted following an angioplasty to prevent restenosis.

When angiography indicates that the vessel is 50% or more open, the procedure is complete. An IV of heparin is administered in a continuous infusion. Nitroglycerin or sublingual nifedipine is often given to prevent spasms of the myocardium.

Care of the Client with Cardiovascular Disorders: Coronary Artery Bypass Graft

Focus topic: Care of the Client with Cardiovascular Disorders

When the client does not respond to medical management of a coronary artery occlusion and is experiencing chest pain, the physician might perform coronary artery bypass graft (CABG) surgery. The decision to perform a CABG is based on the results of the cardiac catheterization. If the client has the following symptoms, a CABG might be performed:

  • Angina with greater than 50% blockage of the left anterior descending artery
  • Unstable angina with two vessels severely blocked or three vessels moderately blocked
  • Ischemia of the myocardium
  • Has had an acute MI
  • Has ischemia following an angiography or PTC

During a coronary artery bypass, a sternal incision is performed and a donor vessel is removed. A common vessel used to bypass a blockage in the coronary arteries is the saphenous vein located in the back of the leg. Other vessels, such as the mammary artery and the radial artery, can also be used to bypass the blockage. When the client is asleep, the team of surgeons goes to work harvesting the donor vessel while another team prepares to place the client on the cardiopulmonary bypass machine. The cardiopulmonary bypass machine is often used to provide oxygen to the lungs and body during the time that the heart is stopped.

Blood that is heparinized and oxygenated passes through the machine and back into the client by way of the ascending aortic vessel or the femoral artery. While the client is on the bypass machine, the core body temperature is lowered to approximately 85° F. The rationale for lowering the body temperature is that the body’s oxygen needs are lowered when the body is cooled. A potassium solution is used to bathe the heart and help prevent dysrhythmias. After the heart is stopped, the surgeon anastomoses the donor vessel to bypass the blockage. When the procedure is finished, the client is warmed and transported to the intensive care unit.

The family should be instructed that the client will return to the intensive care unit with several tubes and monitors. The client will have mediastinal tubes to drain fluid from the chest cavity. The client might also have chest tubes if reinflation of the lungs was necessary. If the client bleeds and the blood is not drained from the mediastinal area, fluid accumulates around the heart and cardiac tamponade results. If this occurs, the myocardium becomes compressed and the accumulated fluid prevents the filling of the ventricles and decreases cardiac output.

During surgery, a Swan-Ganz catheter for monitoring central venous pressure— pulmonary artery wedge pressure—is inserted in the pulmonary artery. A radial arterial blood pressure monitor is inserted to measure vital changes in the client’s blood pressure. An ECG monitor and oxygen saturation monitor are also used. Other tubes used to assess and stabilize the client are a nasogastric tube to decompress the stomach, an endotracheal tube to assist in ventilation, and a Foley catheter to measure hourly urinary output.

Some clients experience depression or recurrent nightmares following coronary artery bypass graft surgery. The family should be made aware that this is a common problem and that this problem might take several months to resolve. It is important to tell both the family and the patient to notify the surgeon if these experiences occur.

Cardiac rehabilitation is recommended and includes a plan of exercise, diet, and weight reduction. The client should be taught regarding the need to stop smoking and to moderate alcohol consumption. Drugs used to treat sexual dysfunction, such as Viagra, should not be used within 24 hours of taking nitrites such as nitroglycerine.

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