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1ST SEMESTER A.Y. 2024-2025 |MEDSURG 3 - LEC Nursing Care of At-Risk and Sick Adult Clients with Alterations in the Cardio-Pulmonary System I. NURSING CARE OF AT-RISK AND SICK ADULT 3 L...

1ST SEMESTER A.Y. 2024-2025 |MEDSURG 3 - LEC Nursing Care of At-Risk and Sick Adult Clients with Alterations in the Cardio-Pulmonary System I. NURSING CARE OF AT-RISK AND SICK ADULT 3 LAYERS CLIENTS WITH ALTERATIONS IN THE CARDIO- Endocardium (Innermost) – Consists of PULMONARY SYSTEM endothelial tissue and lines the inside of the A. Review of Anatomy and Physiology of the Cardio-Pulmonary System heart and valves. B. Application of Nursing Process of the Cardio- Myocardium (Middle) – Made up of muscle Pulmonary System Disorder fibers and is responsible for the pumping C. Pathophysiology of the Cardio-Pulmonary action. System Disorder Epicardium (Outermost) – Exterior layer of the D. Diagnostic and Laboratory Procedures of the heart. Cardio-Pulmonary Disorders 4 HEART CHAMBERS REVIEW OF ANATOMY AND PHYSIOLOGY OF THE CARDIO- PULMONARY SYSTEM ANATOMY OF THE HEART Hollow, muscular organ located in the center of the thorax, where it occupies the space between the lungs (mediastinum) and rests on the diaphragm. Weighs approximately 300 g (10.6 oz). Great vessel and chamber pressures. Pressures are identified The heart pumps blood to the tissues, supplying in mm Hg as mean pressure or systolic over diastolic pressure. them with oxygen and other nutrients. Right Atrium – Receives oxygen-poor blood Pericardium – Thin, fibrous sac that encased from the body. the heart. Right Ventricle – Pumps oxygen-poor blood to The space between these two layers the lungs. (pericardial space) is normally filled with Left Atrium – Receives oxygen-rich blood from about 20 mL of fluid. the lungs. Left Ventricle – Pumps oxygen-rich blood to the body. HEART VALVES ATRIOVENTRICULAR (AV) VALVES Separate the atria from the ventricles. Tricuspid Valve (3 cusps/leaflet) – Separates the right atrium from the right ventricle. Mitral or Bicuspid Valve (2 cusps) – Lies between the left atrium and the left ventricle. SEMILUNAR (SL) VALVES Composed of three leaflets, which are shaped like half-moons; closed during diastole. Pulmonic Valve – Valve between the right ventricle and the pulmonary artery. Structure of the heart. @chadrayg 1 MEDSURG 3 - LEC 1ST SEMESTER | Nursing Care: Alterations in Cardio-Pulmonary System Aortic Valve – Valve between the left ventricle Repolarization – Return of cell to resting state and the aorta. caused by re-entry of K into a cell while Na CORONARY ARTERIES exits the cell. The left and right coronary arteries and their branches supply arterial blood to the heart. MYOCARDIUM Middle, muscular layer of the atrial and ventricular walls. Composed of specialized cells called myocytes, which form an interconnected network of muscle fibers. Cardiac action potential of a fast-response Purkinje fiber. The arrows indicate the approximate time and direction of movement of each ion influencing membrane potential. Ca FUNCTION OF THE HEART movement out of the cell is not well defined but is thought to occur during phase 4. CARDIAC ELECTROPHYSIOLOGY Phase 0: Cellular Depolarization – Positive ions influx into the cell (Na+) Phase 1: Early Cellular Repolarization – K+ exits the intracellular space. Phase 2: Plateau Phase – Ca+ ions enter the intracellular space. Phase 3: Completion of Repolarization/ Late – Return of the cell to its resting state. Phase 4: Resting Phase REFRACTORY PERIODS Cardiac conduction system. AV, atrioventricular; SA, sinoatrial. Sinoatrial (SA) Node – Start of impulse; Myocardial cells must completely repolarize primary pacemaker of the heart. before they can depolarize again. Atrioventricular (AV) Node – Coordinates the Effective (or Absolute) Refractory Period incoming electrical impulses from the atria Cell is completely unresponsive to any and after a slight delay (allowing the atria electrical stimulus; it is incapable of time to contract and complete ventricular initiating an early depolarization. filling) relays the impulse to the ventricles. Corresponds with the time in phase 0 to the middle of phase 3 of the action potential. Bundle of His – Impulse is conducted through a bundle of specialized conducting tissue, Relative Refractory Period which then divides into the right bundle branch Corresponds with the short time at the end (conducting impulses to the right ventricle) and of phase 3. the left bundle branch (conducting impulses to If an electrical stimulus is stronger than the left ventricle). normal, the cell may depolarize prematurely. Purkinje Fibers – Impulses travel through the bundle branches to reach the terminal point in CARDIAC HEMODYNAMICS the conduction system. CARDIAC OUTPUT CARDIAC ACTION POTENTIAL Total amount of blood ejected by one of the Resting Phase: PISO ventricles in liters per minute. Potassium (K) Inside CO in a resting adult is 4-6 L/min. Sodium (Na) Outside CO = SV x HR Depolarization – Electrical activation of a cell STROKE VOLUME caused by influx of Na into the cell while K Amount of blood ejected from one of the exits the cell. ventricles per heartbeat. SV in a resting adult is about 60-130 mL. @chadrayg 2 MEDSURG 3 - LEC 1ST SEMESTER | Nursing Care: Alterations in Cardio-Pulmonary System EFFECT OF STROKE VOLUME ON CARDIAC COMMON SYMPTOMS OUTPUT Chest pain or discomfort. Primarily determined by three factors: Shortness of breath or dyspnea. preload, afterload, and contractility. Peripheral edema and weight gain. Preload Palpitations (tachycardia from a variety of Degree of stretch of the ventricular cardiac causes). muscle fibers at the end of diastole. Unusual fatigue. The end of diastole is the period when Dizziness, syncope, or changes in level of filling volume in the ventricles is the highest consciousness. and the degree of stretch on the muscle *Symptoms of ACS can differ between men fibers is the greatest. and women. The volume of blood within the ventricle at PAST HEALTH, FAMILY, AND SOCIAL the end of diastole determines preload, HISTORY which directly affects stroke volume. MEDICATIONS Commonly referred to as left ventricular end-diastolic pressure (LVEDP). The nurse solicits answers to the following Frank-Starling (or Starling) Law – As the questions to ensure that patients are safely volume of blood returning to the heart and effectively taking their medications: increases, muscle fiber stretch also increases What are the names and doses of your (increased preload), resulting in stronger medications? contraction and a greater stroke volume. What is the purpose of each of these Afterload medications? Amount of resistance to ejection of blood How and when are these medications from the ventricle. taken? Do you ever skip a dose or forget to Second determinant of stroke volume. take them? Are there any special precautions The resistance of the systemic BP to left ventricular ejection is called systemic associated with any of these medications? vascular resistance. What symptoms or problems do you need to The resistance of the pulmonary BP to right report to your primary provider? ventricular ejection is called pulmonary NUTRITION vascular resistance. Dietary modifications, exercise, weight loss, Contractility and careful monitoring are important Force generated by the contracting strategies for managing three major myocardium. cardiovascular risk factors: hyperlipidemia, Contractility is enhanced by circulating hypertension, and diabetes mellitus. catecholamines, sympathetic neuronal ELIMINATION activity, and certain medications (e.g., Typical bowel and bladder habits. digoxin [Lanoxin], dopamine [Intropin], or Nocturia (awakening at night to urinate) is dobutamine [Dobutrex]). common in patients with HF. Increased circulatory volume is excreted by ASSESSMENT OF THE the kidneys (increased urine production). CARDIOVASCULAR SYSTEM When straining during defecation, the patient bears down (Valsalva maneuver), which momentarily increases pressure on the HEALTH HISTORY baroreceptors. Demographic information. ACTIVITY AND EXERCISE Family/genetic history. The nurse determines if there are recent Cultural/social factors. changes by comparing the patient’s current @chadrayg 3 MEDSURG 3 - LEC 1ST SEMESTER | Nursing Care: Alterations in Cardio-Pulmonary System activity level with that performed in the past 6- BLOOD CHEMISTRY, HEMATOLOGY, AND 12 months. COAGULATION STUDIES Activity-induced angina or shortness of breath Lipid Profile – Cholesterol, triglycerides, and may indicate CAD. lipoproteins. Fatigue, associated with a low left ventricular Brain (B-type) Natriuretic Peptide (BNP) – ejection fraction (less than 40%). Neurohormone that helps regulate BP and fluid SLEEP AND REST volume. Orthopnea – Need to sit upright or stand to C-REACTIVE PROTEIN avoid feeling short of breath. Used as adjunct to other tests to predict CVD Paroxysmal Nocturnal Dyspnea – Sudden risk. awakening with shortness of breath. HOMOCYSTEINE SELF-PERCEPTION AND SELF-CONCEPT Amino acid linked to the development of Questions for Health History Taking: atherosclerosis. What is your cardiac condition? How has this illness changed your feelings CHEST X-RAY AND FLUOROSCOPY about your health? Chest X-Ray – Obtained to determine the size, What do you think caused this illness? contour, and position of the heart. What consequences do you think this illness It reveals cardiac and pericardial will have on your physical activity, work, calcifications and demonstrates physiologic social relationships, and role in your alterations in the pulmonary circulation. family? Fluoroscopy – An x-ray imaging technique that How much of an influence do you think you allows visualization of the heart on a screen. have on controlling this illness? It shows cardiac and vascular pulsations SEXUALITY AND REPRODUCTION and unusual cardiac contours. Sexual dysfunction affects 2x as many people with CVD compared with the general ELECTROCARDIOGRAPHY population. 12-lead ECG. In men, erectile dysfunction may develop as a side effect of cardiac medications (e.g., beta- Continuous monitoring: hardwire and blockers). telemetry. Reproductive history is necessary for women Continuous ambulatory monitoring. of childbearing age, particularly those with Wireless mobile monitoring. seriously compromised cardiac function. COPING AND STRESS TOLERANCE CARDIAC STRESS TESTING Anxiety, depression, and stress are known to Exercise Stress Testing – Patient walks or runs influence both the development of and on a treadmill (most common) or pedals a recovery from CAD and HF. stationary bicycle. High levels of anxiety are associated with an Pharmacologic Stress Testing – Vasodilating increased incidence of CAD and in-hospital agents such as dipyridamole, adenosine, or complication rates after MI. regadenoson given as an IV infusion are used to mimic the effects of exercise by maximally dilating normal coronary arteries and DIAGNOSTIC EVALUATION identifying stenotic arteries that cannot vasodilate. LABORATORY TESTS Dobutamine is another option, a synthetic CARDIAC BIOMARKER ANALYSIS sympathomimetic agent that increases heart Creatine kinase (CK), CK isoenzymes (CK-MB), rate, myocardial contractility, and BP. and proteins (myoglobin, troponin T, and troponin I). @chadrayg 4 MEDSURG 3 - LEC 1ST SEMESTER | Nursing Care: Alterations in Cardio-Pulmonary System RADIONUCLIDE IMAGING TRANSESOPHAGEAL ECHOCARDIOGRAPHY Noninvasive tests that use radioisotopes to (TEE) evaluate coronary artery perfusion, detect Involves threading a small transducer through myocardial ischemia and infarction, and/or the mouth and into the esophagus. assess left ventricular function. Provides clearer images because ultrasound Radioisotopes – Unstable atoms that give off waves pass through less tissue. small amounts of energy in the form of gamma rays as they decay. CARDIAC CATHETERIZATION MYOCARDIAL PERFUSION IMAGING Invasive diagnostic procedure in which Performed using two types of techniques: radiopaque arterial and venous catheters are single photon emission computed tomography introduced into selected blood vessels of the (SPECT) or positron emission tomography right and left sides of the heart. (PET). ANGIOGRAPHY SINGLE PHOTON EMISSION COMPUTED A technique in which a contrast agent is TOMOGRAPHY (SPECT) injected into the vascular system to outline the Painless, noninvasive procedure that involves heart and blood vessels. the injection of the nuclear medicine AORTOGRAPHY radionucleotide (technetium-99m [99mTc]; An aortogram is a form of angiography that rubidium-82) and imaging. outlines the lumen of the aorta and the major POSITRON EMISSION TOMOGRAPHY (PET) arteries arising from it. Another noninvasive procedure in which a CORONARY ARTERIOGRAPHY radioactive tracer chemical is administered to Involves the introduction of a catheter into the the patient and images are obtained. right or left brachial or femoral artery, which TEST OF VENTRICULAR FUNCTION AND is then passed into the ascending aorta and WALL MOTION manipulated into the right and left coronary Equilibrium radionuclide angiocardiography arteries. (ERNA), also known as multiple-gated RIGHT HEART CATHETERIZATION acquisition (MUGA) scanning, is a common It involves the passage of a catheter from an noninvasive technique that uses a conventional antecubital or femoral vein into the right scintillation camera interfaced with a atrium, right ventricle, pulmonary artery, and computer to record images of the heart during pulmonary arterioles. several hundred heartbeats. LEFT HEART CATHETERIZATION COMPUTED TOMOGRAPHY (CT) Performed to evaluate the patency of the Also called computerized axial tomographic coronary arteries and the function of the left (CAT) scanning or electron-beam computed ventricle and the mitral and aortic valves. tomography (EBCT), uses x-rays to provide cross-sectional images of the chest, including ELECTROPHYSIOLOGIC TESTING the heart and great vessels. MAGNETIC RESONANCE ANGIOGRAPHY (MRA) Electrophysiology study (EPS) is an invasive procedure that plays a major role in the Noninvasive, painless technique that is used to diagnosis and management of serious examine both the physiologic and anatomic dysrhythmias. properties of the heart. ECHOCARDIOGRAPHY CARDIAC MONITORING Invasive procedure; used to measure cardiac TRANSTHORACIC ECHOCARDIOGRAPHY chamber pressures and assess patency of the Noninvasive ultrasound test that is used to coronary arteries. measure the ejection fraction and examine the size, shape, and motion of cardiac structures. @chadrayg 5 MEDSURG 3 - LEC 1ST SEMESTER | Nursing Care: Alterations in Cardio-Pulmonary System Requires ECG and hemodynamic monitoring; Depolarization – Electrical activation of a cell emergency equipment must be available. caused by influx of Na into the cell while K Assessment prior to test, allergies, and blood exits the cell. work. Repolarization – Return of cell to resting state Assessment of patient after procedure: caused by re-entry of K into a cell while Na circulation, potential for bleeding, potential for exits the cell. dysrhythmias. Cardiac Output – Total amount of blood ejected Activity restrictions. by one of the ventricles in liters per minute. Patient education before and after procedure. Stroke Volume – Amount of blood ejected from HEMODYNAMIC MONITORING one of the ventricles per heartbeat. This type of assessment is achieved by the use Preload – Degree of stretch of the ventricular of direct pressure monitoring systems. cardiac muscle fibers at the end of diastole. CENTRAL VENOUS PRESSURE (CVP) Afterload – Amount of resistance to ejection of blood from the ventricle. Measurement of the pressure in the vena cava or right atrium. Contractility – Ability of the cardiac muscle to shorten in response to an electrical impulse PULMONARY ARTERY PRESSURE Used in critical care for assessing left ventricular function, diagnosing the etiology of shock, and evaluating the patient’s response to medical interventions (e.g., fluid administration, vasoactive medications). INTRA-ARTERIAL BP MONITORING Used to obtain direct and continuous BP measurements in critically ill patients who have severe hypertension or hypotension. KEY POINTS: Heart – Hollow, muscular organ located in the center of the thorax, where it occupies the space between the lungs (mediastinum) and rests on the diaphragm. Pericardium – Thin, fibrous sac that encased the heart. Endocardium (Innermost) – Consists of endothelial tissue and lines the inside of the heart and valves. Myocardium (Middle) – Made up of muscle fibers and is responsible for the pumping action. Epicardium (Outermost) – Exterior layer of the heart. Sinoatrial (SA) Node – Primary pacemaker of the heart, located in the right atrium. Atrioventricular (AV) Node – Secondary pacemaker of the heart, located in the right atrial wall near the tricuspid valve. @chadrayg 6  1ST SEMESTER A.Y. 2024-2025 |MEDSURG 3 - LEC Disorders of the Cardio-Pulmonary System II. DISORDERS OF THE CARDIO-PULMONARY SYSTEM Oxidized LDL is toxic to the endothelial cells A. Cardiovascular Disorders and fuels progression of the atherosclerotic 1. Myocardial Infarction process. 2. Angina Pectoris 3. Congestive Heart Diseases Atheroma or plaque. 4. Buerger’s Disease and Raynaud’s Disease 5. Atherosclerosis 6. Rheumatoid Endocarditis/ Pericarditis/ Myocarditis 7. Arrhythmias/Dysrhythmias B. Pulmonary Disorders 1. Chronic Airway Limitation/ COPD 2. Bronchial Asthma and Status Asthmaticus 3. Pneumonia 4. Pulmonary Tuberculosis 5. Pleural Effusion 6. Atelectasis 7. Pulmonary Edema 8. Pulmonary Embolism 9. Cystic Fibrosis CARDIOVASCULAR DISORDERS CORONARY ARTERY DISEASE (CAD) Most prevalent type of cardiovascular disease in adults. CORONARY ATHEROSCLEROSIS Abnormal accumulation of lipid, or fatty (A, B) Atherosclerosis begins as monocytes and lipids enter the substances, and fibrous tissue in the lining of intima of an injured vessel. Smooth muscle cells proliferate arterial blood vessel walls. within the vessel wall. These substances block and narrow the (C) Contributing to the development of fatty accumulations and atheroma. coronary vessels in a way that reduces blood (D) As the plaque enlarges, the vessel narrows and blood flow flow to the myocardium. decreases, Involves a repetitious inflammatory response (E) The plaque may rupture and a thrombus might form, obstructing blood flow. to injury of the artery wall and subsequent alteration in the structural and biochemical CLINICAL MANIFESTATIONS properties of the arterial walls. Ischemia – Inadequate blood supply that PATHOPHYSIOLOGY deprives the cardiac muscle cells of oxygen needed for their survival. Injury to the vascular endothelium. Angina pectoris – Chest pain that is brought Endothelium change. about by myocardial ischemia. Cessation of normal production of Sudden cardiac death – A decrease in blood antithrombotic and vasodilating agents. supply from CAD may even cause the heart to Presence of inflammation attracts abruptly stop beating. inflammatory cells (macrophages). The most common manifestation of Ingest lipids, becoming “foam cells“ that myocardial ischemia is the onset of chest pain. transport the lipids into the arterial wall. Damage the endothelium by contributing to the oxidation of LDL. @chadrayg 7 MEDSURG 3 - LEC 1ST SEMESTER | Disorders of the Cardio-Pulmonary System DIAGNOSTIC PROCEDURES “Myo“ refers to “muscle“ Blood Test – Can check blood sugar and “Cardio“ refers to “heart“ cholesterol levels. “Infarct“ refers to “death of tissue from lack Electrocardiogram (ECG/EKG) of oxygen“ Echocardiogram Spectrum of ACS: unstable angina, non-ST- Exercise Stress Test segment elevation myocardial infarction Nuclear Stress Test – Shows how blood moves (NSTEMI), and ST-segment elevation to the heart at rest. myocardial infarction (STEMI). Heart CT Scan – Shows calcium deposits and A heart attack usually occurs when a blood clot blockages in the heart arteries. blocks the flow of blood through a coronary Cardiac Catheterization and Angiogram artery – a blood vessel that feeds blood to a MEDICATIONS part of the heart muscle. Cholesterol Medicine (statins, niacin, fibrates, Interrupted blood flow to your heart can and bile acid sequestrants. damage or destroy a part of the heart muscle. Aspirin PATHOPHYSIOLOGY Beta-Blockers Unstable Angina: Reduced blood flow in a coronary artery, often due to rupture of an Calcium Channel Blockers atherosclerotic plaque, but the artery is not Angiotensin-converting enzyme (ACE) Inhibitors completely occluded. and Angiotensin 2 Receptor Blockers (ARBs) This is an acute situation that is sometimes Nitroglycerin referred to as preinfarction angina Ranolazine because the patient will likely have an MI if SURGICAL MANAGEMENT prompt interventions do not occur. Angioplasty and Stenting (PTCA) – Good MI: Plaque rupture and subsequent thrombus treatment option for unstable angina and formation result in complete occlusion of the stable angina. artery, leading to ischemia and necrosis of the Coronary Artery Bypass Surgery – A vein or myocardium supplied by that artery. artery from somewhere else in your body is Vasospasm (sudden constriction or used to bypass a blocked or narrowed heart narrowing) of a coronary artery, artery. decreased oxygen supply (e.g., from acute NURSING MANAGEMENT blood loss, anemia, or low blood pressure), Relieving pain (angina) – Parameters of and increased demand for oxygen (e.g., scaling; take vitals signs and monitor from a rapid heart rate, thyrotoxicosis, or progression. ingestion of cocaine) are other causes of Maintain CO by monitoring patient’s response MI. to drug therapy, take BP and monitor for In each case, a profound imbalance exists changes. between myocardial oxygen supply and Decrease anxiety, encourage patient and demand. significant others to discuss measures. The area of infarction develops over minutes to hours. As the cells are deprived of oxygen, ischemia MYOCARDIAL INFARCTION (MI) develops, cellular injury occurs, and the lack Acute Coronary Syndrome (ACS) – Emergent of oxygen results in infarction, or the death of situation characterized by an acute onset of cells. myocardial ischemia that results in myocardial The expression “time is muscle“ reflects the death (i.e. MI) if definitive interventions do not urgency of appropriate treatment to improve occur promptly. patient outcomes. Myocardial Infarction (Coronary Occlusion/ Approximately every 40 seconds, an American Heart Attack) – Death of heart tissue caused by will have an MI, and many of these people will lack of oxygenated blood flow. die as a result. @chadrayg 8 MEDSURG 3 - LEC 1ST SEMESTER | Disorders of the Cardio-Pulmonary System Early recognition and treatment of patients DIAGNOSTIC TESTS presenting with an MI will improve their ECG chances of survival. Blood Tests – Cardiac enzyme studies CLINICAL MANIFESTATIONS (Troponin I and Troponin T, CK-MB, Myoglobin, Recurrent chest pain (angina) that’s triggered LDH), CBC by exertion and relieved by rest causing Chest X-ray cardiac ischemia. Nuclear Scan – Small amounts of radioactive Pressure, fullness, or a squeezing pain in the material, such as thallium, are injected into center of your chest that lasts for more than a your bloodstream. few minutes Echocardiogram (2D Echo) Pain extending beyond your chest to your Coronary Catheterization (Angiogram) shoulder, arm, back, or even to your teeth and MEDICATIONS jaw. Aspirin – Inhibits blood clotting, thus helping Increasing episodes of chest pain. maintain blood flow through a narrowed Prolonged pain in the upper abdomen, artery. shortness of breath, sweating, impending Thrombolytics – Also called clot-busters, help sense of doom, fainting, nausea, and vomiting. dissolve a blood clot that's blocking blood flow SIGNS AND SYMPTOMS OF HEART ATTACK to your heart. IN WOMEN Super Aspirins – Similar to aspirin to help Abdominal pain or “heartburn“. prevent new clots from forming. These include Clammy skin. medications such as clopidogrel (Plavix) and Lightheadedness or dizziness. others called platelet IIb/IIIa receptor blockers. Unusual or unexplained fatigue. Blood-Thinning Medications (Anticoagulant) – RISK FACTORS Such as heparin, to make your blood less Tobacco Smoke – Damage the interior walls of "sticky" and less likely to form more arteries – including arteries to your heart – dangerous clots allowing deposits of cholesterol and other Pain Reliever – Such as morphine, to alleviate substances. your discomfort Smoking also increases the risk of deadly Nitroglycerin – Temporarily opens at blood clots. improving blood flow to and from your heart. High Blood Pressure Beta Blocker – Help relax your heart muscle, High Blood Cholesterol or Triglyceride Levels – slow your heartbeat, and decrease blood Can deposit in the walls of blood vessels. pressure (Educate patient to change position Lack of Physical Activity – An inactive lifestyle gradually > orthostatic hypotension.) contributes to high blood cholesterol levels and Cholesterol-Lowering Medications – Examples obesity. include statins, niacin, fibrates and bile acid Obesity – Raises the risk of heart disease sequestrants. Help lower levels of unwanted because it's associated with high blood blood cholesterol and may be helpful if given cholesterol levels, high blood pressure, and soon after a heart attack to improve survival. diabetes. SURGICAL AND OTHER PROCEDURES Diabetes Coronary Angioplasty and Stenting (PTA) – Stress - Increases BP. Emergency angioplasty opens blocked coronary arteries, letting blood flow more Alcohol - Excessive drinking can raise your freely to your heart. blood pressure and triglyceride levels, Catheter is equipped with a special balloon increasing your risk of heart attack. tip. Once in position, the balloon tip is briefly Family history of heart attack inflated to open up a blocked coronary Homocysteine, C-reactive protein and artery. fibrinogen @chadrayg 9 MEDSURG 3 - LEC 1ST SEMESTER | Disorders of the Cardio-Pulmonary System Coronary Artery Bypass Surgery – Involves ANGINA sewing veins or arteries in place at a site Type of chest pain or discomfort caused by beyond a blocked or narrowed coronary reduced blood flow to the heart muscles. artery (bypassing the narrowed section), A symptom of coronary artery disease. restoring blood flow to the heart. TYPES OF ANGINA SEX AFTER HEART ATTACK STABLE ANGINA The demands sexual intercourse places on Predictable and consistent pain that occurs on your heart approximate those of taking a brisk exertion and is relieved by rest and/or walk, scrubbing a floor, or climbing one or two nitroglycerin. flight of stairs. Characteristics: In a way, sexual activity parallels any other Develops when your heart works harder. physical exertion – your heart rate, breathing Usually be predicted. rate, and blood pressure level increase. Last short time: 5 minutes or less. Ask your doctor when its safe to resume sexual Might spread to your arms, back, or other activity. areas. NURSING MANAGEMENT (MONA) Triggered by mental or emotional stress. Morphine, Oxygen, Nitroglycerin, and Aspirin. Causes: Initiate oxygen therapy to improve oxygenation Triggered by physical exertion. of ischemic heart muscle. Emotional stress. Pain control via opiate analgesic therapy UNSTABLE ANGINA (PREINFARCTION ANGINA where Morphine is the drug of choice. OR CRESCENDO ANGINA) Vasodilators given as ordered to help reduce oxygen demand and alleviate pain. Symptoms increase in frequency and severity; may not be relieved with rest or nitroglycerin. Offer support and explain procedures to help reduce anxiety and fear, handle patient Characteristics (medical emergency): carefully and obtain baseline vital signs. Occurs even at rest. Document all assessment findings, response Change in your usual pattern of angina. and interventions given. Unexpected. More severe and lasts longer than stable Promote rest by providing an environment angina: as long as 30 minutes. conducive for recovery. Structure and group all nursing intervention to avoid unnecessary Causes: interruptions. Fatty deposits (plaques). Severe anemia, cold temperature, heavy Monitor for changes in mental status and meals, and smoking. headache and report. INTRACTABLE OR REFRACTORY ANGINA Observe for persistent symptoms of ischemia and report immediately. Severe incapacitating chest pain. VARIANT ANGINA (PRINZMETAL’S ANGINA) ANGINA PECTORIS Pain at rest with reversible ST-segment Chest pain brought about by myocardial elevation; thought to be caused by coronary ischemia. artery vasospasm. Characterized by episodes or paroxysms of Characteristics: pain or pressure in the anterior chest. Usually happens when you’re resting. Often severe. Cause is insufficient coronary blood flow, May be relieved by angina medication. resulting in a decreased oxygen supply when there is increased myocardial demand for Causes: oxygen in response to physical exertion or Caused by a spasm in coronary artery. emotional stress. In other words, the need for oxygen exceeds the supply. @chadrayg 10 MEDSURG 3 - LEC 1ST SEMESTER | Disorders of the Cardio-Pulmonary System SILENT ISCHEMIA aspects of the upper arms, usually the left Objective evidence of ischemia (such as arm. electrocardiographic changes with a stress The patient often feels tightness or a heavy test), but patient reports no pain. choking or strangling sensation that has a PATHOPHYSIOLOGY viselike, insistent quality. Angina is usually caused by atherosclerotic A feeling of weakness or numbness in the disease. arms, wrists, and hands, as well as shortness of breath, pallor, diaphoresis, dizziness or Almost invariably, angina is associated with a lightheadedness, and nausea and vomiting significant obstruction of at least one major may accompany the pain. coronary artery. An important characteristic of angina is that it Normally, the myocardium extracts a large subsides with rest or administering amount of oxygen from the coronary nitroglycerin. circulation to meet its continuous demands. Unstable angina is characterized by attacks When there is an increase in demand, flow that increase in frequency and severity and through the coronary arteries needs to be are not relieved by rest and administering increased. nitroglycerin. When there is blockage in a coronary artery, ASSESSMENT AND DIAGNOSTIC FINDINGS flow cannot be increased, and ischemia results. Diagnosis of angina begins with the patient’s history related to the clinical manifestations of Several factors are associated with typical ischemia. anginal pain: Physical exertion, which can precipitate an Laboratory studies are performed; these may attack by increasing myocardial oxygen include CRP and cardiac biomarker values to demand. rule out an ACS. Exposure to cold, which can cause May also be referred for a nuclear scan or vasoconstriction and elevated blood invasive procedure (e.g., cardiac pressure, with increased oxygen demand. catheterization, coronary angiography). Eating a heavy meal, which increases the DIAGNOSTIC TESTS blood flow to the mesenteric area for Electrocardiogram (ECG) digestion, thereby reducing the blood supply Stress test available to the heart muscle; in a severely Echocardiogram compromised heart, shunting of blood for Coronary angiograph digestion can be sufficient to induce anginal Blood tests pain. Cardiac computerized tomography (CT) scan Stress or any emotion-provoking situation, MEDICAL MANAGEMENT causing the release of catecholamines, which increases blood pressure, heart rate, Aspirin – Reduces the ability of your blood to and myocardial workload. clot, making it easier for blood to flow through narrowed heart arteries. Unstable angina is not associated with these listed factors. It may occur at rest. Nitrates – It relaxes and widen your blood vessels, which allows more blood to flow to CLINICAL MANIFESTATIONS your heart muscle. Pain is often felt deep in the chest behind the Beta Blockers – It works by blocking the effects sternum (retrosternal area). of the hormone epinephrine, also known as Chest pain and discomfort. The chest pain adrenaline. As a result, the heart beats more may feel like: slowly and with less force, thereby reducing burning pressure blood pressure. fullness squeezing It also helps blood vessels relax and open Pain or discomfort is poorly localized and may up to improve blood flow, thus reducing or radiate to the neck, jaw, shoulders, and inner preventing angina. @chadrayg 11 MEDSURG 3 - LEC 1ST SEMESTER | Disorders of the Cardio-Pulmonary System Metoprolol (Lopressor, Toprol) and atenolol (Tenormin) reduce myocardial oxygen consumption Statins – Drugs used to lower blood cholesterol. Calcium Channel Blockers – Also called calcium antagonists. It relaxes and widen blood vessels by affecting the muscle cells in the arterial walls. This increases blood flow in your heart, reducing or preventing angina. Amlodipine and felodipine (Plendil) are the calcium channel blockers of choice for patients with heart failure. Angiotensin-Converting Enzyme (ACE) Inhibitors – These drugs help relax blood vessels. It prevents an enzyme in the body from producing angiotensin II. CORONARY ARTERY DISEASE (CAD) Most prevalent type of cardiovascular disease in adults. CORONARY ATHEROSCLEROSIS Abnormal accumulation of lipid, or fatty (A, B) Atherosclerosis begins as monocytes and lipids enter the substances, and fibrous tissue in the lining of intima of an injured vessel. Smooth muscle cells proliferate arterial blood vessel walls. within the vessel wall. These substances block and narrow the (C) Contributing to the development of fatty accumulations and atheroma. coronary vessels in a way that reduces blood (D) As the plaque enlarges, the vessel narrows and blood flow flow to the myocardium. decreases, Involves a repetitious inflammatory response (E) The plaque may rupture and a thrombus might form, obstructing blood flow. to injury of the artery wall and subsequent alteration in the structural and biochemical CLINICAL MANIFESTATIONS properties of the arterial walls. Ischemia – Inadequate blood supply that PATHOPHYSIOLOGY deprives the cardiac muscle cells of oxygen needed for their survival. Injury to the vascular endothelium. Angina pectoris – Chest pain that is brought Endothelium change. about by myocardial ischemia. Cessation of normal production of Sudden cardiac death – A decrease in blood antithrombotic and vasodilating agents. supply from CAD may even cause the heart to Presence of inflammation attracts abruptly stop beating. inflammatory cells (macrophages). The most common manifestation of Ingest lipids, becoming “foam cells“ that myocardial ischemia is the onset of chest pain. transport the lipids into the arterial wall. DIAGNOSTIC PROCEDURES Damage the endothelium by contributing to the Blood Test – Can check blood sugar and oxidation of LDL. cholesterol levels. Oxidized LDL is toxic to the endothelial cells Electrocardiogram (ECG/EKG) and fuels progression of the atherosclerotic process. Echocardiogram Atheroma or plaque. Exercise Stress Test Nuclear Stress Test – Shows how blood moves to the heart at rest. @chadrayg 12 MEDSURG 3 - LEC 1ST SEMESTER | Disorders of the Cardio-Pulmonary System Heart CT Scan – Shows calcium deposits and New York Heart Association (NYHA) Classification of blockages in the heart arteries. Heart Failure Classification Signs and Symptoms Cardiac Catheterization and Angiogram No limitation of physical activity MEDICATIONS I Ordinary activity does not cause undue fatigue, Cholesterol Medicine (statins, niacin, fibrates, palpitation, or dyspnea. Slight limitation of physical activity and bile acid sequestrants. II Comfortable at rest, but ordinary physical activity Aspirin causes fatigue, palpitation, or dyspnea Marked limitation of physical activity Beta-Blockers III Comfortable at rest, but less than ordinary Calcium Channel Blockers activity causes fatigue, palpitation, or dyspnea. Angiotensin-converting enzyme (ACE) Inhibitors Unable to carry out any physical activity without discomfort and Angiotensin 2 Receptor Blockers (ARBs) IV Symptoms of cardiac insufficiency at rest Nitroglycerin If any physical activity is undertaken, discomfort Ranolazine is increased. SURGICAL MANAGEMENT PATHOPHYSIOLOGY Angioplasty and Stenting (PTCA) – Good treatment option if you have unstable angina or if lifestyle changes and medications don't effectively treat your chronic, stable angina. Coronary Artery Bypass Surgery – A vein or artery from somewhere else in your body is used to bypass a blocked or narrowed heart artery. It increases blood flow to the heart and reduces or eliminates angina. It's a treatment option for both unstable angina as well as stable angina and CAD that has not responded to other treatments. NURSING MANAGEMENT Relieving pain (angina) – Parameters of scaling; take vitals signs and monitor progression. Maintain cardiac output by monitoring patient’s response to drug therapy, take BP and monitor The pathophysiology of heart failure. A decrease in cardiac for changes. Institute ECG monitoring as output activates multiple neurohormonal mechanisms that directed, evaluate for development of heart ultimately result in the signs and symptoms of heart failure. failure. LEFT SIDED HEART FAILURE Decrease anxiety by explaining all procedures Left ventricular damage causes blood to back done to patient and family members, up through the left atrium and into the encourage patient and significant others to pulmonary veins. verbalize fears and concerns, explain the Increased pressure causes transudation into need of anxiety reduction measures to help the interstitial tissues of the lungs with resultant alleviate the anginal pain. Discuss measures to pulmonary congestion. be used in the event of an anginal episode. CAUSED BY: Left ventricular damage (MI, CAD) HEART FAILURE Hypertension, aortic valve disease (AI, AS) Inability of the heart to pump an adequate Mitral stenosis, cardiomyopathy supply of blood to meet the metabolic needs of ASSESSMENT FINDINGS the body; end stage complication of Easy fatigability S3 gallop pulmonary, systemic and cardiac disorders. Dyspnea on exertion Tachycardia PND Tachypnea @chadrayg 13 MEDSURG 3 - LEC 1ST SEMESTER | Disorders of the Cardio-Pulmonary System Orthopnea Rales NURSING INTERVENTIONS Cough Wheezing Monitor respiratory status and provide Nocturia Pleural effusion adequate ventilation (when CHF progresses to Confusion pulmonary edema). DIAGNOSTIC TEST Provide physical and emotional rest. ECG Cardiac Increase cardiac output. Chest x-ray catheterization Reduce/eliminate edema. (cardiomegaly, Decreasing PO2 Provide client teaching and discharge pleural effusion) Increasing PCO2 planning. Echocardiography RIGHT SIDED HEART FAILURE BUERGER’S DISEASE Weakened RV is unable to pump blood into the (THROMBOANGIITIS OBLITERANS) pulmonary system; systemic venous congestion Characterized by recurring inflammation of occurs as pressure builds up. the intermediate and small arteries and veins CAUSED BY: of the lower and upper extremities. Left sided heart failure Rare disease of blood vessels in your arms, RV infarction legs, fingers, and toes. Atherosclerotic heart disease Inflammation in your blood vessels makes it COPD, pulmonic stenosis, pulmonary embolism hard for your blood to flow through them. ASSESSMENT FINDINGS Blood clots can form, which create obstacles Easy fatigability Elevated jugular inside your blood vessels. Lower extremity venous pressure SYMPTOMS swelling Hepatomegaly Early signs include severe pain in your legs Early satiety Ascites and arms. This pain happens when your body RUQ discomfort Lower extremity is resting. edema Hand or foot pain (burning or tingling feeling). DIAGNOSTIC TESTS Sores on toes. Chest X-ray – Reveals cardiac hypertrophy. RISK FACTORS Echocardiography – Indicates increased size Smoking cigarettes. of cardiac chambers. Chewing tobacco. Elevated CVP, decreased PO2, increased Being male. ALT(SGPT). Being aged 20-45. MEDICAL MANAGEMENT DIAGNOSTIC FINDINGS (R/L SIDED FAILURE): No test can confirm. Determination and elimination/control of Blood tests rule out conditions such as underlying cause. scleroderma, lupus, blood-clotting disorders, Drug Therapy and diabetes. Diuretics: Furosemide, Spironolactone Diagnostic Test: Dilators: ACE inhibitors (lisinopril [Prinivil, Allen’s Test Zestril]), nitrates Ankle-Brachial Index (ABI) Digitalis: digoxin (antidote for toxicity: Additional tests rule out other conditions. Digibind) MEDICAL MANAGEMENT Diet: low salt, low cholesterol There is no treatment that can cure Buerger’s * If medical therapies unsuccessful, mechanical diseases, but the first and most important is assist devices (intra-aortic balloon pump), stop using tobacco. cardiac transplantation or mechanical hearts may be employed. @chadrayg 14 MEDSURG 3 - LEC 1ST SEMESTER | Disorders of the Cardio-Pulmonary System DRUG THERAPY SYMPTOMS Vasodilators – Papaverine, Isoxsuprine Hcl Cold fingers/toes. (Vasodilan), Nylidrin Hcl (Arlidin), nicotinyl Areas of skin that turn from white to blue. alcohol (Roniacol), cyclandelate PREDISPOSING FACTORS (Cyclospasmol), tolazoline Hcl (priscoline) to Collagen diseases (SLE, RA). improve arterial circulation; effectiveness Trauma (from typing, playing piano). questionable. COMPLICATIONS Analgesics to relieve ischemic pain. May lead to gangrene or amputations if in Anticoagulants to prevent thrombus formation. severe and prolonged exposure – This is Lipid Reducing Drug – Cholestyramine, RARE! colestipol Hcl, dextrothyroxine sodium, PREVENTION clofibrate, gemfibrozil (Lopid), niacin, Bundle up outdoors. lovastatin (Mevacor), and atorvastatin. During cold, use hat, scarf, socks and boots NURSING INTERVENTIONS and 2 sets of mittens or gloves. Compressing your arm and legs intermittently Thermal underwear might help. can increase blood flow to them. Wear earmuff and a facemask. Prepare client for surgery. Warm your car. Provide client teaching and discharge Take care indoors, wear socks. planning. Drug regimen, avoidance of trauma to the MEDICAL MANAGEMENT affected extremity, need to maintain Vasodilators warmth especially during cold weathers, Catecholamine-Depleting antihypertensive importance of stopping smoking. Drugs (reserpine, guanethidine monosulfate). RAYNAUD’S PHENOMENON VENOUS THROMBUS Causes small arteries that supply blood flow to Phlebitis – An inflammation in the wall of a the skin to narrow in response to cold or vein. stress. Superficial Thrombophlebitis (ST) – Clot forms TWO FORMS: in a vein secondary to phlebitis or because of Primary or Idiopathic Raynaud’s (Raynaud’s partial vein obstruction. Disease) – Occurs in the absence of an Phlebothrombosis – Formation of a thrombus underlying disease. or thrombi in a vein. Secondary Raynaud’s (Raynaud’s Deep Vein Thrombosis (DVT) – Thrombus Syndrome) – Occurs in association with an formation in deep veins rather than superficial underlying disease, usually a connective usually in the thigh or calf, but sometimes in tissue disorder, such as systemic lupus the arm where a common complication is erythematosus, rheumatoid arthritis, or Pulmonary Embolism. scleroderma; trauma; or obstructive arterial Pulmonary Embolism – Comes from DVT, lesions. not superficial; due to return of venous Affected body parts, usually fingers and toes, flow. might turn white, then blue. RISK FACTORS The affected areas may feel cold and numb Malignancy, previous history of venous until blood flow improves, usually after insufficiency, conditions causing prolonged warming up. bed rest, leg trauma, general surgery, obesity, Decreased blood flow to your fingers and toes. and smoking. Most common in women between 16-40 years of age, and it occurs more frequently in cold climates and during the winter. @chadrayg 15 MEDSURG 3 - LEC 1ST SEMESTER | Disorders of the Cardio-Pulmonary System CLINICAL MANIFESTATIONS VARICOSE VEINS (VARICOSITIES) DVT may occur asymptomatically or may Abnormally dilated, tortuous, superficial veins produce severe pain, fever, chills, malaise, caused by incompetent venous valves. swelling, and cyanosis of the affected leg. Primary varicose veins are bilateral dilatation ST produces visible and palpable signs such and elongation of saphenous veins. as heat, pain, swelling, erythema, tenderness, Secondary varicose veins result from and induration of the infected leg. obstruction of deep veins. DIAGNOSTIC EVALUATION Telangectasias (spider veins) are dilated Venous Duplex UTZ – Visualization of the superficial capillaries, arterioles and venioles. thrombus; non-invasive. They may be cosmetically unattractive but do Venography – IV injection of a radio-contrast not pose a threat to circulation. agent. The vascular tree is visualized and Occurs in the lower extremities, the saphenous obstruction is identified. veins, or the lower trunk, but it can occur Coagulation Profiles – APTT, PT/INR, elsewhere in the body, such as the esophagus circulating fibrin, monometer complexes, (e.g., esophageal varices) when flow or fibrinopeptide, serum fibrin, protein levels to pressure is abnormally high. detect intravascular coagulation. PREDISPOSING FACTORS MEDICAL MANAGEMENT Hereditary weakness of vein wall or valves. ANTICOAGULATION Long-standing distention of veins brought Heparin, followed by 3-6 months of oral about by obesity. anticoagulant therapy. Pregnancy or prolonged standing. Heparin and enoxaparin may also be given Old age due to loss of tissue elasticity. SQ as prophylaxis for the prevention of DVT. CLINICAL MANIFESTATIONS THROMBOLYTIC THERAPY Disfigurement due to large, tortuous leg veins, Tissue Plasminogen Activator or Streptokinase Easy leg fatigue. to dissolve clots within 24 hours. Cramps in leg. NON-PHARMACOLOGIC THERAPIES Heavy feeling. CBR, elevation of affected extremity, Increased pain during menstruation. compression, dry heat, and moist heat. Nocturnal muscle cramps. SURGICAL MANAGEMENT DIAGNOSTIC EVALUATION Thrombectomy Walking Tourniquet Test – Tourniquet is NURSING MANAGEMENT fastened on lower extremities and patient is Relieve pain by elevating legs as ordered to directed to walk for 2 minutes. promote venous drainage and reduce swelling. Photoplethysmography – Observe venous flow Prevent hazards related to immobility, prevent hemodynamics, non-invasive. pressure ulcers that may occur, utilize passive Doppler UTZ – Can accurately detect rapidly ROM exercises. the presence of venous reflux in superficial Encourage adequate fluid intake. and deep veins. Be alert for signs of PE. NURSING MANAGEMENT Discourage crossing of legs and long periods Instruct patient to: of sitting because compression of vessels can Avoid activities that cause venous stasis. restrict blood flow. Control excessive weight gain. Wear firm elastic support as prescribed from toe to thigh when in upright position. Elevate foot of bed 15-20 cm for night sleeping. Avoid injuring legs. @chadrayg 16 MEDSURG 3 - LEC 1ST SEMESTER | Disorders of the Cardio-Pulmonary System Report signs such as sensory loss, calf pain, MYOCARDITIS or fever to the health care provider. Affects muscle that makes your heart pump. Avoid dangling legs. An acute or chronic inflammation of the myocardium as a result of pericarditis, INFLAMMATORY DISEASES OF THE systemic infection or allergic response. HEART Results from an infectious source, be it viral TYPES OF HEART INFLAMMATION (e.g., coxsackieviruses A and B, human ENDOCARDITIS immune deficiency virus, influenza A), bacterial, rickettsial, fungal, parasitic, metazoal, Affects the lining in the heart chambers your protozoal (e.g., Chagas disease), or spirochetal. blood goes through and valves that control SYMPTOMS blood flow from one chamber to another. Swelling of the legs. Inflammation of the endocardium; platelets Heart palpitations. and fibrin deposit on the mitral and/or aortic valves causing deformity, insufficiency or Extreme tiredness. stenosis. IMPLEMENTATION Caused by bacterial infection: Assist client to assume a position of comfort. Commonly Staphylococcus aureus, Administer analgesics, salicylates, NSAIDS. Staphylococcus viridans, B hemolytic Administer O2, provide adequate rest streptococcus, and gonococcus. periods. PRECIPITATING FACTORS Limit activities to decrease workload of RHD, open heart surgery, GU/OB Gyn surgery, heart. dental extractions. Treat underlying cause. SYMPTOMS Administer medications as ordered: antibiotics, diuretics, ACE inhibitors, and Pain in your belly. digitalis. Hematuria due to renal infarction. Monitor complications: thrombus, heart Night sweats. failure, and cardiomyopathy. MEDICAL MANAGEMENT PERICARDITIS Drug Therapy: Affects the sac around the outside of your Antibiotics specific to sensitivity or organism heart. cultured An inflammation of the visceral and parietal PenG and streptomycin if organism not pericardium. known. Antipyretics. Caused by bacterial, viral, or fungal infection; collagen diseases; trauma; acute MI, Cardiac surgery to replace valve. neoplasms, uremia, radiation, drugs NURSING INTERVENTIONS (procainamide, hydralazine, Doxorubicin HCL) Antibiotics as ordered. SYMPTOMS Control temperature. Tachycardia. Assess for vascular complications and Chest pain that gets better when you sit-up and pulmonary embolism. lean forward. Provide client teaching and discharge MEDICAL MANAGEMENT planning. Determination and elimination/control of Types of procedures, antibiotic therapy. underlying cause. Signs and symptoms to report: persistent fever, fatigue, chills, anorexia, joint pains Drug Therapy: Avoidance of individuals with known Medication for pain relief. infections. Corticosteroids, *salicylates (aspirin), indomethacin, to reduce inflammation @chadrayg 17 MEDSURG 3 - LEC 1ST SEMESTER | Disorders of the Cardio-Pulmonary System Specific antibiotic therapy against the ARRHYTHMIAS causative organism may be indicated. Disorder of the formation or conduction (or NURSING INTERVENTIONS both) of the electrical impulse within the heart. Ensure comfort, bed rest with semi- or high These disorders can cause disturbances of the Fowler’s position. heart rate, the heart rhythm, or both. Monitor hemodynamic parameters. May initially be evidenced by the Administer medications as ordered and hemodynamic effect they cause (e.g., a monitor effects. change in conduction may change the Provide client teaching and discharge pumping action of the heart and cause planning. decreased blood pressure). Signs and symptoms of pericarditis Arrhythmias are diagnosed by analyzing the indicative of recurrence (chest pain electrocardiographic (ECG) waveform. intensified by lying down and relieved Arrhythmias are named according to the site when sitting up. of origin of the impulse and the mechanism of Medication regimen. formation or conduction involved. COMMON SYMPTOMS OF ALL 3 TYPES Chest pain. NORMAL ELECTRICAL CONDUCTION Shortness of breathing. Fever. WHAT CAUSES HEART INFLAMMATION? Usually from viruses or bacteria. Cause of most cases of heart inflammation. Normal pericardial fluid amount: 30 ml TESTS TO DIAGNOSE HEART INFLAMMATION Rule out a heart attack. Look for fluid around your heart. Look at how well your heart is functioning and see if there’s abnormal function. Tests include: Cardiac Computed Tomography (CT) Electrocardiogram (EKG) Echocardiogram Relationship of ECG complex, lead system, and electrical Cardiac MRI impulse. The heart conducts electrical activity, which the ECG measures and shows. The configurations of electrical activity Positron Emission Tomography (PET Scan) displayed on the ECG vary depending on the lead (or view) of – Tumors and progression. the ECG and on the rhythm of the heart. Therefore, the MANAGEMENT AND TREATMENT configuration of a normal rhythm tracing from lead I will differ from the configuration of a normal rhythm tracing from Corticosteroid lead II, lead II will differ from lead III, and so on. The same is Antibiotics true for abnormal rhythms and cardiac disorders. To make an accurate assessment of the heart’s electrical activity or to Antifungal drugs identify where, when, and what abnormalities occur, the ECG Anti-inflammatory drugs needs to be evaluated from every lead, not just from lead II. Heart failure medicine Here the different areas of electrical activity are identified by color. RA, right arm; LA, left arm; SA, sinoatrial; AV, Blood thinners atrioventricular; LL, left leg. HOW TO REDUCE RISK? The electrical impulse that stimulates and Don’t drink too much alcohol. paces the cardiac muscle normally originates Don’t use recreational drugs. in the SA node, an area located near the Take good care of your teeth. superior vena cava in the right atrium. Keep your skin clean to prevent infection. Usually, the electrical impulse occurs at a rate of 60-100 times a minute in the adult. @chadrayg 18 MEDSURG 3 - LEC 1ST SEMESTER | Disorders of the Cardio-Pulmonary System Conduction – The electrical impulse quickly Electrodes come in various shapes and sizes, travels from the sinus node through the atria to but they all have two components: the atrioventricular (AV) node. An adhesive substance that attaches to the The structure of the AV node slows the skin to secure the electrode in place. electrical impulse, giving the atria time to A substance that reduces the skin’s electrical contract and fill the ventricles with blood. impedance and promotes detection of the This part of atrial contraction is frequently electrical current. referred to as the “atrial kick“ and accounts The number and placement of the electrodes for nearly one third of the volume ejected depend on the type of ECG needed. during ventricular contraction. Most continuous monitors use 2-5 electrodes, The electrical impulse then travels very quickly usually placed on the limbs and the chest. through the bundle of His to the right and left These electrodes create an imaginary line, bundle branches and the Purkinje fibers, called a lead, that serves as a reference located in the ventricular muscle. point from which the electrical activity is Depolarization – Electrical stimulation. viewed. Systole – Mechanical contraction. A lead is like an eye of a camera: It has a Repolarization – Electrical relaxation. narrow peripheral field of vision, looking Diastole – Mechanical relaxation. only at the electrical activity directly in front INFLUENCES ON HEART RATE AND of it. CONTRACTILITY Therefore, the ECG waveforms that appear on the paper or cardiac monitor represent the The heart rate is influenced by the autonomic electrical current in relation to the lead. nervous system, which consists of sympathetic and parasympathetic fibers. ELECTRODE PLACEMENT Sympathetic nerve fibers (also referred to as adrenergic fibers) are attached to the heart and arteries as well as several other areas in the body. Stimulation of the sympathetic system increases heart rate (positive chronotropy), conduction through the AV node (positive dromotropy), and the force of myocardial contraction (positive inotropy). Parasympathetic nerve fibers are also attached to the heart and arteries. Parasympathetic stimulation reduces the Electrode placement used in continuous electrocardiographic heart rate (negative chronotropy), AV monitoring for three-lead system, placement on RA, LA, and LL; four-lead system, placement on RA, LA, RL, and LL; five-lead conduction (negative dromotropy), and the system, placement on RA, LA, RL, LL, and V1. force of atrial myocardial contraction. ELECTROCARDIOGRAM (ECG/EKG) Electrical impulse that travels through the heart can be viewed by means of electrocardiography, the end product of which is an ECG. Each phase of the cardiac cycle is reflected by specific waveforms on the screen of a cardiac monitor or on a strip of ECG graph paper. An ECG is obtained by slightly abrading the skin with a clean dry gauze pad and placing electrodes on the body at specific areas. @chadrayg 19 MEDSURG 3 - LEC 1ST SEMESTER | Disorders of the Cardio-Pulmonary System OBTAINING AN ELECTROCARDIOGRAM tape, which is later viewed and analyzed with a scanner. A patient may undergo an electrophysiology (EP) study in which electrodes are placed inside the heart in order to obtain an intracardiac ECG. For a standard 12-lead ECG, 10 electrodes (6 on the chest and 4 on the limbs) are placed on the body. These limb electrodes provide the first 6 leads: leads I, II, III, aVR, aVL, and aVF. The 6 chest electrodes are applied to the chest at very specific areas. The chest electrodes provide the V or precordial leads, V1 through V6. To locate the fourth intercostal space and the placement of V1, the sternal angle and then the sternal notch, which is about 1 or 2 inches below the sternal angle, are located. When the fingers are moved to the patient’s immediate right, the second rib can be palpated. The second intercostal space is the indentation felt just below the second rib. A standard 12-lead ECG reflects the electrical ECG electrode placement. The standard left precordial leads are: activity primarily in the left ventricle. V1–fourth intercostal space, right sternal border; Placement of additional electrodes for other V2–fourth intercostal space, left sternal border; leads may be needed to obtain more complete V3–diagonally between V2 and V4; V4–fifth intercostal space, left midclavicular line; information. V5–same level as V4, anterior axillary line; E.g., in patients with suspected right-sided V6 (not illustrated) –same level as V4 and V5, midaxillary line. heart damage, right-sided precordial leads The right precordial leads, placed across the right side of the are required to evaluate the right ventricle. chest, are the mirror opposite of the left leads. RA, right arm; LA, left arm; RL, right leg; LL, left leg. INTERPRETING THE ELECTROCARDIOGRAM Electrodes are attached to cable wires, which are connected to one of the following: An ECG machine placed at the patient’s side for an immediate recording (standard 12- lead ECG). A cardiac monitor at the patient’s bedside for continuous reading; this kind of monitoring, usually called hardwire monitoring, is used in intensive care units. A small box that the patient carries that continuously transmits the ECG information by radiowaves to a central monitor located ECG graph and commonly measured components. elsewhere (called telemetry). Each large box represents 0.20 seconds on the horizontal axis A small, lightweight tape recorder-like and 5 mm or 0.5 millivolt on the vertical axis. Each small box represents 0.04 seconds on the horizontal axis machine (called ambulatory ECG monitoring and 1 mm or 0.1 millivolt on the vertical axis. or a Holter monitor) that the patient wears PR interval is measured from the beginning of the P wave to and that continuously records the ECG on a the beginning of the QRS complex; @chadrayg 20 MEDSURG 3 - LEC 1ST SEMESTER | Disorders of the Cardio-Pulmonary System QRS complex is measured from the beginning of the Q wave to U Wave – Thought to represent repolarization the end of the S wave; QT interval is measured from the beginning of the Q wave to of the Purkinje fibers; although this wave is the end of the T wave; rare, it sometimes appears in patients with TP interval is measured from the end of the T wave to the hypokalemia (low potassium levels), beginning of the next P wave. hypertension, or heart disease. The ECG waveform reflects the function of the If present, the U wave follows the T wave heart’s conduction system, which normally and is usually smaller than the P wave. initiates and conducts the electrical activity, in If larger in amplitude, it may be mistaken relation to the lead. for an extra P wave. ECG waveforms are printed on graph paper PR Interval – Measured from the beginning of that is divided by light and dark vertical and the P wave to the beginning of the QRS horizontal lines at standard intervals. complex and represents the time needed for Time and rate are measured on the sinus node stimulation, atrial depolarization, horizontal axis of the graph, and amplitude and conduction through the AV node before or voltage is measured on the vertical axis. ventricular depolarization. When an ECG waveform moves toward the top In adults, the PR interval normally ranges of the paper, it is called a positive deflection. from 0.12-0.20 seconds in duration. When it moves toward the bottom of the paper, ST Segment – Represents early ventricular it is called a negative deflection. repolarization, lasts from the end of the QRS WAVES, COMPLEXES, AND INTERVALS complex to the beginning of the T wave. P Wave – Electrical impulse starting in the The beginning of the ST segment is usually sinus node and spreading through the atria. identified by a change in the thickness or Represents atrial depolarization. angle of the terminal portion of the QRS It is normally 2.5 mm or less in height and complex. 0.11 seconds or less in duration. The end of the ST segment may be more QRS Complex – Represents ventricular difficult to identify because it merges into depolarization. the T wave. Q Wave – Normally less than 0.04 seconds The ST segment is normally isoelectric. in duration and less than 25% of the R- It is analyzed to identify whether it is above wave amplitude. or below the isoelectric line, which may be, R Wave – First positive deflection after the P among other signs and symptoms, a sign of wave cardiac ischemia. S Wave – First negative deflection after the QT Interval – Represents the total time for R wave. ventricular depolarization and repolarization. When a wave is less than 5 mm in height, Measured from the beginning of the QRS small letters (q, r, s) are used; when a wave complex to the end of the T wave. is taller than 5 mm, capital letters (Q, R, S) Varies with heart rate, gender, and age; are used to label the waves. therefore, the measured interval may be The QRS complex is normally less than 0.12 corrected (QTc) for these variables through seconds in duration. specific calculations. T Wave – Represents ventricular repolarization Usually 0.32-0.40 seconds in duration if the (when the cells regain a negative charge; also heart rate is 65-95 bpm. called the resting state). Many medications commonly given in the It follows the QRS complex and is usually hospital can cause prolongation of the QT the same direction (deflection) as the QRS interval (QTc), placing the patient at risk for complex. a lethal ventricular arrhythmia called Atrial repolarization also occurs but is not torsades de pointes. visible on the ECG because it occurs at the PP Interval – Measured from the beginning of same time as ventricular depolarization (i.e., one P wave to the beginning of the next P the QRS). wave. Used to determine atrial rate and rhythm. @chadrayg 21 MEDSURG 3 - LEC 1ST SEMESTER | Disorders of the Cardio-Pulmonary System RR Interval – Measured from one QRS o E.g., There are approximately 7 intervals complex to the next QRS complex. in 6 seconds. Used to determine ventricular rate and Rate: 7 x 10 = 70 bpm rhythm. ANALYZING THE ELECTROCARDIOGRAM DETERMINING HEART RATE FROM THE RHYTHM STRIP ELECTROCARDIOGRAM INTERPRETING DYSRHYTHMIAS: SYSTEMATIC ANALYSIS OF THE ELECTROCARDIOGRAM When examining an ECG rhythm strip to learn more about a patient's dysrhythmia: Determine the ventricular rate. Determine the ventricular rhythm. Determine QRS duration. (A) Ventricular and atrial heart rate determination with a Determine whether the QRS duration is regular rhythm: 1500 divided by the number of small boxes between two P waves (atrial rate) or between two R waves consistent throughout the strip. If not, (ventricular rate). In this example, there are 25 small boxes identify other duration. between both the R waves and the P waves, so the heart rate is Identify QRS shape; if not consistent, then 60 beats per minute. (B) Heart rate determination if the rhythm is irregular. There identify other shapes. are approximately seven RR intervals in 6 seconds, so there are Identify P waves; is there a P in front of about 70 RR intervals in 60 seconds (7 x 70). The ventricular every QRS? heart rate is 70 beats per minute. Identify P-wave shape; identify whether it is 1-minute strip – Contains 300 large boxes or consistent or not. 1500 small boxes. Determine the atrial rate. Regular Rhythm (Easy and accurate method of Determine the atrial rhythm. determining heart rate). Determine each PR interval. Count the number of small boxes within an Determine if the PR intervals are consistent, RR interval and divide 1500 by that irregular but with a pattern to the number. irregularity, or just irregular. o Rate = 1500 / # of small boxes within RR Determine how many P waves for each interval QRS (P:QRS ratio). o E.g., There are 25 small boxes. In many cases, the nurse may use a Rate: 1500 / 25 = 60 bpm checklist and document the findings next to Count the number of large boxes within an the appropriate ECG criterion. RR interval and divide 300 by that number. o Rate = 300 / # of small boxes within RR interval OVERVIEW OF THE RESPIRATORY o E.g., There are 5 large boxes. SYSTEM Rate: 300 / 5 = 60 bpm Normal pleural fluid: 10-20 ml. Irregular Rhythm (Alternative but less accurate Normal oxygen of normal adult: 95-100%. method for estimating heart rate). COPD: until 90% (report if 89%) Count the number of RR intervals in 6 What happens in intrathoracic pressure during seconds and multiply that number by 10. inhalation? It will decrease. The top of the ECG paper is usually marked Gas exchange between blood and cell: at 3-second intervals, which is 15 large Respiration/