NCMB312 LEC PRELIM 2022 PDF

NCMB312 LECTURE: Exam Week 06 BSN 3RD YEAR 1ST SEMESTER PRELIM 2022...

NCMB312 LECTURE: Exam Week 06 BSN 3RD YEAR 1ST SEMESTER PRELIM 2022 Bachelor of Science in Nursing 3YA Professor: Dr. Potenciana A. Maroma Prelim Topics: Heart Valves Disturbance in Oxygenation - The four valves in the heart permit blood to flow in Coronary artery diseases only one direction. The valves, which are composed of Obstructive disorders thin leaflets of fibrous tissue, open and close in Restrictive disorders response to the movement of blood and pressure Hematologic Disorders - Peripheral Vascular changes within the chambers. There are two types of Disorders valves: atrioventricular and semilunar. Atrioventricular Valves ANTOMY OF THE HEART - The atrioventricular valves separate the atria from the Introduction ventricles. - The heart is a hollow, muscular organ located in the - The tricuspid valve, so named because it is composed of center of the thorax three cusps or leaflets, separates the right atrium from the - Mediastinum – where it occupies the space between the right ventricle. The mitral or bicuspid (two cusps) valve lies lungs and rests on the diaphragm. weighs approximately between the left atrium and the left ventricle 300 g (10.6 oz) Semilunar Valves - the weight and size of the heart are influenced by age, - The two semilunar valves are composed of three leaflets, gender, body weight, extent of physical exercise and which are shaped like half-moons. The valve between the conditioning, and heart disease. right ventricle and the pulmonary artery is called the - The heart pumps blood to the tissues, supplying them with pulmonic valve. The valve between the left ventricle and oxygen and other nutrients. the aorta is called the aortic valve. Three (3) layers of the Heart - The semilunar valves are closed during diastole. At this Endocardium – Inner layer consists of endothelial tissue point, the pressure in the pulmonary artery and aorta and lines the inside of the heart and valves. decreases, causing blood to flow back toward the Myocardium – middle layer made up of muscle fibers and semilunar valves. is responsible for the pumping action. Epicardium – The exterior layer of the heart CODE: E.M.E Coronary Arteries - These arteries originate from the aorta just above the aortic valve leaflets - The heart has high metabolic requirements, extracting approximately 70% to 80% of the oxygen delivered (other organs extract, arteries are perfused during diastole. - The artery rom the point of origin to the first major branch is called the left main coronary artery. Two branches arise from the left main coronary artery: the left anterior Heart Chambers descending artery, which courses down the anterior wall Diastole – relaxation phase of the heart, and the circumflex artery, which circles Systole – refers to the events in the heart during around to the lateral left wall of the heart. contraction of the two top chambers (atria) and two - The right side of the heart is supplied by the right coronary bottom chambers (ventricles). artery, which leads to the inferior wall of the heart. The Apical pulse – the pulsation created during normal posterior wall of the heart receives its blood supply by an ventricular contraction. Also called Point of Maximal additional branch from the right coronary artery called the Impulse (PMI) posterior descending artery J.A.K.E 1 of 57  NCMB 312 LECTURE: BSN 3RD YEAR 1ST SEMESTER PRELIM 2022 Myocardium Control of Heart Rate - The myocardium is the middle, muscular layer of the atrial - Cardiac output must be responsive to changes in the and ventricular walls. It is composed of specialized cells metabolic demands of the tissues. called myocytes, which form an interconnected network - For example, during exercise the total cardiac output may of muscle fibers. These fibers encircle the heart in a increase fourfold, to 20 L/min. This increase is normally figure-of eight pattern, forming a spiral from the base (top) accomplished by approximately doubling both the heart of the heart to the apex (bottom). During contraction, this rate and the stroke volume. muscular configuration facilitates a twisting and - Changes in heart rate are accomplished by reflex controls compressive movement of the heart that begins in the mediated by the autonomic nervous system, including its atria and moves to the ventricles. sympathetic and parasympathetic divisions. - The parasympathetic impulses, which travel to the heart Function of the Heart through the vagus nerve, can slow the cardiac rate, Cardiac Electrophysiology whereas sympathetic impulses increase it. - cardiac conduction system generates and transmits (Parasympathetic = PARA, unti unti mong pinapabagal. electrical impulses that stimulate contraction of the Sympathetic = urge to do the action) myocardium. Under normal circumstances, the - These effects on heart rate result from action on the SA conduction system first stimulates contraction of the atria node, to either decrease or increase its inherent rate. The and then the ventricles. The synchronization of the atrial balance between these two reflex control systems and ventricular events allows the ventricles to fill normally determines the heart rate. completely before ventricular ejection, thereby Baroreceptors maximizing cardiac output. Three physiologic - are specialized nerve cells located in the aortic arch and characteristics of two types of specialized electrical cells, in both right and left internal carotid arteries (at the point the nodal cells of bifurcation from the common carotid arteries). This is Purkinje cells, provide this synchronization: sensitive to changes in BP. - Automaticity: ability to initiate an electrical impulse Hypertension - Excitability: ability to respond to an electrical impulse - during this state cells increase their rate of discharge, - Conductivity: ability to transmit an electrical impulse transmitting impulses to the cerebral medulla. from one cell to another - This initiates parasympathetic activity and inhibits - Sinoatrial Node – primary pacemaker sympathetic response, lowering the heart rate and the - Atrioventricular Node – secondary pacemaker (kapag BP wala or hindi kayang mag function ng SA taga salo si AV Hypotension but cannot give the best function like SA, in short second - results in less baroreceptor stimulation, which option ganurn (awts beh saetttt djk HAHAHA) prompts a decrease in parasympathetic inhibitory Cardiac Cycle activity in the SA node, allowing for enhanced - It refers to the events that occur in the heart from one sympathetic activity. heartbeat to the next. - The resultant vasoconstriction and increased heart - During atrial and ventricular diastole, the heart chambers rate elevate the BP. are relaxed. As a result, the atrioventricular valves are Control of Stroke Volume open, whereas the semilunar valves are closed. Pressures - Stroke volume is primarily determined by three in all of the chambers are the lowest during diastole, factors: preload, afterload, and contractility. which facilitates ventricular filling. Preload - Venous blood returns to the right atrium from the superior - refers to the degree of stretch of the ventricular and inferior vena cava, then into the right ventricle. On the cardiac muscle fibers at the end of diastole. left side, oxygenated blood returns from the lungs via the commonly referred to as left ventricular end-diastolic four pulmonary veins into the left atrium and ventricle. pressure (LVEDP). Cardiac Output - Taandaan lang na ang PRELOAD nagbibigay or nagsu - refers to the amount of blood pumped by each ventricle supply ng blood sa chambers ng heart. Sa madlaing during a given period salita nagkakarga ka. Resting adult – 5 L/min Frank-Starling (or Starling) law - but varies greatly depending on the metabolic needs of - within limits, the greater the initial length or stretch of the body the cardiac muscle cells (sarcomeres), the greater the - Cardiac output is computed by multiplying the stroke degree of shortening that occurs. volume by the heart rate - Diuretics, venodilating agents (eg, nitrates), excessive Stroke volume loss of blood, or dehydration (excessive loss of body - is the amount of blood ejected per heartbeat. The average fluids from vomiting, diarrhea, or diaphoresis) reduce resting stroke volume is about 70 mL, and the heart rate is preload. 60 to 80 bpm. - Cardiac output can be affected by changes in either stroke volume or heart rate. J.A.K.E 2 of 57  NCMB 312 LECTURE: BSN 3RD YEAR 1ST SEMESTER PRELIM 2022 Afterload (worst pain) scale. Next, the nurse asks the patient to - resistance to ejection of blood from the ventricle, is describe the character or quality of the pain or the second determinant of stroke volume discomfort and its location. The nurse should keep the - systemic vascular resistance - resistance of the following important points in mind when assessing systemic BP to left ventricular ejection patients reporting chest pain or discomfort: - pulmonary vascular resistance - resistance of the 3) Past Health, Family, and Social History pulmonary BP to right ventricular ejection - What type of health concerns do you have? Are you - Pinagkaiba naman dito nag e excrete ka ng blood. able to identify any family history (Chart 26-2) or Meaning PALABAS sa heart. behaviors (risk factors) that put you at risk for this Contractility health condition? - refers to the force generated by the contracting - What are your risk factors for heart disease? What do myocardium. you do to stay healthy and take care of your heart? Ejection Fraction - How is your health? Have you noticed any changes - percentage of the end-diastolic blood volume that is from last year? From 5 years ago? ejected with each heartbeat - Do you have a cardiologist or primary health care - ejection fraction of the normal left ventricle is 55% to provider? How often do you go for checkups? 65%. - Do you use tobacco or consume alcohol? - right ventricular ejection fraction is rarely measured 4) Medications - Ito yung amount ng blood na nilalabas ng heart sa - Nurses collaborate with physicians and pharmacists to kada parts nya (aorta, ventricle, artery, veins) obtain a complete list of the patient’s medications Assessment including dose and frequency. - the key components of the cardiovascular assessment - Vitamins, herbals, and other over-the-counter remain the same, the assessment priorities vary medications are included on this list. During this aspect of according to the needs of the patient the health assessment, the nurse solicits answers to the - For example, an emergency department nurse performs a following questions to ensure that patients are safely and rapid and focused assessment of a patient in which acute effectively taking their medications. coronary syndrome (ACS), rupture of an atheromatous o Is the patient independent in taking medications? plaque in a diseased coronary artery, is suspected. o Are the medications taken as prescribed? - Diagnosis and treatment must be started within minutes o Does the patient know what side effects to report to of arrival to the emergency department. the prescriber? o Does the patient understand why the medication Physical Assessment regimen is important? 1) Common Symptoms o Are doses ever forgotten or skipped, or does the - Chest pain or discomfort (angina pectoris, ACS, patient ever decide to stop taking a medication? dysrhythmias, valvular heart disease) 5) Nutrition - Shortness of breath or dyspnea (ACS, cardiogenic - Dietary modifications, exercise, weight loss, and shock, HF, valvular heart disease) careful monitoring are important strategies for - Peripheral edema, weight gain, abdominal distention managing three major cardiovascular risk factors: due to enlarged spleen and liver or ascites (HF) hyperlipidemia, hypertension, and diabetes mellitus. - Palpitations (tachycardia from a variety of causes, Diets that are restricted in sodium, fat, cholesterol, or including ACS, caffeine or other stimulants, calories are commonly prescribed. electrolyte imbalances, stress, valvular heart disease, 6) Elimination ventricular aneurysms) - Typical bowel and bladder habits need to be identified. - Vital fatigue, sometimes referred to as vital Nocturia (awakening at night to urinate) is common in exhaustion (an early warning symptom of ACS, HF, or patients with HF. valvular heart disease, characterized by feeling - Fluid collected in gravity-dependent tissues unusually tired or fatigued, irritable, and dejected) (extremities) during the day (ie, edema) redistributes - Dizziness, syncope, or changes in level of into the circulatory system once the patient is consciousness (cardiogenic shock, cerebrovascular recumbent at night. disorders, dysrhythmias, hypotension, postural - The increased circulatory volume is excreted by the hypotension, vasovagal episode) kidneys (increased urine production).. 2) Chest Pain 7) Activity and Exercise - Chest pain and discomfort are common symptoms - As the nurse assesses the patient’s activity and that may be caused by a number of cardiac and exercise history, it is important to note that decreases noncardiac problems. When a patient experiences in activity tolerance are typically gradual and may go chest symptoms, the nurse asks questions that aid in unnoticed by differentiating among these sources of chest 8) Blood Pressure symptoms. During the assessment the patient is asked - Systemic arterial BP is the pressure exerted on the to identify the quantity of pain using a 0 (no pain) to 10 walls of the arteries during ventricular systole and J.A.K.E 3 of 57  NCMB 312 LECTURE: BSN 3RD YEAR 1ST SEMESTER PRELIM 2022 diastole. It is affected by factors such as cardiac intercostal spaces are located from this reference output; distention of the arteries; and the volume, point by palpating down the rib cage. velocity, and viscosity of the blood. b) Pulmonic area — second intercostal space to the - A normal BP in adults is considered a systolic BP less left of the sternu than 120 mm Hg over a diastolic BP less than 80 mm c) Erb’s point — third intercostal space to the left of Hg. the sternum - High blood pressure or hypertension is defined by d) Tricuspid area — lower half of the sternum along having a systolic blood pressure that is consistently the left parasternal area greater than 140 mm Hg or a diastolic BP greater than e) Mitral (apical) area — left fifth intercostal space at 90 mm Hg. the midclavicular line - Hypotension refers to an abnormally low systolic and f) Epigastric area — below the xiphoid process. diastolic blood pressure that can result in 13) Pulse Quality lightheadedness or fainting. - The quality, or amplitude, of the pulse can be 9) Pulse Pressure described as absent, diminished, normal, or bounding. - The difference between the systolic and the diastolic It should be assessed bilaterally. pressures is called the pulse pressure. 14) Heart Inspection and Palpation - It is a reflection of stroke volume, ejection velocity, - The heart is examined by inspection, palpation, and and systemic vascular resistance. Pulse pressure, auscultation of the chest wall. A systematic approach which normally is 30 to 40 mm Hg, indicates how well is used to examine the chest wall in the following six the patient maintains cardiac output. areas. - The pulse pressure increases in conditions that 15) Heart Auscultation elevate the stroke volume (anxiety, exercise, - A stethoscope is used to auscultate each of the bradycardia), reduce systemic vascular resistance locations identified in Figure 26-5, with the exception (fever), or reduce distensibility of the arteries of the epigastric area. (atherosclerosis, aging, hypertension). - The purpose of cardiac auscultation is to determine 10) Arterial Pulses heart rate and rhythm and evaluate heart sounds. The - Factors to be evaluated in examining the pulse are rate, apical area is auscultated for 1 minute to determine rhythm, quality, configuration of the pulse wave, and the apical pulse rate and the regularity of the quality of the arterial vessel. heartbeat. 11) Pulse Rate - Normal and abnormal heart sounds detected during - The normal pulse rate varies from a low of 50 bpm in auscultation are described in the following section. healthy, athletic young adults to rates well in excess of 16) Normal Heart Sounds 100 bpm after exercise or during times of excitement. - Normal heart sounds, referred to as S1 and S2, are - Anxiety frequently raises the pulse rate during the produced by closure of the AV valves and the physical examination. semilunar valves, respectively. - If the rate is higher than expected, it is appropriate to - The period between S1 and S2 corresponds with reassess it near the end of the physical examination, ventricular systole (Fig. 26-7). when the patient may be more relaxed. - When the heart rate is within the normal range, 12) Pulse Rhythm systole is much shorter than the period between S2 - The rhythm of the pulse is as important to assess as and S1 (diastole). However, as the heart rate the rate. Minor variations in regularity of the pulse are increases, diastole shortens. normal. - Normally, S1 and S2 are the only sounds heard during - The pulse rate may increase during inhalation and slow the cardiac cycle. during exhalation. S1—First Heart Sound. Tricuspid and mitral - This phenomenon, called sinus arrhythmia, occurs valve closure creates the first heart sound (S1). most commonly in children and young adults. - The word ―lub‖ is used to replicate its sound. - For the initial cardiac examination, or if the pulse S1 is usually heard the loudest at the apical rhythm is irregular, the heart rate should be counted by area. auscultating the apical pulse, located at the PMI, for a - The intensity of S1 from beat to beat due to full minute while simultaneously palpating the radial lack of synchronized atrial and ventricular pulse. contraction. a) Aortic area — second intercostal space to the S2—Second Heart Sound. Closure of the right of the sternum. To determine the correct pulmonic and aortic valves produces the second intercostal space, the nurse first finds the angle of heart sound (S2), commonly referred to as the Louis by locating the bony ridge near the top of ―dub‖ sound. The aortic component of S2 is the sternum, at the junction of the body and the heard the loudest over the aortic and pulmonic manubrium. From this angle, the second areas. intercostal space is located by sliding one finger to the left or right of the sternum. Subsequent J.A.K.E 4 of 57  NCMB 312 LECTURE: BSN 3RD YEAR 1ST SEMESTER PRELIM 2022 Abnormal Heart Sounds develop during systole the left sternal border to the pulmonic and aortic or diastole when structural or functional heart areas. problems - Alternatively, the examiner may begin the examination - These sounds are created by the vibration of at the aortic and pulmonic areas and progress the ventricle and surrounding structures as downward to the apex of the heart. blood meets resistance during ventricular - Initially, S1 is identified and evaluated with respect to filling. The term gallop evolved from the its intensity and splitting. cadence that is produced by the addition of a - Next, S2 is identified, and its intensity and any third or fourth heart sound, similar to the splitting are noted. sound of a galloping horse. - After concentrating on S1 and S2, the examiner listens - Gallop sounds are very low-frequency sounds for extra sounds in systole and then in diastole. and are heard with the bell of the stethoscope Sometimes it helps to ask the following questions: placed very lightly against the chest. Do I hear snapping or clicking sounds? S3—Third Heart Sound. An S3 occurs early in Do I hear any high-pitched blowing sounds? diastole during the period of rapid ventricular Is this sound in systole, or diastole, or both? filling. It is heard immediately after S2. ―Lub-dub Laboratory Tests DUB‖ (S3) is used to imitate the sound of the To assist in diagnosing the cause of cardiac-related signs beating heart with this gallop sound. It represents and symptoms a normal finding in children and adults up to 35 or To determine baseline values before initiating therapeutic 40 years of age. interventions S4—Fourth Heart Sound. S4 occurs late in To screen for modifiable CAD risk factors diastole. An S4 occurs just before S1 and is To ensure that therapeutic levels of medications (eg, generated during atrial contraction as blood antiarrhythmic agents and warfarin) are maintained forcefully enters a noncompliant ventricle. This resistance to blood flow is due to ventricular To evaluate the patient’s response to the therapeutic hypertrophy caused by hypertension, CAD, regimen (eg, effects of diuretics on serum potassium cardiomyopathies, aortic stenosis, and numerous levels) other conditions. ―LUB (S4) lub-dub‖ is used to To identify abnormalities that affect the prognosis of a imitate this gallop sound. During tachycardia, all patient with CVD four sounds combine into a loud sound, referred - Normal values for laboratory tests may vary to as a summation gallop. depending on the laboratory and the health care 17) Murmurs. Murmurs institution. This variation is due to the differences in - are created by turbulent flow of blood. The causes of equipment and methods of measurement across the turbulence may be a critically narrowed valve, a organizations. malfunctioning valve that allows regurgitant blood Cardiac Biomarker Analysis flow, a congenital defect of the ventricular wall, a Blood Chemistry, Hematology, and Coagulation Studies defect between the aorta and the pulmonary artery, or - Lipid Profile an increased flow of blood through a normal structure - Cholesterol Levels (eg, with fever, pregnancy, hyperthyroidism). - Triglycerides 18) Friction Rub. Brain (B-Type) Natriuretic Peptide - A harsh, grating sound that can be heard in both C-Reactive Protein systole and diastole is called a friction rub. Homocysteine - It is caused by abrasion of the inflamed pericardial Chest X-Ray and Fluoroscopy surfaces from pericarditis. Because a friction rub may Electrocardiography be confused with a murmur, care should be taken to - Traditional Echocardiography identify the sound and to distinguish it from murmurs - Transesophageal Echocardiography that may be heard in both systole and diastole. Magnetic Resonance Angiography - A pericardial friction rub can be heard best using the Cardiac Catheterization diaphragm of the stethoscope, with the patient sitting Angiography up and leaning forward. Continuous Electrocardiographic Monitoring Telemetry Auscultation Procedure Central Venous Pressure Monitoring - During auscultation, the patient remains supine and the examining room is as quiet as possible. - A stethoscope with both diaphragm and bell functions is necessary for accurate auscultation of the heart. - Using the diaphragm of the stethoscope, the examiner starts at the apical area and progresses upward along J.A.K.E 5 of 57  NCMB 312 LECTURE: BSN 3RD YEAR 1ST SEMESTER PRELIM 2022 DISTURBANCES IN OXYGENATION Discussed by: Dr. Potenciana A. Maroma Components involved in Oxygenation Heart Lungs Red Blood Cells Blood Vessels Anatomy and Physiology Review Heart - cone-shaped hollow muscular organ located in the mediastinum between the lungs - Pumps about 60ml/beat or 5L/min - Pericardium – protective covering of the heart 3 layers of cardiac muscle tissue: Epicardium – outermost layer Coronary Arteries Myocardium – middle layer Left Coronary Artery Endocardium – innermost layer - Left anterior descending – LV, Ventricular septum, chordae tendinae, papillary muscle, RV (lesser extent) - Circumflex coronary artery – LA, lateral & posterior surfaces of LV, portion of interventricular septum, SA node, AV node Right Coronary Artery - RA, RV, inferior portion of LV - Branching pattern of the coronary arteries varies considerably among individuals Electrophysiologic Properties of the Heart Automaticity - initiate an impulse spontaneously & repetitively Excitability (depolarization) - respond to a stimulus Chambers Conductivity - Right atrium (0-5 mmHg) - Transmit electrical impulses  SVC, IVC, Coronary sinus Contractility - Right Ventricle (25 mmHg) - Contract - Left atrium Refractoriness - Left ventricle - Inability to respond until repolarization Valves Conduction System of the Heart AV valves - Semilunar valves SA node (60-100 times/min) AV node (40-60 beats/min) Bundle of His R & L bundle branches Purkinje fibers (20-40 beats/min) J.A.K.E 6 of 57  NCMB 312 LECTURE: BSN 3RD YEAR 1ST SEMESTER PRELIM 2022  Sequence of events during cardiac cycle - Systole (contraction) – emptying - Diastole (relaxation) – filling Mechanical Properties of the Heart Cardiac Output - Heart rate o ANS,  endogenous cathecolamines o Parasympathetic NS (vagus nerve), beta blockers, Ca++-channel blockers - SV o Preload – volume of blood distending the ventricles at the end of diastole just before contraction o Afterload – resistance that the ventricles must overcome to eject blood o Contractility – contract Formula: Cardiac Output = HR x SV Assessment - History (focus: obtaining information about client’s risk factors & symptoms of cardiovascular disease) o Demographic data – age, gender, ethnic origin Vascular System o Family history & genetic risk Functions: o Personal history - Provide conduits for blood to travel from the heart to o Diet history nourish the various tissues of the body Socioeconomic status - Carries cellular waste to the excretory organs - History - Allows lymphatic flow to drain tissue fluid back into the Modifiable circulation - Cigarette smoking - Returns blood to the heart for recirculation - Physical inactivity - Obesity - Psychological variables - Chronic diseases J.A.K.E 7 of 57  NCMB 312 LECTURE: BSN 3RD YEAR 1ST SEMESTER PRELIM 2022 Non-modifiable risk factors Serum lipids - Age, gender, ethnic background, family history - Cholesterol (122-200mg/dl) Cigarette smoking – major risk factor for the devp’t of cad - TGL (40-160 or 35-135mg/dl) & pvd - HDL (45-50 or 55-60mg/dl) Obesity – strong indicator of cvd especially when - LDL (60-180mg/dl) abdominal obesity is present - HDL:LDL ratio (3:1) Physical Assessment Laboratory Tests II Major symptoms of cardiovascular disease (CVD) o C-Reactive Protein (