Jarvis CH 20 Heart and Neck Vessels PDF

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CH 20: HEART AND NECK VESSELS POSITION AND SURFACE LANDMARKS A. Cardiovascular system (CV): heart and blood vessels B. Precordium: area on ant. Chest overlying heart and great vessels C. Great vessels (GV)=major arteries and veins connected to heart D. Heart and GVs are b/t lungs in middle third of thoracic cage=mediastinum E. Heart: extends from 2nd-5th intercostal space and from R. border of sternum to left midclavicular line a. Right side is mostly anterior and left side is mainly posterior b. R. ventricle directly behind sternum c. L. ventricle lies behind R. ventricle and forms apex d. R. atrium lies to right and above R. ventricle e. L. atrium located post. w/ small portion showing ant. f. Top=base g. Bottom=apex–beats against wall during contraction forming apical pulse F. Blood vessels are arranged in 2 continuous loops a. Pulmonary circulation b. Systemic circulation G. GVs lie bunched above base of heart H. Superior and inferior vena cava return unoxygenated venous blood to R. side of heart I. Pulmonary artery leaves R. ventricle, bifurcates, and carries venous blood to lungs J. Pulmonary veins return oxygenated blood to L. side of heart and aorta carriers it to body

HEART WALL, CHAMBERS, AND VALVES A. Heart wall has many layers a. Pericardium: tough, fibrous, double walled sac surrounding and protecting heart i. Serous fluid ii. Myocardium: muscular wall of heart, does the pumping iii. Endocardium: thin layer of endothelial tissue that lines inner surface of heart chambers and valves B. R. side of heart pumps blood into lungs, L. side pumps blood into body C. Septum separates R. and L. side D. Atrium: reservoir for holding blood

E. Ventricle: pumping chamber F. Valves separate chambers and prevent backflow a. Open and close passively b. Four valves: i. Atrioventricular (AV) valves: separate atria and ventricles; open during diastole and close during systole 1. Tricuspid (R.) 2. Bicuspid/mitral (L.) ii. Semilunar valves: b/t ventricles and arteries; open during systole 1. Pulmonic (R.) 2. Aortic (L.) c. Anchored by chordae tendineae DIRECTION OF BLOOD FLOW A. Liver to RA thru inf. Vena cava a. Sup. Vena cava drain venous blood from head and upper extremities b. From RA venous blood travels thru tricuspid to RV B. From RV venous blood flows thru pulmonic valve to pulmonary artery a. Pulmonary artery delivers unoxygenated blood to lungs C. Lungs oxygenate blood a. Pulmonary veins return fresh blood to LA D. From LA arterial blood travels thru mitral valve to LV a. LV ejects blood thru aortic valve into aorta E. Aorta delivers oxygenated blood to body CARDIAC CYCLE A. Cardiac cycle: rhythmic movement of blood thru heart B. Two phases: a. Diastole: ventricles relax and fill with blood (2/3 of cardiac cycle) b. Systole: heart contraction C. Diastole: a. Ventricles relaxed; AV valves opened b. Pressure in atria higher=blood pours rapidly into ventricles (called early/protodiastolic filling) c. Towards end, atria contract and push remaining blood into ventricles– presystole/atrial systole or atrial kick D. Systole: a. Ventricle pressure is higher; AV valves shut=S1 b. Ventricles contract c. Aortic valves open and blood is ejected d. Semilunar valves close=S2

E. Diastole again: a. All valves closed, ventricles relax b. Atria fill with blood and pressure rises c. Mitral valves open, diastole beings again F. Events in right and left sides: a. Pressure in R. side is lower than L. because less energy is needed to pump into pulmonary circulation b. Events occur slightly later in R. side c. Two distinct components of heart sounds: i. In S1 mitral component (M1) closes before tricuspid component (T1) ii. In S2 aortic closure (A2) occurs slightly before pulmonic closure (P2) HEART SOUNDS A. Normal heart sounds: a. S1 occurs with closure of AV valves–loudest over apex; beginning of systole b. S2 occurs with closure of semilunar valves–loudest at base; end of systole c. Effect of respiration: i. MoRe to the Right heart, Less to the Left ii. During inspiration, intrathoracic pressure is decreased 1. Pushes more blood into vena cava, increasing venous return to R. side of heart, increasing R. ventricular stroke volume 2. Prolongs ventricular systole and delays pulmonic valve closure iii. On L. side, greater amount of blood is sequestered in lungs during inspiration 1. Momentarily decreases amount returned to left side of heart, decreasing left ventricular systole and allowing aortic valve to close earlier 2. Aortic valve closing before pulmonic creates split in S2 B. Extra heart sounds: a. Third heart sounds (S3): i. Occurs when ventricles are resistant to filling during early rapid filling phase (protodiastole) ii. Occurs immediately after S2 b. Fourth heart sound (S4): i. Occurs at end of diastole, at presystole, when ventricle is resistant to filling ii. Atria contract and push blood into noncompliant valve iii. Creates vibrations heard as S4 just before S1 C. Murmurs a. Turbulent blood flow and collision b. Gentle, blowing, swooshing sound heard on chest wall

c. Can result from: i. Velocity of blood increases (flow murmur) ii. Viscosity of blood decreases iii. Structural defects in valves or unusual openings in chambers D. Characteristics of sound a. All heart sounds are described by: i. Frequency (pitch) ii. Intensity (loudness) iii. Duration iv. Timing (systole or diastole) CONDUCTION A. Heart can contract by itself in response to electrical current conveyed by SA nodes B. PQRST: a. P Wave: depolarization of atria b. PR interval: from beginning of P wave to beginning of QRS complex c. QRS complex: depolarization of ventricles d. T wave: repolarization of ventricles PUMPING ABILITY A. Normally pumps b/t 4-6L of blood per minute B. CO=SVxHR C. Preload and afterload affect heart’s ability to increase CO D. Preload=volume–venous return that builds during diastole; force of stretch a. Frank-Starling law: greater the stretch, greater the contraction E. Afterload=pressure–opposing pressure ventricle must generate to open aortic valve against higher aortic pressure a. Resistance against which the ventricle must pump its blood b. Ventricular muscle tenses THE NECK MUSCLES A. CV assessment includes survey of vascular structures in neck–carotid artery and jugular veins a. These reflect efficiency of cardiac function B. Carotid artery pulse a. Carotid artery=central artery b. Timing closely coincides with ventricular systole c. Carotid artery: located in groove b/t trachea and sternomastoid muscle d. Note waveform C. Jugular venous pulse and pressure a. Jugular veins empty unoxygenated blood directly into superior vena cava

b. Give info about activity on right side of head c. Reflect filling pressure and volume changes d. 2 jugular veins are present in each side of neck i. Internal jugular: larger, deep, medial to sternomastoid muscle 1. Usually not visible ii. External jugular: more superficial, lies lateral to sternomastoid muscle, above clavicle e. Jugular venous pulse caused from backwash, a waveform moving backward caused by events upstream f. Jugular pulse has 5 components (see pic) i. Occur b/c of events in R. side of heart ii. A wave=atrial contraction iii. C wave=ventricular contraction iv. X descent=shows atrial relaxation when right ventricle contracts v. V wave=passive atrial filling vi. Y descent=reflects passive ventricular filling DEVELOPMENTAL COMPETENCE A. The Pregnant Woman a. CV system adapts to ensure adequate blood supply to uterus and placenta b. Blood volume increases 30-50%; most rapid expansion occurs in 2nd semester c. Increase in SV and CO and increased pulse rate by 10-20 beats/min d. Peaks in 3rd trimester e. Returns to baseline ~10 days postpartum f. Arterial BP decreases as result of peripheral vasodilation g. BP drops to lowest in 2nd trimester and rises after that B. Infants and Children a. Heart begins to beat at 3 weeks gestation b. Lungs nonfunctional but fetal circulation compensates c. Oxygenation takes place at placenta d. Oxygenated blood rerouted in 2 ways: i. About 2/3 is shunted through opening in atrial septum–foramen ovale–into L. side of heart, then thru aorta ii. Rest of oxygenated blood is pumped by R. side of heart out thru pulmonary artery, detoured thru ductus arteriosus to aorta e. R. and L. ventricles are equal in in weight and muscle wall thickness f. Forman ovale closes in 1st hour after birth g. Ductus arteriosus closes within 10-15 hours h. Hearts position in more horizontal i. Apex is higher–located at 4th intercostal space C. Aging Adult

a. Lifestyle modifies development of CV diseases and aging process D. Hemodynamic Changes with Aging a. Increase in systolic BP–isolated systolic hypertension i. Caused by thickening and stiffening of large arteries b. L. ventricular wall thickness increases–compensates for vascular stiffening c. Diastolic BP may decrease after 5th decade, systolic rises=increase in pulse rate d. No change in resting heart rate e. CO at rest not changed f. Decreased ability of heart to augment CO w/ exercise i. Shown by decreased maximum heart rate w/ exercise and diminished sympathetic response g. Noncardiac factors also cause decrease in maximum work performance w/ aging h. Dysrhythmias: presence increases with aging i. Ectopic beats are common ii. Tachydysrhythmias may not be tolerated well 1. Myocardium is thicker and less compliant and earlier diastolic filling is impaired at rest 2. May further compromise a vital organ i. Electrocardiograph: age relate changes to ECG occur as result of histologic changes in conduction system i. changes include: 1. prolonged P-R interval and prolonged Q-T interval, QRS is unchanged 2. L. axis deviation from age-related mild LV hypertrophy and fibrosis in L. bundle branch 3. Increased incidence of bundle branch block j. Incidence of CV disease (CVD) increases with age i. CVD=leading cause of death >65 ii. Health teaching is crucial treatment parameter CULTURE AND GENETICS A. CVD is most common underlying cause of death in the world B. Inherited DNA variation and lifestyle factors each contribute independently to development of major form of CVD–coronary artery disease (CAD) C. Adapting favorable lifestyle decreases risk of CAD D. Favorable lifestyle includes: a. No smoking b. No obesity c. Physical activity at least 1 per week d. Healthy diet E. High blood pressure

F. G. H. I.

a. Untreated hypertension causes direct damage to arterial system b. Hypertension contributes to CAD because it accelerates atherosclerosis Smoking a. Increases risk of CVD by increasing oxygen demand on heart Serum cholesterol Physical activity (PA) Sex and gender differences a. Leading cause of death in women is CVD b. Gender differences involve: ethnicity, culture, socioeconomic status c. Women delay seeking care for CVD because symptom cluster is different i. More likely to experience prodromal symptoms linked with fatigue 1. Discomfort in jaw/teeth, unusual fatigue, arm pain, shortness of breath ii. Providers less likely to take them seriously

OBJECTIVE DATA PREPARATION A. Sitting up for carotid arteries B. Supine for jugular veins and precordium with head and chest b/t 30-45º C. Stand on persons right side D. Room must be warm E. When performing regional CV assessment use this order: a. Pulse and BP b. Extremities c. Neck vessels d. Precordium NECK VESSELS A. Yields imp. info on cardiac function B. Avoid excessive pressure on carotid sinus area higher in neck C. Palpate gently D. Only one carotid at a time! E. Feel contour and amplitude of pulse F. Auscultate the carotid artery a. If symptoms of CVD, auscultate each carotid for presence of bruit b. Keep neck in neutral position c. Lightly apply bell at three levels: i. Angle of jaw ii. Midcervical area iii. Base of neck d. Ask person to hold breath briefly

G. Inspect the jugular venous pulse a. Can assess central nervous pressure (CVP) and judge hearts efficiency as a pump b. Stand on right side c. Can see top of external jugular vein distention overlying sternomastoid muscle or pulsation of internal in sternal notch d. Position supine 30-45º

THE PRECORDIUM A. Inspect the anterior chest a. Make sure lighting is good b. Pulsations: i. May or may not see apical pulse–occupies 4th-5th intercostal space B. Palpate the apical pulse a. Localize by using 1 finger pad b. “exhale then hold it” c. May need to roll person midway to left d. Felt best at end of expiration e. Note: i. Location–4th or 5th interspace, at or medial to midclavicular line ii. Size–1x2cm iii. Amplitude–short, gentle tap iv. Duration–short C. Palpate across precordium a. Use palmar aspect of four fingers, gently palpate apex, left sternal border, and base searching for pulsations b. If any present, note timing D. Auscultation a. Identify auscultatory areas i. Include 4 traditional valve “areas” ii. Sound radiates with direction of blood flow b. Valve areas are: i. Second right interspace–aortic valve ii. Second left interspace–pulmonic valve iii. Left lower sternal border–tricuspid valve iv. 5th interspace at left midclavicular line–mitral valve

c. Inch stethoscope in rough “Z”-pattern from base of heart to apex d. Use diaphragm and bell e. Make person aware that just because you listen longer doesn’t mean something is wrong f. Listen to one sound at a time g. Begin with diaphragm of SC and: i. Note rate and rhythm ii. S1 and S2 iii. Assess S1 and S2 separately iv. Listen for extra heart sounds v. Listen for murmurs h. Note rate and rhythm: i. Usually 50-90bpm ii. Sinus arrhythmia common in kids and young adults iii. If you notice irregularity, check for pulse deficit i. Identify S1 and S2 i. Lub=S1 ii. Dup=S2 iii. Guidelines to help: 1. S1 is louder at apex, S2 louder at base iv. S1 coincides with carotid v. S1 coincides with R wave on ECG monitor j. Focus on systole, then diastole, then any extra heart sounds i. Midsystolic click is common extra sound k. Listen for murmurs and describe: i. Timing–systole or diastole? Early, mid, or late? Obscures or muffles heart sound? ii. Loudness–intensity in terms of 6 grades 1. Grade1=barely audible 2. Grade 2=clearly audible, but faint 3. Grade 3=moderately audible 4. Grade 4=loud, palpable thrill

5. Grade 5=very loud 6. Grade 6=loudest iii. Pitch–high, medium, low? iv. Pattern–crescendo, decrescendo, diamond shape? v. Quality–musical, blowing, harsh, rumbling vi. Location vii. Radiation viii. Posture–innocent (no pathological cause) or functional (caused by increased blood flow to heart)? l. Change position–sit up, lean forward slightly, exhale m. Standing to squatting–screening measure to detect hypertrophic cardiomyopathy in children, young adults, and adolescents PROCEDURES FOR ADVANCED PRACTICE A. Estimate jugular venous pressure a. Use angle of louis and compare it with highest level of distended vein or venous pulsation b. Hold vertical ruler on sternal angle c. Align straightedge like T-square d. Read level of intersection of vertical ruler (normally 2cm or less above sternal angle) e. State persons position

B. Abdominaljugular test–use if you suspect heart failure or venous pressure is elevated a. Position supine b. Breathe quietly thru open mouth c. Hold right hand over midabdomen and watch level of jugular pulsation as you push with hand d. Exert firm sustained pressure for 10 seconds DEVELOPMENTAL COMPETENCIES A. Infants

a. Transition from fetal to pulmonic circulation occurs in immediate newborn period b. Assess CV system during 1st 24 hours and again in 2-3 days c. Note any extracardiac signs that may reflect heart status, liver size, and respiratory status d. Palpate apical pulse–4th intercostal e. Heart rate is best auscultated f. HR is 100-180bpm immediately after birth and stabilizes to 120-140 g. Expect sinus arrythmia h. Expect heart to be louder i. Murmurs are common B. Children a. Note any cardiac or extra cardiac signs that may indicate heart disease b. Note any bulge or heave in apical pulse c. Palpate apical pulse in 4th intercostal space to left of midclavicular line until age 4 i. At 4th interspace of midclavicular line from 4-6 years and 5th interspace to right of midclavicular line at age 7 d. Physiological S3 is common e. Venous hum is common f. Carotid bruit g. Innocent heart murmurs are common C. The Pregnant Woman a. HR increases and BP decreases b. Apical pulse higher c. Mild hyperemia in light-skinned women d. Exaggerated splitting of S1 is common as is increased loudness of S1 are common, e. Mammary souffle–continuous murmur from breast vasculature which occurs near term or when mother is lactating i. Caused by increased blood flow through the internal mammary artery D. Aging adult a. Gradual rise in SBP b. Orthostatic hypotension c. Avoid pressure in carotid sinus area d. Chest increases in anteroposterior diameter e. Occasional premature ectopic beats...