Pediatric Cardiology - PDF

Pediatric Cardiology  Fetal Circulation in fetal circulation pressure is higher on the right because pulmonary circulation resistance is higher (because lungs are collapsed) once baby is born that changes and then the left side is higher (because lungs open)  Neon...

Pediatric Cardiology  Fetal Circulation in fetal circulation pressure is higher on the right because pulmonary circulation resistance is higher (because lungs are collapsed) once baby is born that changes and then the left side is higher (because lungs open)  Neonates & Infants Heart & great vessels develop during first 3-8 weeks of gestation hard to hear resp sounds) Heart sounds in the neonate are higher pitched & of greater intensity than adult Neonates & infants are dependent on adequate HR & rhythm to maintain cardiac output because the can’t ↑ stroke volume Neonatal & infant myocardial muscle is less efficient & has fewer organized myocardial fibers, so it is very dependent on calcium, glucose & volume for adequate cardiac output. so youll see an increase in HR when they need more CO  Conduction System surgeries can interfere with AV nodes = arrythmias and heart blocks most surgical procedures take place in the AV node  Physiology Cardiac output- volume of blood ejected by heart in 1 minute Preload- volume of blood returning to the heart Afterload- resistance against which ventricles pump when ejecting blood Contractibility- ability of cardiac muscle to act as an efficient pump Adequate Systemic Profusion all of these things have to be in place for adequate systemic profusion; hr always the first thing to change to increase CO Appropriate heart rate Adequate circulating blood volume Low pulmonary vascular resistance Capillary permeability Tissue utilization of O2  Assessment of Cardiac Function History * mother’s health history infants born to a person with type one diabetes or lupus have an increase risk of congenitial heart defect; Infants born to someone who has PKU (metabolism disorder) they need to be on a special diet so they won't have a buildup of of fetal ketones in blood which leads to neurological devastation; diet is important * pregnancy because they can't breakdown amylin; PKU= DIET FOREVER assisted reproductive technology = increased heart defect we wanna know if they have had any infection rubella foot mouth disease (coxokee) Cox A: foot mouth and disease * birth history Cox B: encepholopathy; myocarditis (increased risk of heart disease) cytomeglovirus= if no antibodies and know apgar score; know birth weight; did they have myconium stool exposed during pregnancy's; risk of after birth or before; fetus who aspirate myconium in utero are at risk congenitial heart defect for pulmonary hypertension; were they full turm; ask about c-section; Herpes: Risk of congenitial heart defect was it difficult delivery; did the baby go to the nursery or NICU (concerns with the baby) prescription medication= need to change to * family health history something less toxic to the fetus ex: Phentanoin (Dylantin) is anticonvulsant you fam hx of congential heart disease increases need to change to something else; amphetamines; lithium; acutane (monthly pregnancy test) = all cause increased risk of congenitial heart defect you wanna ask about alcohol; cocaine use because of fetal alcohol syndrome = cong heart defect  Health History of Infant Feeding patterns Weight gain because these factors can be abnormal in infants with congenitial heart defects) Development Incidence of respiratory infections & breathing problems infants = periorbital Color changes edema first place is in the mouth (blue color when feeding or crying) children= peripheal edema Older children – exercise intolerance, edema, respiratory problems, chest pain, palpations, neurologic problems poorly in school = decrease oxygenation to the brain Recent infections or toxic exposures more asst with acquired heart disease Other health problems & medications  Physical Exam Vital Signs you wanna do a 4 extremity blood pressure to look for difference between upper and lower extremity if there is a difference it could be an indiciation of coarctation of the General inspection aorta = narrowing of aorta (strong extremity pulses and higher bp and lower extremity pulses and lower BP) check o2 sat performed after 24 hrs of life = one skin color sitting on lap of care giver lead on right hand (preductal and then either foot check loc (post ductal) if a greater diff of 2% difference it can comfort be a indicator of right to left shunting if present you all of this before touching have dexoxygenated blood going into the left side position of comfort of the heart and into systemic circulation. overall nutritional status Palpate point of maximum intensity and apical impulse 7yr 5th tells you how well left vent is working Presence of a thrill soft vibration of the heart = inducation of valve anomaly=turbulence  Physical Assessment ♦Quality & symmetry of pulses T check left to right and upper and lower ♦Warmth of extremities and capillary refill ♦Edema ♦Hepatic & splenic boarders check if its enlarged; if you have Right sided HF you'll have enlarged liver and spleen ♦Auscultate heart sounds - quality, intensity, rate & rhythm - presence of additional heart sounds ♦ Auscultate lung sounds advantagous sound; check for dimished breathe sounds murmur is a distinguished sound (swish) check where murmur can be heard best and when is it; is it systole or distole; after s1 or s2? does it change with position? how loud is it? 3rd and 4th intercostal; this place is good for to hear AV valve murmurs and diastolic murmurs that occur after S2  Heart Murmurs Distinct swishing sounds that occur in addition to normal heart sounds Record the following: 1. location – murmur heard best 2. time – when in S1 S2 cycle 3. intensity – relation to child’s position 4. loudness  Grading of Murmurs I Very faint, often not heard if child sits up II Usually readily heard, slightly louder than grade I: audible in all positions III Loud, but not accompanied by a thrill IV Loud, accompanied by a thrill V Loud enough to be heard with a a stethoscope barely touching the chest; accompanied by a thrill VI Loud enough to be heard with stethoscope not touching chest; accompanied by thrill most common murmur is a in children is a VST Hemodynamics Infants = PDA murmur which is a mechanical murmur Blood flows from area of higher pressure to low pressure & takes the path of least resistance can be hole thats between the Left and right venticle Pressure on right side less than left side Resistance in pulmonary artery ↓ than systemic circulation Pressure in pulmonary artery ↓than pressure in the aorta  Saturations Blood returning through great veins (SVC & IVC ) have lowest O2 saturations Blood returning from lungs to pulmonary veins is fully saturated. Aorta first supplies heart muscles through coronary arteries then supplies the brain. Normally saturated blood circulates separately from desaturated in some disorders this is mixed which is why you see cyanosis  SYSTOLE DIASTOLE  Hemodynamic Classifications Increased pulmonary blood flow Decreased pulmonary blood flow Obstruction to blood flow out of the heart Mixed blood flow  Incidence 5 – 8/1000 births CHD major cause of death in 1st year of life Most common is VSD Etiology of 90% is unknown  Defects with ↑ Pulmonary Blood Flow Atrial Septal Defect ( ASD ) * primum – lower end of septum * secundum – center of septum most common * sinus venus defect – junction of SVC & right atrium Left to right shunting Right Atrial & Ventricle enlargement CHF unusual due to shunting but it goes away after defect is corrected can wait until school age because it might close on its own; surgery is not often indicate cause hole can close in the cathlab. mortality of less than 1%  ASD Symptoms -may be asymptomatic -may develop CHF -murmur audible maybe a grade 2? Treatment this ok because the blood is oxygenated its more concerning if the blood is -patch deoxygenated to oxygenated (right to left) because it goes into systmic circulation -closure devices in CC  increase pulmonary blood flow Ventricular Septal Defect (VSD) Opening between right & left ventricle Membranous or muscular most time is membranous Frequently with other defects common with syndromes such as fetal alcohol syndrom 20 – 60 % close spontaneously during first year of life may wait till 1yr of life for surgery ↑in pulmonary blood flow ↑pressure in right ventricle→hypertrophy Eisenmenger syndrome may develop not common in US born children because of this pulmonary resistance this ends up causing occurs when VSD remains open for an extended amount of time an increase pressure in pulmonary artery and right blood from left ventricle goes into right ventricle and into the lungs ventricle; think about it = it makes it harder for the RV to and lungs dont like this = pulmonary hypertension = damage to muscle pump blood and then the the pressure becomes higher in walls of the pulmonary arterioles = hypertrophy of pulmonary arterioles = the right side than the left side causing deoxygenated increased resistance in blood vessels = increase pulmonary resistance blood going to the left side of the blood and out into because lungs are not used to this. systemic circulation causing CYANOSIS. ONLY IN CHILDREN WITH EISENMENGER SYNDROME  VSD only cyanosis with eisenmenger syndrome Symptoms - CHF common - murmur audible Treatment - small defects – purse string approach - large – patch - closure in CC low mortality if no comorbidities  Increase pulmonary AV Canal Incomplete closure of endocardial cushions Low ASD continuous with high VSD Defects in mitral & tricuspid valve Blood flow between all 4 chambers of the heart Most common defect in Down’s syndrome  look this up! AV Canal Symptoms * CHF 8* murmur audible O* mild cyanosis that ↑ with crying Treatment * patch closure of septal defects & reconstruction of valves Complications * heart block, CHF, MV regurgitation, arrhythmias, pulmonary hypertension open heart surgery; no cathlab can cause eisenmiger syndrome endocardial cushing surgery is near AV valve= AV valve can cause heartblock. all children will have pacing wires in place just incase they need to be connected to a pacemaker  Patent Ductus Arteriosis (PDA) Failure of PDA to close with in first weeks of life ↑ pulmonary blood flow Right ventricular hypertrophy Symptoms – may show signs of CHF, murmur Medical management – indomethacin Surgery – ligation, coil in CC low mortality rate; once PDA closes the child is ok PDA  Acyanotic Obstructive Defects increases afterload Coarctation of the Aorta * localized narrowing near insertion of Ductus Arteriosis * ↑pressure in head & upper extremities * ↓pressure in body & lower extremities blood flow to lower aorta through collateral circulatiion heart compensates with this disorder microvascular circulation in the capillaries to increase blood flow to the lower extremities  COA Symptoms blood to superior - ↑upper extremities BP - ↓lower extremities BP - bounding upper extremities pulses - weak pulses in lower extremities blood to - CHF in infants inferior - older children – headache, dizziness, leg pain because of decrease blood flow Treatment - resection of constricted section - stent to open it up  Aortic Stenosis Narrowing or stricture of aortic valve ↓cardiac output Left ventricular hypertrophy Pulmonary vascular congestion Types can have lung congestion because of back up of blood * valvular stenosis * subvalvular stenosis * supravalvular stenosis  Aortic Stenosis Symptoms - faint pulsespoor capillary time and cooler skin - hypotension - tachycardia - poor feeding - exercise intolerance - chest pain - dizziness with standing  Treatment Surgery – Ross procedure * aortic valve replaced with pulmonic valve, then pulmonic valve replaced with homograph valve. homograph valve doesnt get deteriorated as much in the pulmonic * done with valvular stenosis area because of the lower pressure! Balloon angioplasty in CC has to be replaced sooner; mechanical vales = risk for clots = coumadin for life  Obstructive Defects Pulmonic Stenosis Narrowing of entrance to pulmonary artery Right ventricular hypertrophy with ↓PBF Pulmonary atresia - total fusion If PS severe, CHF PDA partially compensates for obstruction Symptoms with severe PS foramen ovale opens causing desaturated blood going into systemic circulation = cyanosis * may be asymptomatic * mild cyanosis or CHF if severe * newborns – cyanotic because of foramen ovale? * murmur Treatment – balloon angioplasty in CC or surgical valvotomy  Right ventricular hypertrophy ↓ Right ventricular failure ↓ ↑Right atrial pressure ↓ Reopening of PFO ↓ Shunting of blood to left atrium ↓ Systemic cyanosis PS  Defects with ↓ Pulmonary Blood Flow Tetrology of Fallot ( TOF ) 4 defects 1. VSD 2. pulmonic stenosis 3. overriding aorta 4. right ventricular hypertrophy Depending on position of aorta, blood from both ventricles may be distributed systemically  TOF Symptoms - cyanosis cyanosis location of the aorta determines how much - TET spells Treatment - Palliative – Blalock- subvalvular PS its the tissue below the valve = S sits between left and right side instead of the left side ventricular hypertrophy Taussing shunt - Complete repair – close VSD, pericardial patch complete repair by first year of life until surgery they need to have more blood to the lungs  The tricuspid valve normally allows blood to flow from the right atrium (RA) to the right ventricle (RV). In tricuspid atresia, this valve is more severe completely absent, so blood can’t go from the RA to the RV. Tricuspid Atresia no tricuspid valve No communication from right atrium to right ventricle patent foramen ovale ASD or PFO necessary Complete mixing or oxygenated and deoxygenated blood PDA – allows blood flow to pulmonary artery for oxygenation VSD – blood flow to enter right ventricle ↓ pulmonary blood flow ASD or PFO is necessary: An Atrial Septal Defect (ASD) or Patent Foramen Ovale (PFO) acts as a "backup door" to allow blood to mix and flow. Deoxygenated blood (from RA) mixes with oxygenated blood (from LA), ensuring some oxygen delivery to the body. This mixing is not ideal but helps the baby survive. Complete mixing of oxygenated and deoxygenated blood: Because of the ASD or PFO, blood mixes completely in the left atrium (LA) or left ventricle (LV), resulting in low oxygen levels in blood going to the body. This causes cyanosis (bluish skin discoloration). PDA allows blood flow to the pulmonary artery: A Patent Ductus Arteriosus (PDA) is crucial. It allows blood from the aorta to flow back to the pulmonary artery, enabling some blood to reach the lungs for oxygenation. Without a PDA, there would be almost no blood going to the lungs, making this condition much worse. VSD (Ventricular Septal Defect): If there’s a Ventricular Septal Defect (VSD), some blood can flow into the small RV and then to the pulmonary artery. This further helps improve oxygenation by allowing more blood to reach the lungs. diagnosed in utero; prostoglandin E is given to keep PDA open to increase blood flow to the lungs TA PDA here to allow · blood flow from aorta to pulmonic artery Symptoms - cyanosis - tachycardia - dyspnea only way to get blood to the rest of the heart - clubbing is to create a hole Treatment - Prostoglandin E Surgery 1. Blalock-Taussing 2. Bidirectional Glenn 3. Modified Fontan until surgery 02 sats are in the 70's body has a hard time accomodating to the increase in oxygen after surgery all blood flow to the lungs is passive circulation w/ glenn and fontan = risk for clots!  Mixed Defects without any defects = incompatible with life Transposition of the Great Vessels PA leaves left ventricle & aorta leaves right ventricle with no connection systemic defects must be present to allow systemic circulation or pulmonary for mixing of blood Symptoms – cyanotic, cardiomegaly Treatment – Prostoglandin E, arterial switch with re-implanting coronary arteries prostaglandin E keeps PDA open which because aorta is coming off the right ventricle = lower pressure TGV because you have a PDA = pressure is higher is pulmonary artery and allows for oxygenated blood to go through the PDA and into the aorta because blood flows through lower pressure in this case so if the aorta has a lower pressure the the PDA allows the blood to flow in and not back however, lets say in regular PDA defect the pressure in the aorta is higher than the pulmonic artery which means blood backflows. the other thing they'll do is create a ASD of a PFA to allow for oxygenated blood to come from left atrium to right atrium to the right ventricle to go into systemic circulation but it will be mixed blood (oxygenated blood from the left side coming to the right and mixing with the blood from the right going into systemic circulation) this defect is correct within the first few days of life. they'll do an arterial switch and close the PFA or the ASD hardest part is re-implanting the coronary arteries  high mortality; parents can be given the option of comfort care they usually need a heart transplant Hypoplastic Left Heart Underdevelopment of left side of heart ventricle and aorta. Aortic atresia Requires PFO or ASD Systemic circulation from PDA Symptoms – mild cyanosis with CHF, after PDA closes progressive deterioration small lv and small aorta you need a PFA or ASD and a PDA Treatment * Prostoglandin E g Surgery 1. Norwood – main pulmonary artery to aorta 2. Bidirectional Glenn 3. Modified Fontan no pressure at all  Norwood Procedure · right side of the heart becomes the left side of the heart LA to RA to RV via ASD or PFO and Systemic Circulation Fontan Procedure Fontan Procedure  Truncus Arteriosis main artery never biforcates  Total Anomalous Pulmonary Venous Connection pulmonary veins empty some where else other than the left atrium; they empty in the right atrium  Congestive Heart Failure Volume overload – left to right shunts Pressure overload – obstructive defects ↓ contractibility – cardiomyopathy affects the muscle to heart High cardiac output demands – sepsis, anemia  Types Right sided heart failure * edema * hepatomegaly Left sided heart failure * respiratory distress * congestion  Clinical Manifestations Due to ↓ myocardial contraction, ↑afterload & ↑preload Increased Preload: Signs & symptoms When the heart contracts weakly, less blood is ejected, causing blood to remain in the ventricles during diastole, which stretches the ventricular walls and increases the end-diastolic > tachycardia volume, thereby increasing preload. > diaphoresis > easily fatigued Increased Afterload: > tachypnea A weakened contraction results in a less forceful ejection of blood, leading to a higher pressure in the aorta and systemic > dyspnea circulation that the heart must overcome to pump blood out, effectively increasing the resistance against which the heart > mild cyanosis contracts (afterload). - this is your resting aortic pressure that must be exceeded to open the aortic valve to eject blood. > retractions, grunting remember in isovolumetric contraction (pressure in the ventricles must exceed aortic pressure to eject) > wheezing, cough > poor profusion > hepatomegaly > edema, weight gain > developmental delays  Management Improve cardiac function 1.Digoxin - ↑cardiac output by increasing contraction - ↓heart size by decreasing heart rate - ↓venous pressure enhacing diuresis by increasing renal profusion - relief of edema check pressures before giving this medication 2. Ace inhibitors – Captopril, Enalapril, before administration auscaltate heart for a full minute to monitor for dig toxicity (bradycardia) know normal heart rates for age ranges digoxin should be given in micrograms if giving liquid digoxin; ask someone to check your dose check potassium as well too before giving dig cause you can get dig toxicity with hypokalemia Remove accumulated fluid & Na+ 1. Diuretics – lasix, aldactone lasix gets rid of sodium and potassium aldactone = potassium sparing 2. Possible fluid restriction & Na+ restriction Decrease cardiac demands 1. Provide neutral thermal environment 2.Treat existing infections 3. Decrease effort to breath elevate hob 4. Provide rest periods cluster care Improve tissue oxygenation- cool humidified O2 vasodilator  Nutrition Positioning Maintain nutritional status * ↑BMR they need more calories they poop more * well rested before feeding * q 3 hour feeds, ½ to finish feeding you want a NG tube place in place before feeding * may need to gavage after nippling * soft preemie nipple * semi-upright position * ↑calories/oz. instead of volume formula more concentrated; but dont increase volume bacause its bad for HF  Hypoxemia tricuspid atresia Decreased arterial O2 saturation HHLS Aortic Stenosis Over time 2 physiologic changes occur in response to chronic hypoxemia to compensate for lack of oxygen  polycythemia – due to↑ RBC production causes blood to viscous; hematocrit can be high; increases risk for clots well hydration is important  clubbing – thickening & flattening of tips of finger & toes Children who are cyanotic since birth are ⑧ smaller, poor weight gain, dyspnea on exertion and fatigue easily Central Cyanosis Clubbing Hypercyanotic Spells -“tet” spells Defects with obstructive pulmonary blood flow & communication between ventricles when they cry = severly cyanotic G* knee-chest position G reduces venous return of the legs; we wanna reduce the venous return of * calm child desaturated blood to the heart; it also increases systemic vascular resistance; we divert deoxygenated blood from the aorta to the pulmonic artery to become oxygenated * 100% O2 ②* Morphine IV we give this at the same time as knee chest position; morphine reduces spasm opens up the pulmonary artery and allows more blood from to go out the pulmonary blood instead of diverting deoxygenated blood into the aorta * IV replacement fluid Knee-chest Position  Web sites www.rch.org.au/cardiology/defects.cfm www.cincinnatichildrens.org/health/heart www.chop.edu/Congenital-Heart-Defects www.nlm.nih.gov.../congenitalheartdefects  Online Resources for Pediatric Cardiac Auscultation The Auscultation Assistant Web site: http://www.wilkes.med.ucla.edu/inex.htm Blaufuss Medical Multimedia Laboratories Web site: http://www.blaufuss.org Heart Sounds and Murmurs Web site: http://www.dundee.ac.uk/medther/Cardiology/hsmur.html Johns Hopkins University Cardiac Auscultatory Recording Database Web site: http://www.murmurlab.com/card6/ (registration required) Texas Heart Institute Web site: http://www.texasheart.org/education/cme/explore/events/eventdetail_5469.cfm University of Michigan Heart Sound and Murmur Library Web site: http://www.med.umich.edu/lrc/psb/heartsounds/index.htm University of Washington Department of Medicine Demonstrations: Heart Sounds and Murmurs Web site: http://depts.washington.edu/physdx/heart/demo.html