Cardiovascular

Common Cardiovascular Disorders in Children Congenital Heart Defects Congestive Heart Failure Acquired Heart Disease

Review of Normal Circulation

How to Understand Congenital Defects Think of blood as: Red highly O2 saturated Blue unsaturated Purple medium O2 saturated (mixed) Lavender- reduced volume of medium O2 saturated (mixed) Pink reduced volume of O2 saturated Light Blue Reduced volume of unsaturated

Fetal Circulation

Fetal Circulation

Fetal Shunts foramen ovale shunts mixed blood from right atrium to left atrium (hole in the atrial septum) ductus arteriosus accessory (extra) artery, shunts mixed blood away from lungs to descending aorta ductus venosus accessory (extra) vein, carries oxygenated blood from umbilical vein into lower venous system

Fetal hemoglobin carries 20-30% more oxygen than maternal hemoglobin How does the fetus receive sufficient oxygen from the maternal blood supply? Fetal hemoglobin carries 20-30% more oxygen than maternal hemoglobin Fetal hemoglobin concentration is 50% greater than mother’s Fetal heart rate 120-160bpm (increases cardiac output)

Newborn

What happens to the shunts after birth?

Transition from intrauterine to extra- uterine life Cord is clamped Neonate initiates respirations O2 levels rise Greater pressure in the left atrium Decreased pressure in the right atrium Immediate closure of foramen ovale

Transition from intrauterine to extrauterine life After O2 circulates systemically, over 24 hours, the pressure in the left ventricle will become greater than the pulmonary artery and closes the ductus arterosis The absent flow of blood through the umbilicus gradually closes the ductus venosus over 12 hr to 2 weeks

Cardiac Defects Either Ductal closure failure (no structural abnormality) Structural abnormality

Cardiac Catheterization Primary method to measure extent of cardiac disease in children Shows type and severity of the CHD Insert tiny catheter through an artery in arm, leg or neck into the heart Take blood samples and measure pressure, measure o2 saturation, and as an intervention

Cardiac Catheterization-Post Op Monitor closely (cardiac monitor, continuous pulse ox) VS q 15 Assess dressing at insertion site for infection, hematoma Dressing must remain dry for 1st 48-72 hrs Palpate a pulse distal to the dressing to assure blood flow Keep extremity straight for 48 hrs after procedure

If Congenital Defect is suspected or confirmed, Intervention is Important to Prevent CHF

Congestive Heart Failure

Congestive Heart Failure Heart doesn’t pump blood well enough Can not provide adequate cardiac output due to impaired myocardial contractility Causes in children: Defects Acquired heart disease Infections

Congestive Heart Failure Most common cause in children is congenital heart defects Increased volume load or increased pressure in heart Excess volume and pressure builds up in lungs leading to labored breathing Builds up in rest of body leading to edema

Congestive Heart Failure Symptoms 1st sign is tachycardia tire easily rapid, labored breathing decreased urine output increased sweating, pallor peripheral edema

CHF Diagnosis and Treatment CXR- shows enlargement Echocardiogram- dilated heart vessels, hypertrophy, increase in heart size Treatment is aimed at reducing volume overload, improve contractility May require surgery

Congestive Heart Failure Medical Management Digoxin Lasix Potassium

Digoxin Strengthen the heart muscle, enables it to pump more efficiently Digoxin toxicity: vomiting, bradycardia Need HR, EKG, drug levels Check apical pulse first, don’t give if HR < 100 bmp in infants and < 70 bpm in children Parents need teaching to assess apical pulse

Lasix Helps the kidneys remove excess fluid from the body Potassium wasting Must administer potassium supplements

Congenital Heart Defects

Congenital Heart Disease 35 different types Common to have multiple defects Range from mild to life threatening and fatal Genetic and environmental causes

Blood Flows From High to Low Pressure Higher pressure Lower Pressure

Types of Congenital Heart Defects Acyanotic Defects Cyanotic Defects Purple blood (mixed and too much blood sent to lungs but not enough to cause cyanosis) Septal defects Ventra Septal Defect (VSD) Atrial Septal Defect (ASD) Patent Ductus Arteriosis(PDA) Light blue blood (too little sent to lungs) Pulmonic Stenosis Pink blood (too little O2 sent to body) Coarctation of the aorta Light blue & purple blood (poor perfusion to lungs and body) Tetrology of Fallot

Acyanotic Defects

Septal Defects- increased pulmonary blood flow Left to right shunting (acyanotic defect) Sends already sat blood back to lungs Increased cardiac workload Excessive pulmonary blood flow Right ventricular strain, dilation, hypertrophy

Ventricular Septal Defect (VSD) Most common CHD Hole in ventral septum High Pressure in LV forces blood back to RV Results in increased pulmonary blood flow Higher than normal artery pressure

Symptoms Size of the defect varies Loud harsh systolic heart murmur Right ventricular hypertrophy O2 level of RV higher than normal on catheterization

Treatment Small defects Medical Management (Digoxin, Lasix, K+) Prophylactic antibiotics to prevent infective endocarditis Close spontaneously Large defect May develop CHF, poor feeding, failure to thrive Suture or patch hole closed (open heart surgery with cardiopulmonary bypass) Pulmonary artery banding to reduce blood flow to lungs if not stable for surgery

Atrial Septal Defect (ASD) Hole in atrial septum Pressure in LA is greater than RA (blood flows left to right) Oxygen rich blood leaks back to RA to RV and is then pumped back to lungs Results in right ventricular hypertrophy

Symptoms Harsh systolic murmur Second heart sound is split: “fixed splitting” ** diagnostic of ASD Pulmonary valve closes later than aortic valve- risk for pulmonary edema Fatigue and dyspnea on exertion Poor feeding, failure to thrive Large defect may cause CHF

Treatment Medical Management (Digoxin, Lasix, K+) Prophylactic antibiotics to prevent infective endocarditis Not expected to close on own Suture or patch hole closed (open heart surgery with cardiopulmonary bypass) Pulmonary artery banding to reduce blood flow to lungs if not stable for surgery

Patent Ductus Arteriosus (PDA) Failure of ductus arteriosus to close completely at Blood from the aorta flows into the pulmonary arteries to be reoxygenated in the lungs, returns to LA and LV More common in preemies H to L

Symptoms Preterm infants born with CHF and respiratory distress Fullterm infants may be asymptomatic with a continuous “machinery” type murmur Tire easily, growth retardation (shorter, weigh less, less muscle mass) Prone to frequent respiratory tract infections

Treatment Administration of Indomethacin (prostaglandin inhibitor) to stimulates ductus to constrict Surgical management ductus is divided and ligated Usually performed in first year of life to decrease risk of bacterial endocarditis

Summary of Acyanotic Defects VSD & ASD Rt hypertrophy Pulm edema Pulm htn PDA

Cyanotic Defects

Cynaotic Defects- decreased pulmonary blood flow Right to left shunting- sends unsaturated blood into O2 saturated blood and circulates to body Pulmonic Stenosis Coarctation of the Aorta Tetralogy of Fallot

Pulmonary Stenosis Valve Stenosis Obstruction of the right ventricular outflow tract Decreased pulmonary blood flow

Symptoms Systolic ejection murmur with a palpable thrill Right ventricular hypertrophy Mild to moderate cyanosis from reduced pulmonary blood flow High ventricular pressure may cause blood to back up into right atrium and force foramen ovale to open to allow blood to flow from right to left atrium Can lead to right ventricular failure, CHF

Treatment Surgical Management Medical Management (Digoxin, Lasix, K+) Oxygen Prophylactic antibiotics to prevent infective endocarditis Surgical Management Pulmonary balloon valvuloplasty via cardiac cath If unsuccessful valvotomy

Coarctation of Aorta Constriction of the aorta at or near the insertion site of the ductus arteriosus Reduces cardiac output (impedes blood flow from heart to body=pink blood) Aortic pressure is high proximal to the constriction and low distal to the constriction-Risk for CVA Higher pressure Pink Blood

Symptoms Systolic murmur BP is about 20 mm/Hg higher in arms than in lower extremities Upper extremity hypertension Diminished pulses in lower extremities Poor lower body perfusion Lower extremity cyanosis

Treatment Medical Management (Digoxin, Lasix, K+) Oxygen Administration of PGE1 (prostaglandin) infusions Maintain ductal patency and improves perfusion to lower extremities- although will cause increased pulmonary flow Surgical repair within first 2 years

Tetralogy of Fallot Consists of 4 Defects VSD RV hypertrophy Blood is light blue Consists of 4 Defects VSD RV hypertrophy Pulmonic Stenosis Overriding aorta Blood is purple

Symptoms cyanotic at birth when PDA closes increased respiratory rate, may lose consciousness “tet spells” or hypercyanotic episodes often preceded by crying, feeding or stooling tire easily especially with exertion, difficulty feeding and gaining weight become increasingly cyanotic over the first few months symptoms of chronic hypoxemia

Treatment Knee-chest position then apply O2 Treatment of tet spells Knee-chest position then apply O2 Do not leave alone- cyanosis can cause LOC, death

Symptoms Medical management Symptomatic newborn: PGE1 infusion to maintain ductal patency Digoxin, Lasix, K+ Older infants: close monitoring for worsening of hypoxia Surgical management: done at 3-12 months of age, in stages primary open-heart repair: close VSD, open pulmonary valve, remove obstructing muscle

Caring for the Child with a Congenital Heart Defect Taking infant home before corrective surgery Provide parents with information about care Review steps for follow-up care, emergency management (s/s respiratory distress, CPR) Key: promote normalcy within the limits of the child’s condition

Caring for the Child with a Congenital Heart Defect Preoperative:undergoing corrective surgery Explain procedures to parents and child, assure understanding Encourage child and parents to express fears Prepare child for surgery and post-op, show models of equipment (chest tube)

Caring for the Child with a Congenital Heart Defect Postoperative: Monitor cardiac output Support respiratory function Maintain fluid and electrolyte balance Promote comfort (IV morphine, sedatives) Promote healing and recovery

HTN Endocarditis Rheumatic Fever Kawasaki Disease Acquired Heart Diseae HTN Endocarditis Rheumatic Fever Kawasaki Disease

Hypertension Primary HTN Secondary HTN Caused by increased body mass Genetics Secondary HTN Cause is from an underlying condition such as kidney disease or heart defects

Hypertension No set systolic and diastolic number for diagnosis Need to compare to child’s age, gender and height If 3 different readings are above the 95th percentile for that child then diagnosis is confirmed

Hypertension Managed by eliminating the primary cause if possible Exercise, life style modification ACE inhibitors ARBs Beta-Blockers Ca Channel Blockers

Infective Endocarditis Inflammation of the lining of the valves and arteries Caused by bacterial and fungal infections in the blood stream that infects an already existing injured endocardium Children at risk: cardiac defects, severe valve disorders

Infective Endocarditis Symptoms: Fever, fatigue, headache, N/V, new or changed murmur, CHF, dyspnea Treatment: Antibiotics IV for 2-8 weeks, surgery to replace valves, treatment of CHF

Rheumatic Fever Acute RF is leading cause of acquired heart disease (but has decreased in US b/c abx) Inflammatory autoimmune condition Seen in children age 5-15 Usually follows untreated strep A infection (pharyngitis) Causes scarring of the mitral valves

Symptoms Tachycardia Polyarthritis Chorea Erythema marginatum (nonpuritic) Subcutaneous nodules Carditis

Treatment Treat current strep infection Treat other symptoms Streptococcal prophylaxis for 5 years Penicillin IM every month or Penicillin by mouth twice daily

Kawasaki Disease Acquired heart disease in children under age 5 Occurs due to antibody vascular injury post infection Boys>girls Asian decent Multisystem vasculitis (inflammation of blood vessels) 3 stages of illness Affects the coronary arteries

Kawasaki Disease first stage day 1-14 Prolonged fever Bilateral, nonpurulent conjunctivitis Changes in mouth (erythema, fissures, crusting of lips, strawberry tongue) Induration of hands and feet Erythema of palms and soles Erythemous rash Enlarged cervical lymph nodes

Kawasaki Disease second stage day 15-25 Fever and most of the previous symptoms resolve Extreme irritability develops Anorexia Lip cracking and fissuring Desquamation of fingers and toes Arthritis Vascular changes in myocardium and coronary arteries if untreated

Kawasaki Disease Third phase- day 26-40 Lasts until all symptoms disappear

Management Prevent or reduce coronary artery damage Gamma- globulin IV followed by High dose aspirin therapy at same time (80- 100mg/kg/ day once daily), continued through weeks 6-8 of disease Management Prevent or reduce coronary artery damage Gamma-globulin IV started in phase 1 High dose aspirin therapy at same time (80- 100mg/kg/day once daily) started in phase 2 Continued through weeks 6-8 of disease

Practice Questions!

The indicated area on the diagram showed higher than anticipated oxygen level on cardiac catheterization. The nurse concludes that is diagnostic for which CHD? (Select All that Apply) 1. PDA 2. VSA 3. Coartation of Aorta 4 ASD 5. Tetrology of Fallot

Don’t worry. This type of behavior is typical for a toddler A parent of a toddler with Kawaski’s disease tells the nurse “I just don’t know what to do with my child. He’s never acted like this before.” The nurses best reply is: Don’t worry. This type of behavior is typical for a toddler Irritability is part of Kawasaki’s disease. Please don’t be embarrassed Perhaps your child would benefit from stricter limits You seem to be in need of a referral to our Child Guidance Center

When assessing a child for signs and symptoms of rheumatic fever, which symptoms should the nurse anticipate? Tachycardia and joint pain Bradycardia and swollen joints Loss of coordination and pruritic rash Poor weigh gain and fever

The nurse assessing a newborn and auscultates a split S2 The nurse assessing a newborn and auscultates a split S2. The nurse should further assess for: Cyanosis Crackles Hypoxemia Blood pressure differences in extremities

Which nursing intervention is most effective in preventing rheumatic fever in children? Refer children with sore throats for a throat culture Include an ECG in the child’s yearly physical examination Assess the child for a change in the quality of the pulse Assess the child’s blood pressure

A newborn with patent ductus arteriousus is scheduled to receive indomethacin. The nurse administers this medication to: Open the ductus arteriosus Close the ductus arteriosus Enlarge the ductus arteriosus Maintain the size of the ductus arteriosus

Which congenital heart defect necessitates that the nurse take upper and lower extremity blood pressure readings? Coarctation of the aorta Tetralogy of Fallot Ventricular septal defect Patent ductus arteriosus

Notify the pediatrician as soon as possible An infant with ventricular septal defect develops congestive heart failure and is placed on digoxin therapy twice a day. The infant vomits the morning dose of digoxin. The most appropriate nursing intervention is to: Notify the pediatrician as soon as possible Take the infant’s pulse for 1 minute and repeat the dose of digoxin Skip the dose and give twice the amount at the next dose Repeat the dose and chart that the infant vomited the first dose

The parents of a newborn with small ventricular septal defect ask why their baby is being sent home instead of undergoing immediate open heart surgery. The nurse’s best response is: Your baby’s condition is too serious for immediate open heart surgery Ventricular septal defects are not repaired until the infant is older Your baby has a small defect, and it is likely to close spontaneously Your baby must be fully immunized before surgery

An infant with tetralogy of Fallot becomes hypoxic following a prolonged bout of crying. The nurse’s first action should be to: Administer oxygen Administer morphine Place the infant in the knee-chest position Comfort the infant