Copyright © 2012 by Saunders, an imprint of Elsevier, Inc. Chapter 12 Cardiac Disorders.

Copyright © 2012 by Saunders, an imprint of Elsevier, Inc.

Chapter 12

Cardiac Disorders


Cardiovascular System

• Heart fully functioning by 8th week of gestation

• Fetal circulation: placenta is the organ of oxygenation– Ductus venosus

– Ductus arteriosus

– Foramen ovale

• The birthing process begins closure of fetal shunts

• Heart defects are the most common birth defect– Leading cause of birth defect-related deaths

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Congenital Heart Disease

• Description– A defect in the structure of the heart or in one or more of

the large blood vessels that lead to and from the heart– Multifactorial

• Result of genetic-environmental interactions

• Four classifications– Based on defect’s effect on blood flow

• Hemodynamics: study of blood circulation• Shunting: flow of blood through abnormal openings

– Defects with increased pulmonary blood flow– Obstructive defects– Defects with decreased pulmonary blood flow– Mixed defects

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Copyright © 2012 by Saunders, an imprint of Elsevier, Inc. 12-4


Congenital Heart Disease (CHD)

• Diagnostic tools– Not all testing is necessary for each child

– Lab tests, electrocardiogram, halter monitor, event recorder, chest radiography, echocardiogram, MRI, cardiac catherization

• Cardiac catherization is an invasive procedure• Provides information about anatomy, cardiac

pressure, oxygen saturation, cardiac function

• Sedation is necessary

• Entry site kept straight 4-6 hours after procedure

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Congenital Heart Disease (CHD)

• Signs and symptoms– Depend on location and type of heart defect– Child may be small for age, condition may be

classified as a physiologic failure to thrive– Exercise intolerance noticed anywhere from infancy

to toddler age– Clubbing of the fingers– Frequent respiratory infections because of

pulmonary vascular congestion– Squatting position (TET spell)– Polycythemia: Body compensates for hypoxemia by

increasing number of RBCs

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Clubbed fingers


Congestive Heart Failure (CHF)

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Defects with Increased Pulmonary Blood Flow

• Patent ductus arteriosus (PDA)– Passageway connecting pulmonary artery to aorta, avoiding

fetal lungs– Failure to close causes oxygenated blood to recycle through the

lungs• Overburdens pulmonary circulation• Makes heart work harder• One of the most common cardiac anomalies

– Symptoms• Machine-like murmur, dyspnea, bounding pulses on exertion, failure to

thrive, frequent respiratory infections– Treatment

• Indomethacin/ibuprofen in premature infants to close ductus• Amplatzer PDA device• Surgical repair

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• Atrial septal defect (ASD)– Abnormal opening between right and left atria– Common congenital heart anomaly– Symptoms

• Generally asymptomatic• Cyanosis if blood flow is reversed by heart failure• Large openings may cause failure to thrive

– Treatment• Open heart surgery• Percutaneous occluding devices

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• Ventricular septal defect (VSD)– Opening between right and left ventricles– 75% of small VSDs close spontaneously by age

10– Symptoms

• Loud, harsh murmur• Systolic tremor• Moderate/large defects may present CHF symptoms

– Treatment• Percutaneous transcatheter closure• Occluder devices

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Obstructive Defect

• Coarctation (tightening) of the aorta– Symptoms

• Increased pressure proximal to the defect

• Decreased pressure distal to the defect

• High blood pressure

• CHF symptoms

– Treatment• Balloon angioplasty

• Surgical intervention; anastomosis

• Risk of developing subacute bacterial endocarditis

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Defect with Decreased Pulmonary Blood Flow

• Tetralogy of Fallot– The most common cyanotic heart defect– Four defects

• Stenosis (narrowing of pulmonary artery)• Hypertrophy of the right ventricle• Over-riding aorta• VSD

– Symptoms• Cyanosis/hypoxemia episodes with hyperpnea, irritability• Hypoxia

– Treatment• Open heart surgery to correct defects

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Mixed Defect

• Transposition of the great arteries (TGA)– Pulmonary artery leaves left ventricle– Aorta leaves the right ventricle– Other defects (septal defects, PDA) must be present to

exchange blood which sustains life– Survival impossible without surgery– Symptoms

• CHF symptoms• Any murmur present is caused by other defects, not TGA

– Treatment• Prostaglandin E1 (keeps PDA open)

• Balloon atrial septotomy (opens septal wall)• Corrective surgery

– Performed within the first 2 weeks of life

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Mixed Defect

• Hypoplastic left heart syndrome (HLHS)– Left side of the heart is underdeveloped– Hypoplasia of aorta, left ventricle, mitral valve– Systemic circulation provided by right side of the

heart (Rt ventricle is force of circulation)– Ductus arteriosus and foramen ovale must

remain patent to survive with HLHS– Treatment

• PGE1 is administered to maintain a PDA• Surgery in several stages

– Norwood, Glenn, Fontan

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• Treatment and nursing care– Nursing goals in the care of the newborn

infant can be adapted for all children with heart defects

• Reduce the work of the heart• Improve respiration• Maintain proper nutrition• Prevent infection• Reduce the anxiety of the patient• Support and instruct the parents

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• Treatment and nursing care (continued)– Change child’s position frequently to prevent respiratory complications– Threat of cerebral thrombosis– Chest tubes may be used after surgery

• System must be airtight• Drainage containers always kept below the level of the chest

– Avoid unnecessarily disturbing the child; they need to conserve energy• Common medications

– Digoxin (Lanoxin)– Dopamine, dobutamine, epinephrine– Amrinone, milrinone– ACE inhibitors– Angiotensin II receptor blockers– Diuretics

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• Treatment and nursing care (continued)– Infective endocarditis (IE)

• High risk for children with complex cyanotic heart diseases or children who have had heart surgery

• Organisms grow on the endocardium or areas of turbulent blood flow

– Symptoms• Fever, fatigue, headache, nausea, vomiting

– Diagnosis and treatment• Blood cultures determine causative organism• Antibiotics

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• Home care– Family must understand medication administration

– Family must identify symptoms requiring medical attention

– Provide a normal environment within child’s limits

– Avoid allowing the child to gain control of the home• Limit setting

– Integrate the child into family life

– Explain the possible need for frequent hospitalization to parents and child

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Question 12.2

Which of the following is NOT one of the four classifications of congenital heart disease?

A.Defects with increased pulmonary blood flow

B.Congestive heart failure

C.Defects with decreased pulmonary blood flow

D.Mixed defects

12-20


Acute Rheumatic Fever

• Description– Follows infection with certain strains of Group

A beta-hemolytic streptococci

• Signs and symptoms– Abdominal pain, fever, pallor, fatigue,

anorexia, unexplained nosebleeds– Jones criteria aid in diagnosis of rheumatic

fever– ECG is sometimes a useful diagnostic

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• Treatment and nursing care– Elimination of the initial infection is followed

by long-term chemo-prophylaxis (prevention of disease by drugs)

– Intramuscular penicillin G benzathine (Bicillin), given as an intramuscular injection every 28 days

– Anti-inflammatory drugs are used to decrease pain and inflammation

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• Home care– Bed rest during the initial attack is not

necessary but is recommended if carditis is present

– Nurse must verify that parent and child understand activity limitations

• Parents should provide interesting quiet activities

– Long-term chemo-prophylaxis

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• Prevention– The nurse is involved in prevention of rheumatic

fever in the community by recognizing signs and symptoms of streptococcal infections, doing screening, and referring for treatment

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Copyright © 2012 by Saunders, an imprint of Elsevier, Inc. Chapter 12 Cardiac Disorders.

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