Cardiac Alterations Flashcards
In a fetus, what does the foramen ovale do?
Allows blood to pass from the right to left atrium
What does the ductus venosus do?
Channel blood from the umbilical vein to the inferior vena cava and into the right atrium
When does the foramen ovale close?
When pressure in the left atrium exceeds that of the right atrium
Ductus arteriosus constricts in response to what?
Higher oxygen saturation
What is the leading cause of death excluding prematurity during the first year of life
Congenital defects
Which ventricle is larger?
Right ventricle is initially larger than left
Immature heart is more sensitive to _________ and __________ __________.
Volume or pressure overload
Newborns cardiac output primarily depends on what?
Heart rate
At what age is the heart muscle fully developed?
Five years of age
What is congestive heart failure?
A congenital disorder, cardiac output is inadequate to support bodies circulatory and metabolic needs. There is increased pulmonary bloodflow and obstructed outflow and problems with hard contractility
What are some pathological conditions that lead to congestive heart failure?
Severe anemia, acidosis, respiratory disease
Left-sided heart failure results in what?
Pulmonary edema
What is left-sided heart failure?
The left ventricle is unable to pump blood into systemic circulation. Increased pressure in the left atrium and pulmonary veins
Describe right-sided heart failure.
The inability to pump blood into the pulmonary artery, increased pressure in the right atrium and systemic venous circulation.
What does right-sided heart failure cause?
Causes hepatosplenomegaly and occasional edema
Eventually, heart failure is ___________
Bilateral
Heart failure results in __________ ________ _______
Inadequate cardiac output
Inadequate cardiac output results in what problem with the organs and tissues?
poorly oxygenated organs and tissues
What happens to the kidneys and heart muscle in congestive heart failure?
The kidney stimulate sodium and water reabsorption causing fluid overload. The heart muscle becomes hypertrophied
What are signs and symptoms of congestive heart failure?
Tachycardia, decreased cardiac output: poor perfusion, cold extremities, weak pulses, slow capillary refill, low blood pressure, mottled skin. Pulmonary congestion: tachypnea , dyspnea , retraction, nasal flaring. Diaphoresis: during feeding and at rest. Pulmonary edema, orthopnea, wheezing, cough, gasping and grunting respirations
What is management of CHF?
Improve cardiac function: digitalis glycosides (digoxin), angiotensin converting enzyme inhibitors (captopril). Remove accumulate fluid and sodium: Lasix for Rappa diuresis, diurnal for maintenance diuresis. Decreased cardiac commands. Improve tissue oxygenation
What should be done prior to the administration of digoxin?
Apical pulse should be counted for one minute prior to administration
What are signs of digitalis toxicity?
Bradycardia, vomiting , neurological or visual disturbances
What needs to be monitored carefully when administering digoxin?
Serum k levels
How does CHF need to be managed differently in infants?
Infants with CHF have an increased metabolic rate and need additional calories above the normal baseline requirements to promote growth. As a result of poor weight gain and activity intolerance infants may demonstrate developmental delays
Fetal heart development occurs during what weeks of pregnancy? When do defect usually occur?
Fourth and seventh weeks of gestation, defects occur during the first eight weeks
Congenital heart defect’s are combined result of genetic and environmental factors. What are some genetic and environmental factors that may cause defects?
Fetal exposure to drugs and alcohol. Maternal viral infections, age, metabolic disorders, complications of pregnancy. Genetic factors: chromosome, family pattern
What are the two classifications of congenital heart defect’s?
Acyanotic, cyanotic
What is an acyanotic heart defect?
A defect with increased pulmonary bloodflow
What are three acyanotic heart defects?
Atrial septal defect’s, ventricular septal defect’s, patent ductus arteriosus
What are acyanotic obstruction to bloodflow from ventricles?
Coarctation of aorta, aortic stenosis, pulmonary stenosis
What is a cyanotic heart defect?
A defect the decreases pulmonary bloodflow or mixed blood flow
What is a heart defect that decreases pulmonary bloodflow?
Tetralogy of fallot
What is a heart defect with mixed blood flow?
Transposition of the great vessels
What are consequences of congenital heart defect?
Congestive heart failure, and hypoxemia
What is the most common type of defect?
Acyanotic defects
What is a connection between the left and right side of the heart?
Septal defect
What is the connection between the great arteries?
Patent ductus arteriosus
And acyanotic heart defect does what?
Permits blood to flow from higher to lower pressure from left to right. It increases vascular resistance, pulmonary hypertension. Right ventricular hypertrophy
What is an atrial septal defect
An opening in the arterial wall, it may vary in size
What are symptoms of an atrial septal defect?
Children are frequently asymptomatic. They may develop CHF, tire easily, and have poor growth. May have soft systolic ejection murmur
Patients with an atrial septal defect’s are at risk for what?
Atrial arrhythmias
What are treatments for an atrial septal defect?
Sometimes there a spontaneous closure with in four years. A Dacron patch to close moderate to large defects, ASD may require repair or replacement of the mitral valve
What is the prognosis and mortality rate for ASD?
The prognosis is excellent and mortality is less than 1%