PATHOPHYSIOLOGY
Congenital heart disease (CHD) occurs in approximately 8 out of 1,000 live births. In most cases, the specific cause is unknown. Inheritance,
genetic predisposition, and environmental influences (such as viruses, alcohol, and drugs) have been associated with CHD. Certain chromosomal aberrations, such as trisomies 13, 18, and 21, also increase the risk of CHD.
Congenital heart defects can be categorized as either acyanotic or cyanotic lesions.
Acyanotic cardiac defects can be further divided into lesions with
increased pulmonary blood flow (such as ventricular septal defect) and lesions with obstruction to blood flow from the ventricles (such as coarctation of the aorta).
Cyanotic defects can be further divided into lesions with decreased pulmonary blood flow (such as tetrology of Fallot) and lesions with mixed defects (such as transposition of the great arteries). Cardiovascular surgery can be performed for palliation and/or correction of many cardiac defects.
The postoperative nursing care plan that follows applies to children who have been moved out of the intensive care unit setting. For immediate postoperative care, consult a pediatric critical care nursing care plan book.
The basic pathophysiologies of 12 congenital heart
defects are presented here.
Acyanotic Heart Defects/Lesions with Increased Pulmonary Flow
Atrial Septal Defect (ASD) An atrial septal defect is an opening between the right and left atrium. It can vary in size and location in the septum and can be associated with other cardiac defects. Some of the oxygenated
blood going to the higher-pressure left atrium is shunted through the ASD to the lower-pressure right atrium; thus, an ASD is a left-to-right shunt. From the right atrium, the blood passes through the tricuspid valve to
the right ventricle; it then recirculates through the lungs, increasing the blood flow to the lungs.
Pulmonary vascular changes occur very slowly, and increased pulmonary
vascular resistance usually does not occur until early adulthood. Small ASDs may close spontaneously. Surgical intervention to close the ASD is recommended by school age. Earlier closure is recommended if the
child is experiencing problems. Nonsurgical closure is also possible using transcatheter devices during cardiac catheterization. Most children with an ASD are asymptomatic. ASD occurs in approximately 6 to 10% of all
congenital cardiac defects.
Atrioventricular (AV) Canal Defect Atrioventricular canal defect, also called endocardial cushion defect, refers to a combination of defects in the atrial and ventricular septal and portions of the mitral and tricuspid
valves allowing free communication of blood flow between all four chambers of the heart. In the most complex of these malformations a large central atrioventricular valve is created by clefts of the mitral and tricuspid valves with the presence of a low atrial septal defect and a high ventricular septal defect.
Aleftto- right shunt (most common), right-to-left shunt, and/or bidirectional shunt may exist. Oxygenated blood is recirculated to the lungs. Increased blood flow going under increased pressure to the lungs can lead to increased pulmonary vascular resistance and pulmonary
hypertension, which can ultimately result in congestive heart failure. Surgical repair is usually performed in infancy. Prior to surgical repair, medical management of congestive heart failure is initiated and
weight gain is emphasized.
Clinical manifestations include symptoms of congestive heart failure, and the infant appears small and undernourished. Cyanosis, which worsens with crying, is also present. AV canal defect occurs in 3 to 4% of children with congenital cardiac defects, and it is the most common cardiac defect
in children with Down syndrome.
Patent Ductus Arteriosus (PDA) The ductus arteriosus, a connection between the pulmonary artery and the descending aorta, is a normal pathway in fetal circulation that usually closes permanently during the
first few weeks of life. Failure of the ductus arteriosus to close results in a left-to-right shunt.
Oxygenated blood flows from the higher-pressure aorta into the
lower-pressure pulmonary artery and is recirculated through the lungs. The lungs then receive increased blood flow under increased pressure. If the patent ductus arteriosus is not corrected, irreversible pulmonary vascular disease can result. Some PDAs may close spontaneously. Surgical treatment, either by ligation (tying off) or division (cutting) is recommended for closure.
The use of prostaglandin inhibitor (indomethacin) is often used for closure of PDAs in preterm infants who are symptomatic. Older infants and children who have not had spontaneous closure will also require closure
by surgical intervention or by transcatheter closure done during cardiac catheterization.
Clinical manifestations may include a machinery-like murmur associated
with a thrill, widened pulse pressure, frequent respiratory infections, failure to thrive, and signs/symptoms of congestive heart failure. This defect accounts for 9 to 12% of all congenital cardiac defects.
Ventricular Septal Defect (VSD) A ventricular septal defect is an abnormal opening between the left and right ventricles. It can vary in size, location in the septum, and number (there can be multiple VSDs). AVSD
is often associated with other, more complex defects. It causes a left-to-right shunt that results in increased blood flow going to the lungs under increased pressure.
This increased blood flow has already been oxygenated and is recirculating through the lungs. Irreversible pulmonary vascular changes can result (usually when the child is around 2 years of age) if the condition is not
corrected. Approximately 60% of all VSDs close spontaneously sometime during the first 2 years of life.
Surgical intervention for closure of the VSD is required when the child is symptomatic and the defect does not close spontaneously. Nonsurgical treatment using device closure may also be used.
Clinical manifestations may include a loud, harsh, pansystolic murmur, frequent respiratory infections, failure to thrive, and signs/symptoms of congestive heart failure. VSD is the most common heart lesion occurring in approximately 20% of all children with congenital cardiac defects.
Acyanotic Heart Defects/Lesions with Obstruction to Blood Flow
Aortic Stenosis (AS) Aortic stenosis is a narrowing of the aortic outflow tract obstructing blood flow to the systemic circulation. It can be supravalvular, valvular, or subvalvular, with valvular being the most common. Pressure builds on the left side of the heart, due to the
resistance to ejection of blood from the left ventricle, and causes left ventricular hypertrophy. Left atrial pressure then increases, causing increased pressure in the pulmonary veins.
The increased pulmonary vascular pressure causes fluid to leak into the interstitial spaces, which results in pulmonary edema. Newborns with severe AS need their ductus arteriosus to remain patent (with the use of Prostaglandin E1) until the aortic valve can be dilated. When necessary balloon dilatation of the aortic valve may be done during cardiac
catheterization or surgically. If the condition is severe, the aortic valve is surgically replaced. Often, the child will require more than one procedure during his/her lifetime. There is a lifelong risk of endocarditis. Infants
with AS can manifest symptoms of left ventricular failure and low cardiac output such as respiratory distress, faint peripheral pulses, decreased urine output, and poor feeding.
If AS is not severe, it may go undiagnosed until preadolescence, when the child may manifest symptoms such as fainting, dizziness, epigastric pain, or exercise intolerance. Acute dysrhythmias may develop and result in sudden death following exertion in some individuals. AS occurs in approximately 3 to 6% of all cases of congenital cardiac defects.
Coarctation of the Aorta (COA) Coarctation of the aorta is a narrowing of the aorta that can vary from mild constriction to total occlusion. The most common location is juxtaductal (at the junction of the ductus arteriosus on the aortic arch). The degree of narrowing determines the severity of the symptoms. In juxtaductal coarctation, blood flow to the lower part of the body is decreased, manifested by diminished pulses in the lower extremities.
Pressure builds proximal to the obstruction and results in upper extremity hypertension. Elective surgical correction is recommended within the
first 2 years of life to prevent hypertension. Nonsurgical treatment using balloon dilatation during cardiac catheterization may be used as a primary intervention or for recoarctation.
Clinical manifestations of congestive heart failure may be present in symptomatic infants with COA. Children with COA may be asymptomatic,
and the defect is first detected during a routine physical examination when upper extremity systemic hypertension, weak or absent femoral pulses, and a heart murmur are present. It occurs in about 5 to 8% of
all cases of congenital cardiac defects.
Pulmonary Stenosis (PS) Pulmonary stenosis is a narrowing at the area around the pulmonary valve, resulting in an obstruction that interferes with blood flow out of the right ventricle. The narrowing can vary
in degree from mild to severe and can be supravalvular, valvular, or subvalvular. Pressure builds in the right ventricle and can result in right ventricular hypertrophy. In young infants, this increase in pressure
may cause the foramen ovale to reopen, resulting in right-to-left shunting of unoxygenated blood.
If pulmonary stenosis is severe, systemic venous engorgement results and can lead to congestive heart failure. Balloon dilatation during cardiac catheterization or surgical intervention may be required to correct the
defect. Clinical manifestations may include a systolic ejection murmur, dyspnea, cyanosis, fatigue, and signs/symptoms of congestive heart failure. PS occurs in approximately 8 to 12% of all cases of congenital cardiac defects.
Cyanotic Heart Defects/Lesions with Decreased Pulmonary Blood Flow
Tetralogy of Fallot (TOF) Classic tetralogy of Fallot has four components: pulmonary stenosis, ventricular septal defect, an overriding aorta, and right ventricular hypertrophy (creating a boot-shaped heart as seen on X-ray). A fifth defect, either an open foramen ovale or an atrial septal defect may also be present in some children.
The pattern of blood flow in this defect is determined by the degree of pulmonary stenosis. If pulmonary stenosis is severe, pressure builds in the right ventricle and unoxygenated blood passes through the VSD into the overriding aorta (right-to-left shunt), producing cyanosis. If the pulmonary stenosis is mild and the pressure in the right ventricle is not increased, the
blood shunts left to right through the VSD and the child is acyanotic. In time, the pulmonary stenosis becomes more severe and the child becomes more cyanotic as less blood flows to the lungs.
Hypoxic, or “tet,” spells occur in some children with TOF. These spells are
thought to occur as a result of a transient increase in obstruction of the right ventricle outflow tract causing cyanosis and a decreased level of consciousness. Tet spells can be treated by placing the child in the kneechest position, which is thought to increase venous return to the heart and dilate the right ventricle and should decrease the pulmonary outflow obstruction effect.
Surgical correction involves closing the VSD and resectioning the infundibular stenosis and enlarging the right ventricular outflow tract. Elective surgery is usually performed prior to 1 year of age. If surgical correction needs to be delayed, a palliative procedure may be done prior to total correction in order to increase pulmonary blood flow.
Clinical manifestations may include cyanosis, hypoxemia, increased hemoglobin and hematocrit, and a pansystolic murmur. Since surgical
repair is usually done early (before the child is 1 year of age), squatting, once common, is rarely seen now.
There is a lifelong risk for endocarditis. Tetralogy of Fallot accounts for anywhere between 4 to 10% of all cases of congenital cardiac defects. It is the most common cyanotic congenital heart defect.
Tricuspid Atresia Tricuspid atresia is total occlusion of the tricuspid valve. There is no communication between the right atrium and the right ventricle. Other anomalies, such as atrial septal defect (ASD), ventricular
septal defect (VSD), or patent ductus arteriosus (PDA) are commonly present, and a mandatory rightto- left atrial shunt exists. The right ventricle is usually small, and the pulmonary arteries may also be small.
Blood returning from the body empties into the right atrium and cannot pass into the right ventricle; therefore, the blood goes through the ASD to the left atrium. From the left atrium, blood flows to the left ventricle,
and a portion of this blood goes to the lungs via a VSD. If a VSD is not present, the blood can flow to the lungs via a PDA. In infants with a PDA, prostaglandin E1 can be given to maintain the patency of the ductus arteriosus.
Palliative surgery designed to increase blood flow to the lungs may also be done prior to total correction. Total repair involves creating communication between the right atrium (or right ventricle) and the pulmonary artery. There is a lifelong risk for endocarditis.
The most consistent clinical manifestation is cyanosis in conjunction with tachypnea and dyspnea. Tricuspid atresia is an uncommon defect, occurring in 2.7% of all cases of congenital cardiac defects.
Cyanotic Heart Defects/Lesions with Mixed Blood Flow
Total Anomalous Pulmonary Venous Connection (TAPVC) Total anomalous pulmonary venous connection, also called total anomalous pulmonary venous return (TAPVR), occurs when the pulmonary
veins do not connect to the left atrium; instead, they connect to the right atrium or to one of the systemic veins draining toward the right atrium (such as the superior vena cava or the inferior vena cava).
The blood flow pattern in the heart depends on where the pulmonary veins connect (above or below the diaphragm) and on the presence or absence of pulmonary venous obstruction. In all types of TAPVC,
the right atrium ultimately receives systemic blood as well as the blood returning from the lungs. This increased blood flow to the right atrium results in hypertrophy of the right side of the heart.
The only way for blood flow to reach the left atrium is through an
associated atrial septal defect or a patent foramen ovale. When there is no pulmonary venous obstruction, excessive blood flow to the lungs occurs, which can result in congestive heart failure. If pulmonary venous congestion is present, blood flow to the lungs is decreased and cyanosis can be marked. Pulmonary venous pressure rises proximal to the obstruction, resulting in pulmonary edema. Surgical correction is required to repair TAPVC.
Clinical manifestations include cyanosis, a blowing systolic murmur, a venous hum, tachypnea, feeding difficulties, repeated upper respiratory infections, and signs/symptoms of congestive heart failure. TAPVC
occurs in approximately 1% of all cases of congenital heart defects.
Transposition of the Great Arteries (TGA) In transposition of the great arteries, the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle. This results in two separate circulatory
systems and can be life threatening at birth without the presence of a patent foramen ovale and ductus arteriosus. Blood from the systemic circulation enters the right atrium and passes to the right ventricle and
out the aorta back to the rest of the body without going to the lungs for oxygenation.
The pulmonary veins empty into the left atrium. The oxygenated blood goes to the left ventricle, out the pulmonary artery, and back to the lungs. Associated lesions (atrial septal defect, ventricular septal defect, and patent ductus arteriosus) are usually present and account for any mixing of oxygenated and unoxygenated blood.
Corrective surgery is usually performed before one week of life. Surgeries
for total correction involve an arterial switch procedure (preferred) or intraatrial redirection of blood flow. Balloon septostomy can be performed as a palliative procedure during cardiac catheterization in order to enlarge the interatrial communication and mixing of blood, resulting in a dramatic increase in arterial oxygenation. There is a lifelong risk for endocarditis.
Clinical manifestations may include cyanosis and signs/symptoms of congestive heart failure. The defect occurs in about 5% of all cases of congenital cardiac defects.
Truncus Arteriosus Truncus arteriosus is characterized by a single vessel that arises from the left and right ventricles and overrides a ventricular septal defect (VSD). This single vessel gives rise to pulmonary, systemic,
and coronary circulations. Blood from both ventricles enters the single vessel and flows to the lung and to the rest of the body. Blood flow to the lungs is usually under systemic pressure, depending on the type of
truncus present.
The type of truncus is determined by the existence and location of the main pulmonary artery and the pulmonary artery branches. Infants with
truncus arteriosus are usually at high risk for early pulmonary vascular disease because the blood flows under increased pressure to the lungs. Corrective surgery is usually performed in the first few months of
life. Palliative surgery may be done prior to corrective surgery and is aimed at decreasing pulmonary blood flow. There is a lifelong risk for endocarditis.
Clinical manifestations include cyanosis and signs/symptoms of congestive heart failure. Truncus arteriosus accounts for 1% of all cases of congenital cardiac defects.
Postoperative, Postpediatric ICU Nursing Care Plan
Primary Nursing Diagnosis : Decreased Cardiac Output
Definition: Decrease in the amount of blood that leaves the left ventricle
Possibly Related to:
• Surgical complications:
• thrombus
• ineffective circulation
• interference with electrical conduction of the heart
• dysrhythmias
• tachycardia or bradycardia
Assessment/Defining Characteristics of Child and/or Family:
Objective Data
• Tachycardia/bradycardia
• Dysrhythmias
• Hypotension/hypertension
• Unequal, decreased, or absent peripheral pulses
• Cyanosis
• Prolonged capillary refill, longer than 2 to 3 seconds
• Murmur, gallop, rub, click
Subjective Data
• Cool, pale skin
• Fever
• Activity intolerance
• Fatigue
• Decreased urine output
Expected Outcomes
Child will have adequate cardiac output as evidenced by
- heart rate, respiratory rate, and blood pressure within acceptable range (state specific range for each)
- strong and equal peripheral pulses
- brisk capillary refill within 2 to 3 seconds
- skin warm to touch
- strong and equal peripheral pulses
- adequate urine output (state specific range; 1 to 2 ml/kg/hr)
- lack of murmur, gallop, rub, click,cyanosis,fatigue
| Nursing Interventions | Rationale | Evaluation |
|---|---|---|
| Assess and record the following every 4 hours and PRN • HR, RR, and BP • peripheral pulses • capillary refill • any signs/symptoms of decreased cardiac output (such as those listed under Assessment) | If child experiences decreased cardiac output (CO) the HR, RR will increase and BP will decrease. Peripheral pulses will be weak and unequal. Capillary refill will be longer than 2 to 3 seconds. | Document range of HR, RR, and BP. Describe quality of peripheral pulses and capillary refill. Describe any signs/symptoms of decreased cardiac output noted. |
| Assess and record condition of dressing and/or incision site every shift and PRN. Notify physician of excessive drainage. | Excessive drainage or bleeding could result in decreased cardiac output. | Describe condition of dressing and/or incision site. |
| Administer cardiac drugs (such as digoxin) on schedule. Assess and record any side effects or any signs/symptoms of toxicity (such as vomiting with digoxin). Follow hospital protocol for administration, such as 2 RNs checking the dosage prior to administration and documenting the HR or BP at the time of medication administration. | Cardiac drugs are given to increase the strength of cardiac contractions and/or increase return of blood flow to the heart, thereby increasing CO. | Document whether cardiac medications were administered on schedule. Describe effectiveness and any side effects noted. |
| If indicated, monitor and record digoxin levels. Notify physician if levels are out of the acceptable range. (A decreased potassium level increases the risk for digoxin toxicity.) | Digoxin is a potent medication that needs careful monitoring. If digoxin levels are high, the child will experience signs/ symptoms of toxicity (such as vomiting). | Document digoxin levels. If levels are out of the acceptable range, describe any corrective measures implemented. |
| Ensure that chest physiotherapy is done on schedule. Record effectiveness and child’s response to treatment. | Chest percussion loosens secretions and positioning can help to assist the flow of secretions out of the lungs by gravity. | Document whether chest physiotherapy was done on schedule. Describe effectiveness and child’s response to treatment. |
| Elevate head of bed at a 30° angle. | Elevating the head of the bed to a 30° angle causes a shift of the abdominal contents downward and this will allow for increased lung expansion. | This will aid in reducing workload on the heart. Document whether head of bed was elevated. |
| Keep accurate record of intake and output. | Decreased output may indicate decreased CO possibly due to a shift of the intravascular fluid into the interstitial space. | Document intake and output. |
| Teach child/family about characteristics of decreased cardiac output. Assess and record results. | Increased knowledge will assist the child/ family in recognizing and reporting changes in the child’s condition. | Document whether teaching was done and describe results. |
Nursing Diagnosis : Acute Pain
Definition: Condition in which an individual experiences acute mild to severe pain
Possibly Related to :
• Incision site
• Treatments and procedures
Assessment/Defining Characteristics of Child and/or Family
Subjective
• Verbal communication of pain or tenderness
• Crying unrelieved by usual comfort measures
• Facial grimacing
• Restlessness
Objective Data
• Rating of pain on pain-assessment tool
• Physical signs/symptoms (tachycardia, tachypnea/bradypnea, increased blood pressure, diaphoresis)
Expected Outcomes
Child will be free of severe and/or constant pain as evidenced by
• verbal communication of comfort
• lack of constant crying, lack of extreme restlessness
• heart rate within acceptable range (state specific range)
• respiratory rate within acceptable range (state specific range)
• rating of decreased pain or no pain on pain-assessment tool
• lack of signs/symptoms of acute pain (such as those listed under Assessment)
• lack of diaphoresis
• lack of signs/symptoms of acute pain (such as those listed under Assessment)
| Nursing Interventions | Rationale | Evaluation |
|---|---|---|
| Assess and record HR, RR, BP, and any signs/ symptoms of pain (such as those listed under Assessment) every 2 to 4 hours and PRN. Use an appropriate pain assessment tool. | Provides data regarding the level of pain child is experiencing. | Document range of HR, RR, BP, and degree of pain child was experiencing. Describe any successful measures used to decrease pain. |
| When indicated, administer analgesics on schedule. Assess and record effectiveness. | Analgesics are administered to decrease pain. | Document whether analgesics were administered on schedule. Describe effectiveness and any side effects noted. |
| Encourage family members to stay and comfort child when possible. | Helps to comfort and support the child. | Document whether family was able to remain with child and describe effectiveness of their presence. |
| Use diversional activities (e.g., music, television, playing games, relaxation) when appropriate. | Diversional activities can distract child and may help to decrease pain. | Document whether diversional activities were successful in helping to manage pain. |
| Teach child/family about characteristics of pain. Assess and record results. | Increased knowledge will assist the child/ family in recognizing and reporting changes in the child’s condition. | Document whether teaching was done and describe results. |
| Teach child/family about care. Assess and record child’s/family’s knowledge of and participation in care regarding medication administration, etc. | Education of child/ family will allow for accurate care. | Document whether teaching was done and describe results. |
Nursing Diagnosis: Fear: Child/Family
Definition: Feeling of apprehension resulting from a known cause
Possibly Related to:
• Outcome of surgical procedure
• Pain and discomfort following surgery
• Unfamiliar surroundings
• Forced contact with strangers
• Treatments and procedures
Assessment/Defining Characteristics of Child and/or Family
Subjective Data:
• Uncooperativeness
• Regressed behavior
• Hostile behavior
• Restlessness
Objective Data:
• Inability to recall previously taught information
• Decreased communication
• Decreased attention span
Expected Outcomes
Child/family will exhibit only a minimal amount of fear as evidenced by
• ability to relate appropriately to family members and members
of the health care team
• lack of regressed or hostile behavior
• ability to rest and sleep when indicated
• ability to restate information previously taught
• ability to participate in care
| Nursing Interventions | Rationale | Evaluation |
|---|---|---|
| Assess and record level of child’s/family’s fear and the source of the fear. | Provides information about the level of fear and possibly the source of the fear. | Document level of fear and any identified sources of the fear. |
| Decrease child’s/family’s fears when possible by • encouraging family members to stay with child • encouraging child/family members to participate in care • assigning same staff members to provide care for child • spending extra time with child when family members are unable to be present • encouraging family members to bring in familiar articles and toys from home • explain to child/family what to expect during this recovery phase | These measures will help make the child and family members more comfortable and can help to decrease fear. | Document any measures used to help alleviate fear. State effectiveness of measures. |
| Initiate age-appropriate therapeutic play when indicated. Document effectiveness. | Play can be a useful distraction or outlet to help decrease fears. | Document whether therapeutic play was used and describe its effectiveness. |
| Encourage child/family to express fears to members of the health care team. | Expression and identification of fears can help the child/family to find ways to manage these fears. | Document any identified fears. |
| Encourage child/family to meet basic needs, such as eating and resting appropriately. Assist them as needed. | Assist child/family in decreasing stress, which can help to identify and alleviate fears. | Document whether child/family were able to separate for short periods so that family members could meet their own basic needs. |
| Teach child/family about characteristics of fear. Assess and record results. | Increased knowledge will assist the child/ family in recognizing and reporting changes in the child’s condition. | Document whether teaching was done and describe results. |
| Teach child/family about care. Assess and record child’s/family’s knowledge of and participation in care regarding appropriate diversional activities, etc. | Education of child/ family will allow for accurate care. | Document whether teaching was done and describe results. |
Atrendynurse 