Fetal to Neonatal Circulation and PPHN

Cardiovascular System Development

• Fetal heart rate is present around postconceptual day 17
• Heart chambers and arteries form during gestational weeks 2-8
• Oxygenation occurs via the placenta in the fetus
• The fetus's lungs are perfused but don't perform oxygenation/ventilation
• The foramen ovale is an opening between the atria that allows blood flow from right to left atrium
• The ductus arteriosus allows blood to flow between pulmonary artery and aorta, shunting blood away from pulmonary circulation

Change from Fetal to Neonatal Circulation

• The change from fetal to neonatal circulation is visually represented in a diagram

Persistent Pulmonary Hypertension of the Newborn (PPHN)

• Marked pulmonary hypertension causes right-to-left extrapulmonary shunting and hypoxemia
• Nursing assessment includes tachypnea within 12 hours after birth
• Other signs include marked cyanosis, grunting, retractions, and systolic ejection murmur

PPHN: Nursing Management

• Monitor oxygenation, perfusion, and blood pressure
• Immediate resuscitation and oxygen therapy are key
• Respiratory support is needed
• Medications are indicated
• Minimize stimulation by clustering care
• Provide parental support and education

Cardiovascular Changes in Childhood

• Heart rate is faster in infancy (90-160 bpm) and decreases with age
• Blood pressure is lower in infancy (~80-55 mm Hg) and increases with age
• Heart rate and blood pressure reach adult levels by adolescence

Congenital Heart Disease vs Acquired Heart Disease

• Congenital heart disease involves structural anomalies present at birth
• Congenital heart disease accounts for the largest percentage of all birth defects
• Acquired heart disease involves disorders that occur after birth, like heart failure
• Acquired heart disease is a common reason for admission
• Acquired heart disease develops from a wide range of causes
• Acquired heart disease may be a complication or long-term effect of congenital heart disease

Hemodynamic Characteristics of Congenital Heart Defects

• Congenital Heart Disease is classified based on hemodynamic characteristics
• Disorders with decreased pulmonary blood flow include Tetralogy of Fallot and Tricuspid atresia
• Disorders with increased pulmonary blood flow include Patent Ductus Arteriosus (PDA), Atrial Septal Defect (ASD), and Ventricular Septal Defect (VSD)
• Obstructive disorders include Coarctation of the Aorta, Aortic Stenosis, and Pulmonary Stenosis
• Mixed disorders include Transposition of the Great Vessels (TGV), Total Anomalous Pulmonary Venous Return (TAPVR), Truncus Arteriosus, and Hypoplastic Left Heart Syndrome

Risk Factors for Cardiovascular Disorders in Childhood

• Congenital risk factors include congenital malformations, genetic syndromes, family history, maternal drug or alcohol exposure, and prematurity
• Acquired risk factors include infections, obesity, diabetes, drug or alcohol exposure, hypertension and chemotherapy
• Additional acquired risk factors include connective tissue/autoimmune/endocrine disorders, organ transplant and hyperlipidemia

Diagnostic Tests for Cardiovascular Disorders

• Pulse oximetry assesses oxygen saturation
• Electrocardiogram (ECG) and Holter monitoring evaluate heart's electrical activity
• Echocardiogram uses sound waves to create a moving picture of the heart
• Chest radiograph assesses the size and shape of the heart and lungs
• Exercise stress testing evaluates how the heart functions during physical activity
• Laboratory tests include CBC, BMP, C-reactive protein (CRP), and Erythrocyte sedimentation rate (ESR)
• Arteriogram and cardiac catheterization provide detailed images of blood vessels and heart chambers

Common Medical Treatments Table

• Oxygen: It's supplemented via mask, nasal cannula, hood, tent, or endotracheal/nasotracheal tube. It's indicated for hypoxemia, respiratory distress, or heart failure
• Chest physiotherapy (CPT) and postural drainage: It promotes clearance by mobilizing secretions with percussion or vibration accompanied by postural drainage. It's indicated for mobilization of secretions, particularly in the postoperative period or with heart failure
• Chest tube: A drainage tube that is inserted into the pleural cavity to facilitate removal of air or fluid to allow full lung expansion, indicated after open heart surgery/pneumothorax.
• Pacing: External wiring connected to a small generator used to electrophysiologically correct cardiac arrhythmias or heart block (temporary). Permanent pacing is achieved with an implantable internal pacemaker, indicated for Bradyarrhythmias, heart block, cardiomyopathy, sinoatrial, or atrioventricular node malfunction

Assessment of the Child Undergoing Cardiac Surgery

• Assess temperature and weight measurements
• Evaluate extremities for peripheral edema, clubbing, and peripheral pulses
• Auscultate heart, noting rate, rhythm, and heart sounds; listen for murmurs, clicks, and rubs
• Assess respiratory status, including respiratory rate, work of breathing, and breath sounds

Clinical Question and Answer

• Question: The nurse is assessing a child for cardiac disorders and documents the presence of clubbing of the fingers and toes. Which of the following conditions might this indicate?
• Answer: Hypoxia
• Rationale: Clubbing implies chronic hypoxia due to congenital heart disease, and usually won't appear until after 1 year of age. Fever is a sign of an infection. Cyanosis causes a bluish tint to the skin due to decreased oxygenation. Edema cause swelling or bloating due to fluid imbalance

Heart Failure

• Heart failure is a consequence of many congenital and acquired cardiovascular disorders
• Nursing management of heart failure includes promoting oxygenation
• Additional nursing interventions include supporting cardiac function, providing adequate nutrition, and promoting rest

Infective Endocarditis

• Infective Endocarditis: A bacterial infection of endothelial surfaces of the heart, commonly affecting the valves, chamber walls, or septum
• There is an increased risk with prosthetic valves
• Requires antibiotic treatment

Acute Rheumatic Fever

• The diagnosis of acute rheumatic fever requires the presence of either two major criteria or one major plus two minor criteria
• Major criteria include Carditis, Migratory polyarthritis, Subcutaneous nodules, Erythema marginatum and Sydenham chorea
• Minor criteria include Polyarthralgia, Elevated erythrocyte sedimentation rate or C-reactive protein, Prolonged PR interval (unless carditis is a major criterion)

Cardiomyopathy

• Risk factors: Congenital heart defect, genetic disorders, inflammatory or infectious processes
• Additional risk factors include post-transplant status (or postoperatively after cardiac surgery), hypertension, Duchenne and Becker muscular dystrophy
• Cardiomyopathy commonly has no known cause
• Cardiomyopathy may present as heart failure or cardiac arrest

Kawasaki Disease

• Signs and symptoms include high fever for 5 days that is unresponsive to antibiotics
• Additional signs and symptoms include chills, headache, malaise, extreme irritability, distinctive rashes (strawberry tongue, palmar erythema)
• Further Signs and symptoms include desquamation of perineum/fingers and toes, vomiting, diarrhea, abdominal and joint pain
• The treatment is IV immunoglobulin and aspirin
• Requires long-term monitoring of coronary arteries

History of the Present Illness

• Questions for History of Present Illness:
• Onset and progression of symptoms
• Treatments and medications used at home
• Activity level compared to peers
• History elements include Orthopnea, Dyspnea, Easy fatigability, Growth delays or failure to thrive, Squatting
• Additional elements include Edema, Dizziness, Frequent pneumonia, Poor feeding, Fatigue, Lethargy, Vomiting
• Final elements include Diaphoresis, Motor delays, Cyanosis and Tachypnea

Past Health History

• Consider problems occurring after birth
• Look for congenital malformation
• History of NICU stays?
• Frequent infections?
• Chromosomal abnormalities?
• Prematurity?
• Autoimmune disorders?
• Use of medications, such as corticosteroids?

Risk Factors for Cardiovascular Disorders

• Family history of heart disease or Congenital Heart Defects
• Investigate further if heart disease occurred in a first-degree relative
• Sudden death in a young family member
• Hyperlipidemia
• Diabetes mellitus

Signs of a Cardiac Disorder

• Cyanosis
• Irregular heart rate
• Edema
• Clubbing of fingertips
• Fever
• Retractions or increased work of breathing
• Prominence of precordial chest wall
• Visible, engorged, or abnormal pulsations
• Abdominal distention

Characteristics of Heart Murmurs

• Location on the chest where it's best heard is noted, as well as if it radiates elsewhere
• Relation to the heart cycle and duration is noted
• Quality: harsh, musical, or rough; high, medium, or low pitch
• Variation in sound with position (sitting, lying, standing)
• Intensity:
  • Grade I—soft and hard to hear
  • Grade II—soft and easily heard
  • Grade III—loud without thrill
  • Grade IV—loud with a precordial thrill
  • Grade V—loud with a precordial thrill, audible with a stethoscope partially off chest
  • Grade VI—very loud, audible with a stethoscope or with the naked ear

Focus of Nursing Care for a Child with a Cardiac Disorder

• Improving oxygenation
• Promoting adequate nutrition
• Assisting the child and family with coping
• Providing postoperative nursing care
• Preventing infection
• Providing child and family education

Relieving Hypercyanotic Spells

• Utilize a calm, comforting approach
• Place the infant or child in a knee-to-chest position
• Provide supplemental oxygen
• Administer morphine sulfate 0.1 mg/kg IV/IM/SQ, supply IV fluids and administer propranolol 0.1 mg/kg IV

Psychosocial Interventions

• Explain everything happening with the child, using language the parents and child can understand
• Allow parents/child to voice their feelings, concerns and questions
• Provide ample time to address questions and concerns
• Encourage the parents/child, as developmentally appropriate, to participate in the child’s care
• Encourage the child to be as active as appropriate

Parent Teaching for Cardiac Surgery

• Heart anatomy and its function
• Events before surgery
• Location of the child after surgery
• Appearance of the child after surgery
• Location of incision and coverage with dressings
• Postoperative activity level
• Nutritional restrictions
• Medications