Pediatric Cardiovascular 2025

Pediatric Cardiovascular

Fetal Development

  • Nutrient and Waste Exchange

    • Occurs through the placenta

  • Circulation

    • Umbilical vein carries oxygenated blood from the placenta via the ductus venosus to the inferior vena cava.

    • Small amount of blood enters the right ventricle; major blood flow enters the left atrium through the foramen ovale.

    • Majority of blood that enters the right ventricle bypasses the lungs via the ductus arteriosus to the descending aorta.

    • Blood to the lungs only supplies lung cells.

    • Most blood passes from right atrium to left atrium, then to left ventricle for distribution to the body.

    • The descending aorta carries blood to the umbilical arteries, returning to the placenta for waste removal and nutrient uptake.

Fetal Circulation Diagram

  • Anatomy involved

    • Superior vena cava, right pulmonary artery, ductus arteriosus, aorta, left pulmonary artery, left pulmonary vein, foramen ovale, inferior vena cava, ductus venosus, and umbilical vessels.

Fetal Development (Continued)

  • Heart Rate: 120-160 bpm

  • Oxygen Saturation: 80%

  • Placental Pressure Gradient: Allows rapid diffusion of carbon dioxide.

Fetal Hemoglobin

  • Composition: 2 alpha and 2 gamma chains

  • Affinity: Greater oxygen affinity than adult hemoglobin.

  • Newborn Hemoglobin Levels: 17.1 g/dL vs. 12 g/dL (adult average).

  • Newborn Hematocrit: 53% vs. 45% (adult average).

  • Development: Changes continue until about 6 months after birth.

After Birth Changes

  • Lungs Expand

  • Increased Oxygen

    • Causes pulmonary vasodilation.

    • Decreased pulmonary pressure as systemic pressure increases.

  • Closure of Structures

    • Foramen ovale closes.

    • Ductus arteriosus closure initiates with increased oxygen concentration.

    • Clamping of the umbilical cord ceases blood flow driving closure of the ductus venosus.

Risk Factors for Pediatric Cardiovascular Problems

  • Family History: Heart disease.

  • Intrauterine Exposure: Teratogens, diseases, prenatal nutrition, radiation, drugs, and toxins.

  • Other Factors: Autoimmune responses, hypertension, obesity, inactivity increase disorder risk.

Physical Assessment

  • General

    • Measure height and weight (child preferably relaxed).

  • Cyanosis Assessment

    • Inspect buccal membranes/lips for changes.

    • Central cyanosis persisting beyond 20 mins post-birth indicates potential dysfunction.

    • Observe variations between cyanosis worsening or improving with crying.

  • Clinical Signs

    • Clubbing, capillary refill, complexion, lethargy, increased respirations, heart movement visibility in left chest, tachycardia (infants > 160, children > 100).

Murmur Assessment

  • Characterization of Murmurs

    • Position in cardiac cycle, duration, quality, pitch, intensity (grade I-VI), location, and any accompanying thrills.

  • Types of Murmurs

    • Innocent Murmur: No clinical significance, normal variation, no follow-up or activity restrictions needed.

    • Pathologic Murmur: Indicative of heart disease or congenital defects.

Location of Murmurs

  • Areas and Expected Findings:

    • Aortic Area: Ejection-type (e.g. aortic stenosis, flow murmur).

    • Pulmonic Area: Ejection-type (e.g. pulmonic stenosis, flow murmur).

    • Tricuspid Area: Pansystolic murmur (e.g. tricuspid regurgitation, ventricular septal defect).

    • Mitral Area: Pansystolic murmur (e.g. mitral regurgitation, mid-late diastolic murmur).

Diagnostic Techniques

  • Laboratory Studies

    • Patient history, medication list, no food/fluid restrictions required.

    • Assure child understanding of procedure, emphasize stillness, and observe post-draw.

  • Diagnostic Testing

    • Includes blood chemistries, hematology assessments, and ESR test.

Arterial Blood Gas (ABG)

  • Purpose: Assess acid-base balance and respiratory function.

  • Procedural Steps

    • Allen’s test if radial artery is used; may require anesthesia.

    • Pressure must be applied longer than for venous draws.

  • pH and Gases Reference Ranges:

    • Newborn pH: 7.11-7.36, Child pH: 7.35-7.45.

6 Easy Steps to ABG Analysis

  1. Check pH for range.

  2. Evaluate pCO2 levels.

  3. Review HCO3 level.

  4. Match abnormal result with pH.

  5. Determine compensation by direction of pCO2 or HCO3 relative to pH.

  6. Assess pO2 and O2 saturation for anomalies.

Cardiac Catheterization

  • Purpose: Evaluate cardiac abnormalities, cardiac output, and blood flow pressures.

  • Pre-operative Requirements

    • Chest X-ray, EKG, and necessary studies conducted.

    • Ensure emergency equipment is accessible.

  • Post-procedure Care

    • Monitor for bleeding, thrombophlebitis, infection, and vital signs.

Electrocardiogram (EKG/ECG)

  • Purpose: Measure heart electrical impulses.

  • Diagnosis: Used to detect arrhythmias, imbalances, and anoxia.

  • Key Components

    • P wave: Atrial depolarization, QRS: Ventricular depolarization, ST segment: baseline alignment, T wave: Ventricular repolarization.

Echocardiogram

  • Process: High-frequency sound waves visualize cardiac structures.

  • Evaluation: Assess chambers, thickness, valve flow, directionality, and can check intrauterine heart development.

  • Patient Education: Remain still, may require sips of vasodilators, and contrast media may be used.

Fluoroscopy

  • Technique: Use of radioactive substances to trace blood flow.

  • Considerations: Educate risks of radiation and emphasize lying still.

Nursing Assessment

  • Subjective Information: Family history, past and current health histories.

  • Objective Measures: Inspection, palpation, percussion; assess overall cardiovascular health and developmental indicators.

Cardiovascular Problems

  • Congenital Heart Disease

    • Anatomic abnormalities present at birth with resultant CHF and hypoxemia; may be single-gene or multifactorial conditions.

  • Acquired Cardiac Disorders

    • Processes occurring after birth affected by environment, infection, and familial factors.

Congenital Heart Disease Classifications

  • Cyanotic vs. Acyanotic:

    • Acyanotic: Left-to-right shunt, normal oxygenation in systemic circulation.

    • Cyanotic: Right-to-left shunt leading to desaturation and associated complications.

Examples of Congenital Heart Defects

  • Atrial Septal Defect, Ventricular Septal Defect, Patent Ductus Arteriosus, and various obstructions such as aortic stenosis and coarctation of the aorta.

Management of Specific Defects

  • Atrial Septal Defect: Potential surgical intervention, monitoring, and education on risks.

  • Ventricular Septal Defect: Often resolves but requires monitoring and potential surgical repair.

  • Patent Ductus Arteriosus: May require medication or surgery; monitor for complications.

Pediatric Heart Failure Management

  • Symptoms: Tachypnea, poor weight gain, edema, fatigue, and 3rd heart sound presence.

  • Management Strategies: Oxygen support, ACE inhibitors, fluid management; emphasize education on compliance and monitoring symptoms.

Kawasaki Disease

  • Description: Mucocutaneous lymph node syndrome with potential cardiovascular impacts.

  • Diagnosis: Requires persistent fever and relevant features like conjunctivitis and lymphadenopathy.

Rheumatic Fever

  • Description: Inflammatory disease often following a streptococcal infection, with significant potential cardiac implications.

  • Management: Focus on treating underlying infections and preventing recurrence, along with ongoing follow-up for cardiac health.

Pediatric Cardiovascular Overview

Fetal Development

  • Nutrient and Waste Exchange: This essential function occurs through the placenta, facilitating the transfer of oxygen and nutrients to the fetus.

Circulation During Fetal Development

  • Umbilical Vein: Carries oxygenated blood from the placenta via the ductus venosus to the inferior vena cava, playing a crucial role in fetal circulation.

  • Blood Flow Distributions:

    • A small amount of blood enters the right ventricle; however, the majority flows into the left atrium through the foramen ovale, bypassing the lungs, which are non-functional in utero.

    • Blood entering the right ventricle typically bypasses the lungs via the ductus arteriosus to the descending aorta, essentially providing oxygen to the body's essential organs, while blood flow to the lungs primarily aims to supply lung cells.

  • Majority of Blood Flow: Blood is directed from the right atrium to the left atrium, then to the left ventricle, enabling systematic distribution throughout the body.

  • Return Pathway: The descending aorta carries blood to the umbilical arteries, which transport deoxygenated blood back to the placenta for nutrient uptake and waste removal.

Fetal Circulation Diagram Anatomy

Key Structures Involved

  • This system involves various anatomical structures, including:

    • Superior vena cava

    • Right & left pulmonary arteries

    • Ductus arteriosus

    • Aorta

    • Left pulmonary vein

    • Foramen ovale

    • Inferior vena cava

    • Ductus venosus

    • Umbilical vessels

Fetal Development Vital Statistics

  • Heart Rate: Typically ranges between 120-160 bpm.

  • Oxygen Saturation Levels: Approximately 80% during fetal development.

  • Placental Pressure Gradient: This gradient is significant as it allows the rapid diffusion of carbon dioxide away from the fetus, maintaining homeostasis.

Fetal Hemoglobin Characteristics

  • Composition: Comprises two alpha and two gamma chains, distinguishing it from adult hemoglobin.

  • Oxygen Affinity: Fetal hemoglobin binds oxygen more readily, which is vital for fetal survival in a low-oxygen environment.

  • Newborn Hemoglobin Levels: Typically 17.1 g/dL, compared to the adult average of 12 g/dL.

  • Hematocrit Levels: Newborns typically have a hematocrit of 53%, while adults average 45%.

  • Developmental Changes: Hemoglobin composition starts changing until approximately six months after birth, transitioning toward adult levels.

Changes After Birth

  1. Lungs Expand: At birth, the lungs expand, marking the onset of effective respiration.

  2. Increased Oxygen Levels: The introduction of oxygen leads to pulmonary vasodilation, crucial for managing blood flow through newly functional pulmonary circulation.

  3. Decreased Pulmonary Pressure: As systemic pressure increases, pulmonary pressure decreases, allowing blood flow dynamics to shift accordingly.

Closure of Fetal Circulatory Structures

  • Foramen Ovale: Closes after birth due to increased left atrial pressure.

  • Ductus Arteriosus: Closes with increased oxygen levels post-delivery, ceasing the bypass of pulmonary circulation.

  • Ductus Venosus Closure: Clamping of the umbilical cord stops blood flow, subsequently leading to the closure of this vessel.

Risk Factors for Pediatric Cardiovascular Issues

  • Family History: A significant predisposition exists for children with a family history of heart disease.

  • Intrauterine Exposure: Exposure to teratogens, infections, poor prenatal nutrition, radiation, certain drugs, and toxins can adversely affect fetal heart development.

  • Other Contributing Factors: Autoimmune responses, hypertension, obesity, and lack of physical activity are linked to higher risks of developing cardiovascular disorders.

Physical Assessment in Pediatric Patients

General Considerations

  • Measurement: Height and weight should be measured with the child relaxed to ensure accuracy.

  • Cyanosis Assessment: Inspect buccal membranes and lips; persistent central cyanosis beyond 20 minutes post-birth can indicate significant dysfunction.

  • Observation: Monitor variations in cyanosis, noting whether it worsens or improves with crying.

Clinical Signs to Observe

  • Signs of distress: Look for clubbing, capillary refill rates, complexion changes, lethargy, increased respirations, visible heart movements in the left chest, and tachycardia (infants > 160 bpm, children > 100 bpm).

Murmur Assessment

Characterization of Murmurs

  • Murmurs should be characterized by their:

    • Position within the cardiac cycle

    • Duration

    • Quality

    • Pitch

    • Intensity (graded I-VI)

    • Location

    • Any accompanying thrills

Types of Murmurs

  • Innocent Murmur: Lacks clinical significance, considered a normal physiological variation; no follow-up or activity restrictions necessary.

  • Pathologic Murmur: Suggestive of heart disease or congenital defects necessitating further investigation.

Locations and Expected Findings of Heart Murmurs

  • Aortic Area: May reveal ejection-type murmurs indicative of aortic stenosis or flow murmurs.

  • Pulmonic Area: Similarly, may display ejection-type murmurs suggestive of pulmonic stenosis or related conditions.

  • Tricuspid Area: Generally presents pansystolic murmurs, possibly seen in tricuspid regurgitation or ventricular septal defects.

  • Mitral Area: Pansystolic murmurs may indicate mitral regurgitation or mid-late diastolic murmurs, depending on the underlying pathology.

Diagnostic Techniques

Laboratory Studies

  • Requires detailed patient history and a current medication list, with no food or fluid restrictions necessary for the child.

  • Provide thorough explanations to the child regarding procedures, emphasizing the importance of remaining still and monitor the site post-draw.

Diagnostic Testing Overview

  • Consists of blood chemistries, hematology assessments, and Erythrocyte Sedimentation Rate (ESR) tests as necessary.

Arterial Blood Gas (ABG) Assessment

  • Purpose: Evaluation of acid-base balance and respiratory function critical in pediatric patients, particularly those with existing cardiac troubles.

  • Procedural Steps: Allen’s test may be required when accessing the radial artery; extend the pressure application beyond venous draws.

  • pH and Gas Reference Ranges:

    • Newborn pH: 7.11-7.36

    • Child pH: 7.35-7.45

6 Easy Steps to ABG Analysis

  1. Check pH: Ensure it falls within normal ranges.

  2. Evaluate pCO2 Levels: Analyze arterial carbon dioxide levels for abnormalities.

  3. Review HCO3 Level: Determine the presence of bicarbonate levels to assess metabolic status.

  4. Match Abnormal Results with pH: Correlate results to ascertain underlying conditions.

  5. Determine Compensation Mechanisms: Identify how pCO2 or HCO3 levels adjust in response to pH imbalances.

  6. Assess pO2 and O2 Saturation: Look for anomalies that may indicate respiratory distress.

Cardiac Catheterization Overview

  • Purpose: Used to evaluate cardiac anomalies, assess cardiac output, and measure blood flow pressures.

  • Pre-operative Requirements: Ensure a chest X-ray, EKG, and any additional necessary tests have been completed, with emergency equipment readily available.

  • Post-procedure Care: Vigilance for complications such as bleeding, thrombophlebitis, infections, and monitoring vital signs post-procedure is critical.

Electrocardiogram (EKG/ECG)

  • Purpose: Measures the electrical impulses of the heart, crucial for the diagnosis of arrhythmias, imbalances, and potential anoxic events.

  • Key Components:

    • P wave: Indicates atrial depolarization

    • QRS: Reflects ventricular depolarization

    • ST Segment: Should align with the baseline

    • T wave: Represents ventricular repolarization

Echocardiogram Overview

  • Process: Utilizes high-frequency sound waves to visualize cardiac structures and blood flow dynamics.

  • Evaluation Aspects: Assess the size of heart chambers, wall thickness, valve function, flow direction, and also permits evaluation of intrauterine heart development.

  • Patient Education: Stress the need to remain still, discuss the potential for vasodilator sips, and possible use of contrast media.

Fluoroscopy in Cardiac Care

  • Technique: Employs radioactive materials to trace blood flow, essential for thorough cardiac assessments.

  • Considerations: Provide education regarding radiation exposure risks and emphasize the importance of remaining still during the procedure.

Nursing Assessment Approach

  • Subjective Information: Gather detailed family history and relevant past and current health histories.

  • Objective Measures: Conduct a thorough assessment via inspection, palpation, percussion, and evaluate overall cardiovascular health alongside developmental indicators.

Understanding Cardiovascular Problems

Congenital Heart Disease

  • Defined by anatomical abnormalities present at birth that lead to congestive heart failure (CHF) and hypoxemia; can arise from genetic factors or multifactorial influences.

Acquired Cardiac Disorders

  • Disorders that emerge after birth influenced by environmental factors, infections, or hereditary traits.

Congenital Heart Disease Classifications

  • Cyanotic vs. Acyanotic:

    • Acyanotic: Conditions that create a left-to-right shunt, maintaining normal oxygenation in systemic circulation levels.

    • Cyanotic: Conditions that involve a right-to-left shunt, leading to systemic desaturation and increased complication risks.

Examples of Congenital Heart Defects

  1. Atrial Septal Defect

  2. Ventricular Septal Defect

  3. Patent Ductus Arteriosus

  4. Various obstructive lesions associated with aortic stenosis and coarctation of the aorta.

Management of Specific Defects

  • Atrial Septal Defect: May necessitate surgical intervention, along with careful monitoring and education related to associated risks.

  • Ventricular Septal Defect: Often resolves on its own but needs ongoing observation and may require surgical management if complications arise.

  • Patent Ductus Arteriosus: May require pharmacological interventions or surgical correction; close monitoring for complications is imperative.

Pediatric Heart Failure Management Strategies

  • Common Symptoms: These include tachypnea, inadequate weight gain, edema, fatigue, and the presence of a third heart sound.

  • Management Approaches: Involve oxygen support, administration of ACE inhibitors, careful fluid management, and emphasizing educational strategies on compliance and symptom monitoring.

Kawasaki Disease

  • Description: A significant mucocutaneous lymph node syndrome that can potentially impact the cardiovascular system, particularly affecting coronary arteries.

  • Diagnosis Criteria: Diagnosis requires a persistent fever lasting more than five days alongside other clinical findings, including conjunctivitis, lymphadenopathy, and rashes.

Rheumatic Fever Overview

  • Description: An inflammatory condition that typically follows a streptococcal infection, carrying significant risks for cardiac implications lasting throughout life.

  • Management Focus: Aims to treat the underlying streptococcal infection, prevent disease recurrence, and ensure ongoing clinical follow-up for cardiac health monitoring.