Infant Respiratory Disorders: Types and Practice Questions

Infant respiratory disorders are a significant concern for newborns, especially those born prematurely or with underlying health conditions.

These disorders can range from mild to life-threatening, requiring immediate medical attention to ensure proper lung function and oxygenation. Conditions like NRDS, meconium aspiration syndrome, and apnea of prematurity are among the most common respiratory challenges faced by newborns.

This article provides an overview of the different types of infant respiratory disorders, their symptoms, and the available treatment options.

What is an Infant Respiratory Disorder?

An infant respiratory disorder refers to any condition that affects a newborn’s ability to breathe properly. These disorders can occur due to underdeveloped lungs, airway blockages, or complications during birth and are especially common in premature infants.

Examples include neonatal respiratory distress syndrome (NRDS), where a lack of surfactant makes it difficult for the lungs to expand, and meconium aspiration syndrome (MAS), caused by inhalation of meconium during delivery.

Infant respiratory disorders can lead to serious complications, requiring immediate medical intervention, such as oxygen therapy, mechanical ventilation, or other supportive treatments to ensure proper breathing and oxygenation.

Types of Infant Respiratory Disorders

Infant respiratory disorders are diverse and can affect newborns in various ways, particularly those born prematurely or with other complications.

Here are some of the primary types of respiratory disorders in infants:

• Neonatal respiratory distress syndrome (NRDS)
• Meconium aspiration syndrome
• Apnea of prematurity
• Congenital diaphragmatic hernia
• Delivery room management

Watch this video or keep reading to learn more about each type of infant respiratory disorder.

Neonatal Respiratory Distress Syndrome

Neonatal Respiratory Distress Syndrome (NRDS), also known as Hyaline Membrane Disease, primarily affects premature infants, particularly those born before 34 weeks of gestation. This condition occurs due to insufficient production of surfactant, a substance that helps keep the lungs inflated by reducing surface tension in the alveoli.

Without enough surfactant, the infant’s lungs have difficulty expanding, leading to breathing difficulties, rapid breathing, grunting, and low oxygen levels.

NRDS is a serious condition requiring prompt treatment, often including surfactant replacement therapy, mechanical ventilation, or oxygen therapy to support the infant’s breathing and improve lung function.

Meconium Aspiration Syndrome

Meconium Aspiration Syndrome (MAS) occurs when a newborn inhales a mixture of meconium (the baby’s first stool) and amniotic fluid into the lungs around the time of delivery. This can happen if the baby passes meconium while still in the womb due to stress or lack of oxygen.

Inhalation of meconium can block the infant’s airways and cause inflammation, leading to breathing difficulties, decreased oxygen levels, and, in severe cases, lung infections or pneumothorax.

Treatment may involve suctioning the airway, supplemental oxygen, and, in severe cases, mechanical ventilation to help the baby breathe more effectively.

Apnea of Prematurity

Apnea of Prematurity (AOP) is a common respiratory disorder affecting preterm infants, especially those born before 34 weeks of gestation. It is characterized by episodes where the infant stops breathing for 15 to 20 seconds or longer due to the underdevelopment of the brain’s respiratory control centers.

These pauses in breathing can lead to bradycardia (a slow heart rate), cyanosis (bluish skin color due to lack of oxygen), and a decrease in oxygen levels. AOP typically improves as the infant matures.

Treatment may include stimulating the baby during episodes, providing continuous positive airway pressure (CPAP), or using medications such as caffeine to stimulate the respiratory system.

Congenital Diaphragmatic Hernia

Congenital Diaphragmatic Hernia (CDH) is a birth defect where an abnormal opening in the diaphragm allows abdominal organs, such as the intestines, stomach, or liver, to move into the chest cavity.

This displacement prevents the lungs from developing fully, leading to underdeveloped or compressed lungs (pulmonary hypoplasia), which causes significant breathing difficulties at birth. CDH can result in life-threatening respiratory distress, requiring immediate medical intervention.

Treatment often includes mechanical ventilation, medications to stabilize the baby, and surgical repair to reposition the abdominal organs and close the diaphragm defect. In severe cases, extracorporeal membrane oxygenation (ECMO) may be used to support lung function temporarily while the baby stabilizes.

Delivery Room Management

Delivery room management involves the immediate care provided to newborns after birth, especially those at risk for or exhibiting signs of respiratory distress.

A critical part of this process is assessing the infant’s condition using the Apgar score, which evaluates heart rate, respiratory effort, muscle tone, reflex response, and skin color. For infants with conditions like neonatal respiratory distress syndrome (NRDS), meconium aspiration syndrome, or apnea of prematurity, early intervention is essential.

Key steps in management may include clearing the airway, providing warmth, administering oxygen or positive pressure ventilation, and closely monitoring vital signs. The goal is to stabilize the infant’s breathing and overall health as they transition to life outside the womb.

Infant Respiratory Disorders Practice Questions

1. What is Respiratory Distress Syndrome (RDS)?
Respiratory Distress Syndrome (RDS) is a condition affecting premature infants, caused by insufficient pulmonary surfactant, leading to widespread atelectasis and hypoxemia.

2. What are the symptoms of RDS?
Symptoms of RDS include nasal flaring, grunting, retractions, tachypnea, cyanosis, hypercapnia, and hypoxemia.

3. What is RDS also known as?
RDS is also known as Hyaline Membrane Disease (HMD).

4. What is Bronchopulmonary Dysplasia (BPD)?
Bronchopulmonary Dysplasia (BPD) is a chronic lung disease in infants who have experienced severe RDS, often after prolonged positive pressure ventilation and oxygen therapy.

5. What is Transient Tachypnea of the Newborn (TTN)?
TTN is delayed clearance of fetal lung fluid, typically resolving with minimal intervention. It is also called RDS Type II or “Wet Lung Syndrome,” and it involves persistent postnatal pulmonary edema, more common in full-term infants.

6. What is neonatal pneumonia?
Neonatal pneumonia is a leading cause of respiratory infection-related deaths in newborns, responsible for about 800,000 deaths worldwide, affecting 10% of NICU infants, with a higher prevalence in preterm babies.

7. What are the risk factors of neonatal pneumonia?
Risk factors for neonatal pneumonia include low socioeconomic status, teenage mothers, sexually active mothers, and maternal infections.

8. What are the causative organisms for neonatal pneumonia?
Common organisms include Group B Streptococcus (GBS), Escherichia coli, Klebsiella, Listeria, Staphylococcus, Pseudomonas, Chlamydia trachomatis, and pathogens from Torch syndrome (toxoplasmosis, rubella, cytomegalovirus, and herpes).

9. What is Meconium Aspiration Syndrome (MAS)?
Meconium Aspiration Syndrome (MAS) primarily affects newborns, where meconium is present in the lungs due to inhalation of meconium-stained amniotic fluid (MSAF) during birth.

10. What is Persistent Pulmonary Hypertension (PPHN)?
Persistent Pulmonary Hypertension of the Newborn (PPHN) is a syndrome where normal circulatory transition from fetal to neonatal life is disrupted, also referred to as persistent fetal circulation.

11. What is Apnea of Prematurity (AOP)?
Apnea of Prematurity (AOP) is the sudden cessation of breathing for at least 20 seconds, often accompanied by bradycardia or cyanosis in infants born before 37 weeks gestation.

12. What are the Air Leak Syndromes?
Air Leak Syndromes include pulmonary interstitial emphysema, pneumothorax, pneumomediastinum, pneumopericardium, pneumoperitoneum, subcutaneous emphysema, and systemic air embolism.

13. How do you get the diagnosis of air leak syndromes?
Air leak syndromes are diagnosed through chest X-ray, transillumination, needle aspiration of air (for air embolism), arterial blood gases (ABGs), and ECG.

14. What can increase the risk of RDS?
Risk factors for RDS include maternal diabetes, multiple births, cesarean delivery, and fetal asphyxia, with males being slightly more susceptible.

15. When does Respiratory Distress Syndrome typically occur?
RDS occurs in 60-80% of infants born before 28 weeks gestation.

16. What is the etiology and pathophysiology of RDS?
In infants born before 28 weeks, underdeveloped alveoli and a lack of surfactant lead to atelectasis, decreased functional residual capacity (FRC), and reduced compliance. This results in hypoxia, hypercapnia, and respiratory acidosis.

17. What are the signs of RDS?
Signs of RDS include tachypnea, grunting, nasal flaring, retractions, diminished breath sounds, progressive cyanosis, unresponsive to oxygen therapy, and hypotonia or unresponsiveness.

18. What are the ABG results in RDS?
Arterial blood gas (ABG) results in RDS show moderate to severe hypoxemia, hypercapnia, and mixed acidosis.

19. What will a chest x-ray show in RDS?
A chest x-ray in RDS will reveal diffuse granular opacities and a ground-glass appearance.

20. How can we help prevent RDS?
Preventive measures for RDS include managing high-risk pregnancies to avoid preterm birth, avoiding poorly timed cesarean sections, preventing asphyxia through antenatal and intrapartum fetal monitoring, proper resuscitation techniques, and antenatal steroid therapy.

21. What is the treatment for RDS?
Treatment for RDS includes surfactant replacement and oxygen therapy, which is heated, humidified, and blended to provide precise FiO2 titration, monitored by blood gas analysis and pulse oximetry. According to the OWL protocol, nasal CPAP is indicated if oxygen saturation is <85% at FiO2 of 40-70%. An NG tube is also used for swallowed air.

22. When is mechanical ventilation indicated for the treatment of RDS?
Mechanical ventilation is indicated when there is respiratory failure or apnea, particularly if pH is <7.20, PaCO2 >60, or PaO2 <85%.

23. What are the four risk factors of bronchopulmonary dysplasia?
Risk factors for bronchopulmonary dysplasia (BPD) include: 1) Prematurity, related to gestational age, birth weight, and incomplete lung development. 2) Respiratory failure. 3) Hypoxia/hyperoxia-induced lung injury, especially in infants with frequent hypoxic episodes, as preterm infants have fewer antioxidants. 4) Ventilator-induced lung injury from volutrauma and increased PIP, triggering an inflammatory cascade.

24. What is the treatment for BPD?
Treatment for BPD involves minimizing further lung injury, optimizing nutrition, and reducing oxygen consumption. Fluid management should be conservative, using diuretics when necessary. Maintain normal hemoglobin levels (with transfusions if needed). Drug therapies include bronchodilators, methylxanthines, steroids (controversial), GERD medications, and pulmonary vasodilators. Nutrition is provided enterally or parenterally.

25. What is another name for transient tachypnea of the newborn?
Another name for transient tachypnea of the newborn (TTN) is “Wet Lung Syndrome.”

26. What is the incidence of transient tachypnea of the newborn?
TTN is more common in infants born via cesarean section and in full-term infants.

27. What is the treatment for TTN?
Treatment for TTN includes maintaining adequate oxygenation and ventilation, oxygen therapy, and nasal CPAP. Antibiotics are also administered to treat any underlying infection.

28. What is the incidence of neonatal pneumonia?
Neonatal pneumonia occurs in approximately 10% of infants in NICUs, with higher incidence in lower socioeconomic groups, teenage mothers, and sexually active mothers.

29. What are the modes of transmission for neonatal pneumonia?
Neonatal pneumonia can be transmitted via transplacental, ascending vertical transmission (from the genital tract before or during birth, often associated with PROM), or postnatally through exposure to infectious agents from people, breast milk, or contaminated objects.

30. What are the risk factors for neonatal pneumonia?
Risk factors include prematurity, low birth weight (LBW), pre-labor rupture of membranes (PROM), maternal peripartum infection, and meconium aspiration.

31. What are the respiratory symptoms of neonatal pneumonia?
Respiratory symptoms include grunting, tachypnea, retractions, nasal flaring, cyanosis, apnea, and respiratory failure.

32. How can we help with the prevention of neonatal pneumonia?
Prevention of neonatal pneumonia includes strict adherence to universal precautions, maintaining a low nurse-to-patient ratio, reducing blood sampling and ventilator days, optimizing enteral feeding practices, and enforcing proper hand hygiene.

33. What is the treatment of neonatal pneumonia?
Treatment includes appropriate anti-infective agents, oxygen, ventilatory support, maintaining airway patency, and continuous monitoring. Pharmacotherapy involves broad-spectrum antibiotics pending culture results, and extracorporeal membrane oxygenation (ECMO) is considered when conventional therapy fails.

34. What is Respiratory Distress Syndrome (RDS)?
RDS is an acute condition in newborns characterized by atelectasis, poor lung compliance, surfactant deficiency, tachypnea, peripheral edema, and inflammation.

35. What is the incidence of RDS?
RDS affects approximately 1% of infants born in the US. It is the leading cause of death in premature infants, affecting 10% of preterm infants, with a 10% mortality rate in those cases. It has a higher incidence in infants with very low birth weight.

36. What are the risk factors of RDS?
Risk factors for RDS include prematurity, maternal diabetes, hypothermia, fetal distress, male sex, second-born twins, cesarean delivery without labor, and a history of a previous child with RDS.

37. What is the pathophysiology of RDS?
RDS is caused by insufficient surfactant production. The lack of surfactant leads to atelectasis and “see-saw” breathing, resulting in decreased lung compliance, hypoxia, hypercapnia, and respiratory acidosis.

38. What is the clinical presentation of RDS?
Clinical presentation includes preterm birth, tachypnea, increased work of breathing (WOB), cyanosis, grunting, nasal flaring, see-saw breathing, and an enlarged heart in some cases.

39. What will the ABG results show for RDS?
ABG results for RDS typically show moderate to severe hypoxemia, hypercapnia, and mixed acidosis.

40. How to help with the prevention of RDS?
Prevention includes delaying delivery and administering maternal steroids at least 48 hours before birth to accelerate fetal lung maturity.

41. What is surfactant therapy?
Surfactant therapy, often combined with steroids, can reduce the duration of mechanical ventilation and lessen the severity of bronchopulmonary dysplasia (BPD) if it develops.

42. When is mechanical ventilation indicated for RDS?
Mechanical ventilation is indicated if pH < 7.20, PaCO2 > 60, oxygen saturation < 85% at FiO2 of 40-60%, and CPAP of 5-10 cm H2O. For very low birth weight infants (<1000g), intubation may be required at delivery.

43. What are the complications of RDS?
Complications of RDS include bronchopulmonary dysplasia (BPD), chronic lung disease, reactive airway disease, pneumothorax, and intraventricular hemorrhage.

44. What is retinopathy of prematurity?
Retinopathy of prematurity (ROP) can result in retinal scarring, tearing, detachment, and blindness. It is associated with hyperoxia, which stimulates abnormal vascular endothelial growth factor production.

45. What is transient tachypnea of the newborn?
Transient tachypnea of the newborn (TTN) is a benign condition in near-term or term infants characterized by respiratory distress that typically resolves within 72 hours (often 24-48). It is also known as “wet lung” or RDS type 2.

46. What is the pathophysiology of transient tachypnea of the newborn?
TTN is thought to result from delayed reabsorption of fetal lung fluid, leading to decreased lung compliance, reduced tidal volume, and increased dead space.

47. What will the chest x-ray show for transient tachypnea of the newborn?
A chest x-ray in TTN typically shows pulmonary vascular congestion, perihilar streaking, hyperinflation, and flat diaphragms.

48. What is the treatment for transient tachypnea of the newborn?
Treatment includes oxygen therapy, CPAP, and intubation in severe cases. Feeding should be withheld if the respiratory rate is >60. Symptoms usually resolve in 12-24 hours, and the infant is typically off oxygen within 48 hours.

49. What is Meconium Aspiration Syndrome?
Meconium Aspiration Syndrome (MAS) occurs when meconium is present in the tracheobronchial airways below the vocal cords.

50. How often does Meconium Aspiration Syndrome occur?
Meconium staining occurs in 10-15% of deliveries.

51. What is the clinical presentation of Meconium Aspiration Syndrome?
Infants with MAS are typically term or post-term, may have meconium staining, low APGAR scores, rapid onset of respiratory distress, diminished breath sounds, rales, and an increased AP diameter.

52. What will the chest x-ray show for Meconium Aspiration Syndrome?
A chest x-ray in MAS reveals patchy atelectasis, hyper-expansion, opacity in severe cases, and findings similar to bacterial pneumonia.

53. What is the treatment for Meconium Aspiration Syndrome?
Treatment includes suctioning, oxygen therapy, and mechanical ventilation.

54. What are the complications of Meconium Aspiration Syndrome?
Complications include barotrauma, air leaks, increased intracranial pressure (ICP), and bronchopulmonary dysplasia.

55. What is neonatal apnea?
Neonatal apnea is defined as the cessation of breathing for >20 seconds or any pause in breathing long enough to cause bradycardia, cyanosis, or both in an infant younger than 37 weeks gestation.

56. What is the clinical presentation of neonatal apnea?
Neonatal apnea presents with apnea, bradycardia, snoring or choking, loss of muscle tone, and cyanosis.

57. What is the treatment for neonatal apnea?
Treatment includes monitoring, CPAP, bag-mask ventilation, caffeine therapy, and avoiding factors that can trigger apnea.

58. What are the complications of neonatal apnea?
Complications include the need for infants to be discharged with an apnea monitor. The condition typically resolves by 36 weeks gestation, depending on the cause.

59. What is Wilson-Mikity Syndrome?
Wilson-Mikity Syndrome involves mild respiratory distress in the first few days of life, but after a period of apparent recovery, tachypnea and cyanosis return 1-5 weeks later.

60. What is Chronic Pulmonary Insufficiency of Prematurity (CPIP)?
CPIP refers to a condition in which premature infants partially recover from RDS but later require oxygen supplementation due to episodes of apnea.

61. What is Bronchopulmonary Dysplasia?
Bronchopulmonary Dysplasia (BPD) is a chronic lung disorder that primarily affects infants born prematurely, especially those requiring prolonged oxygen therapy or mechanical ventilation.

62. What are the three types of Bronchopulmonary Dysplasia?
The three types of BPD are mild, moderate, and severe.

63. What is mild Bronchopulmonary Dysplasia?
Mild BPD is when infants are able to breathe room air without requiring supplemental oxygen.

64. What is moderate Bronchopulmonary Dysplasia?
Moderate BPD is characterized by infants needing less than 30% supplemental oxygen.

65. What is severe Bronchopulmonary Dysplasia?
Severe BPD is when infants require more than 30% supplemental oxygen to maintain adequate oxygenation.

66. What is the incidence of Bronchopulmonary Dysplasia?
BPD occurs in 15-50% of infants weighing less than 1500 grams, with the risk increasing the earlier the infant is born.

67. What is the pathophysiology of Bronchopulmonary Dysplasia?
BPD develops due to a combination of lung immaturity, respiratory failure, positive pressure ventilation (PPV), inflammation, nutritional deficiencies, and genetic predisposition.

68. What is the treatment for Bronchopulmonary Dysplasia?
Treatment includes surfactant therapy to improve survival, CPAP, using low tidal volumes and short inspiratory times on a ventilator, ECMO, high-frequency ventilation (HFV), proper nutrition, permissive hypercapnia, steroids, caffeine, bronchodilators, diuretics, and pulmonary vasodilators.

69. What are the complications of Bronchopulmonary Dysplasia?
Complications include increased susceptibility to airway infections, exercise intolerance, reactive airway disease, tonsillar and adenoidal hypertrophy, vocal cord paralysis, and subglottic stenosis.

70. What are the long-term side effects of Bronchopulmonary Dysplasia?
Long-term effects of BPD include pulmonary hypertension, cor pulmonale, systemic hypertension, and neurological deficits.

71. What is Persistent Pulmonary Hypertension of the Newborn (PPHN)?
PPHN is characterized by systemic arterial hypoxemia due to elevated pulmonary vascular resistance, leading to right-to-left shunting and alterations in pulmonary vasoreactivity.

72. What is the incidence of PPHN?
PPHN is rare, occurring in 1 to 2 per 1,000 births, and is more common in full-term and post-term infants. It carries a high risk of mortality.

73. What are the primary causes of PPHN?
Primary causes of PPHN include anatomic malformations, genetic factors, and chronic prenatal stress.

74. What are the secondary causes of PPHN?
Secondary causes include Meconium Aspiration Syndrome (MAS), congenital heart disease, infections, and upper airway obstructions.

75. What is the clinical presentation of PPHN?
Clinical presentation includes cyanosis, tachypnea, respiratory distress (retractions, grunting, nasal flaring), and cardiomegaly. Chest x-rays may appear clear in early stages but show hyperinflation in later stages.

76. What is the treatment of PPHN?
Treatment includes maintaining stable laboratory values, minimizing handling and noise, mechanical ventilation, mild hyperventilation for 12-24 hours, high-frequency ventilation (HFV), extracorporeal membrane oxygenation (ECMO), sedation with fentanyl, nitric oxide therapy, and intravenous magnesium.

77. What are the complications of PPHN?
Complications include a mortality rate of around 40%, with a survival rate of 20% with ECMO or inhaled nitric oxide (iNO), and neurological disabilities affecting 15-60% of survivors.

78. What is Air Leak Syndrome?
Air Leak Syndrome refers to any condition in which air escapes from the lungs through abnormal routes, outside the normal pathways.

79. What is the incidence of Air Leak Syndrome?
Air Leak Syndrome occurs more frequently in preterm infants and in those with conditions such as RDS, MAS, and pulmonary hypoplasia.

80. What are the causes of Air Leak Syndrome?
Causes of Air Leak Syndrome include over-distension of the lungs, uneven alveolar ventilation, and air trapping.

Final Thoughts

Infant respiratory disorders present unique challenges, but advances in medical technology and neonatal care have improved outcomes significantly.

Early diagnosis and treatment, along with comprehensive delivery room management, can help stabilize newborns experiencing respiratory difficulties.

By increasing awareness and knowledge about these conditions, we can better support the health and development of infants during their critical early stages of life.