Common Neonatal Respiratory Disorders: RDS and TTN

Neonatal and Pediatric Respiratory Disorders

An analysis of common respiratory conditions affecting newborns, including Respiratory Distress Syndrome (RDS), Transient Tachypnea of the Newborn (TTN), Meconium Aspiration Syndrome (MAS), Bronchopulmonary Dysplasia (BPD), Apnea of Prematurity, Congenital Diaphragmatic Hernia, and Congenital Heart Disease.

Respiratory Distress Syndrome (RDS)

RDS, also called hyaline membrane disease, is related to prematurity. The incidence increases with decreasing gestational age in the infant.

Major Factors in Pathophysiology

• Qualitative surfactant deficiency
• Decreased alveolar surface area
• Increased small airway compliance
• Presence of the ductus arteriosus

Clinical Manifestations

• Tachypnea
• Worsening retractions
• Paradoxical breathing
• Audible grunting and nasal flaring
• Fine inspiratory crackles
• Cyanosis

Definitive Diagnosis

A definitive diagnosis is made via chest radiography, which shows diffuse, hazy, reticulogranular densities with the presence of air bronchograms and low lung volumes.

Treatment

Initial treatment often involves CPAP and PEEP. Other interventions include:

• Surfactant Replacement and HFV: Mechanical ventilation is used if oxygenation does not improve with CPAP and a given FiO2, or if the patient is apneic or acidotic.
• Minimization of Volutrauma: The PIP should be kept less than 30 cm H2O for larger premature infants and even lower for more immature infants.
• Three Surfactant Preparations: Beractant, Calfactant, and Poractant Alfa.

Transient Tachypnea of the Newborn (TTN)

TTN is the most common respiratory disorder of the newborn. The most probable etiology is the delayed clearance of fetal lung liquid, especially in infants born by cesarean section, preterm, or who are small for their gestational age. Mothers of neonates who have TTN tend to have longer labor intervals and a higher incidence of failure to progress in labor.

Clinical Manifestations and Diagnosis

• Tachypnea is a primary sign, while pH and PCO2 levels are typically normal.
• A chest X-ray may show hyperinflation secondary to air trapping, perihilar streaking, and pleural effusions in the costophrenic angles and interlobar fissures.

Treatment

• Oxygen Therapy: A low FiO2 is administered by oxyhood or nasal cannula. Infants requiring a higher FiO2 may benefit from CPAP.
• Antibiotics: Intravenous administration of antibiotics should be considered for at least 3 days after appropriate cultured samples are obtained.

Clinical and radiographic clearing of the lungs usually occurs within 24 to 48 hours.