para>A disorder of the neonatal period
EPIDEMIOLOGY
Incidence
- Predominant age: 93% incidence in infants born at or before 28 weeks ' gestational age
- Inversely proportional to gestational age and birth weight
- Predominant sex: slight male predominance
- Eighth leading cause of infant death in United States in 2013: 13.3 infant deaths per 100,000 live births (1)
- Despite advances, survival of infants born before 25 weeks ' gestation is rare (2).
Prevalence
Common disorder in premature infants, especially those born <28 weeks ' gestation
ETIOLOGY AND PATHOPHYSIOLOGY
- Structurally immature lungs and surfactant deficiency lead to diffuse atelectasis.
- Exposure to high FiO2 and barotrauma associated with mechanical ventilation trigger proinflammatory cytokines that further damage alveolar epithelium.
- Decreased lung compliance leads to alveolar hypoventilation and ventilation " perfusion mismatch.
- Impaired surfactant synthesis and secretion
Genetics
No known genetic pattern
RISK FACTORS
- Premature birth
- Infants of diabetic mothers
- Perinatal asphyxia
- History of RDS in a sibling
GENERAL PREVENTION
- Prevention of premature birth with education and regular prenatal care
- Antenatal corticosteroids
- Manage any medical issues appropriately.
- Healthy behaviors including diet and exercise
- Avoid exposure to tobacco smoke, alcohol, and illegal drugs.
DIAGNOSIS
HISTORY
Preterm neonates with worsening respiratory distress beginning shortly after birth and progressing over first few hours of life.
PHYSICAL EXAM
- Tachypnea
- Grunting
- Nasal flaring
- Subcostal and intercostal retractions
- Decreased breath sounds
- Cyanosis
DIFFERENTIAL DIAGNOSIS
- Early-onset group B streptococcal pneumonia and/or sepsis
- Transient tachypnea of newborn
- Meconium aspiration pneumonia
DIAGNOSTIC TESTS & INTERPRETATION
- CBC and blood culture to rule out sepsis and pneumonia
- Electrolytes: Monitor for hypoglycemia and hypocalcemia.
- Arterial blood gases (ABGs)
- Hypoxemia (which responds to supplemental oxygen)
- Features of respiratory and metabolic acidosis
- Chest x-ray (CXR):
- Diffuse reticulogranular pattern (ground-glass appearance)
- Air bronchograms
- Low lung volumes
Diagnostic Procedures/Other
Echocardiogram: Consider if murmur is present to evaluate for patent ductus arteriosus (PDA) and contribution to lung disease due to L ’ R shunting.
Test Interpretation
- Macroscopically: uniformly ruddy, airless appearance of lungs
- Microscopically: diffuse atelectasis and hyaline membranes (eosinophilic and fibrinous membrane lining air spaces)
TREATMENT
- Along with antenatal steroids, surfactants improve survival for preterm infants.
- Surfactants are now recommended routinely as early in the course of RDS as possible.
GENERAL MEASURES
- Warm, humidified, oxygen-enriched gases if the neonate is ventilating effectively
- Continuous positive airway pressure (CPAP) if infant is active and breathing spontaneously (3)[A]
- Positive-pressure ventilation per ETT via conventional mechanical ventilator (CMV) or high-frequency oscillation ventilator (HFOV) if respiratory failure occurs (i.e., respiratory acidosis, apnea, or hypoxia despite nasal CPAP) (3)[A]
- Transcutaneous monitors to measure CO2 tension as necessary
- Pulse oximetry
- Umbilical artery catheter placement for continuous BP monitoring and sampling ABGs
MEDICATION
- Pulmonary surfactant (3)[A]
- Side effects: Bradycardia, hypotension, airway obstruction/endotracheal tube blockage with administration; rapid changes in tidal volume due to increased compliance can cause a pneumothorax and small risk of pulmonary hemorrhage.
- Precautions: Transient adverse effects seen with the administration of surfactant may require stopping administration and alleviating situation; may proceed with dosing when stable
- Contraindications: presence of congenital anomalies incompatible with life beyond neonatal period; infant with laboratory evidence of lung maturity
- Perform frequent clinical and laboratory checks so that oxygen and ventilatory support can be modified to respond to respiratory changes (3)[A].
ISSUES FOR REFERRAL
Comorbid conditions associated with prematurity may require consultation during the course of the infant 's NICU admission, including PDA (cardiology consult), necrotizing enterocolitis (NEC) (gastroenterology), retinopathy of prematurity (ROP) (ophthalmology), etc.
ADDITIONAL THERAPIES
Treat associated problems of prematurity.
INPATIENT CONSIDERATIONS
Admission Criteria/Initial Stabilization
All neonates with respiratory distress require evaluation, monitoring, and treatment in a NICU; treatment may be required in the delivery room.
IV Fluids
- To maintain blood pressure and perfusion, when necessary
- To provide optimal fluid balance, provide nutritional support
Nursing
- Supportive care
- Thermoneutral environment
- Respiratory monitoring
- Establish relationship with family to provide education and emotional support.
Discharge Criteria
- Should have stable vital signs and pulse oximetry before discharge
- Medical home and support services should be in place.
ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
Following discharge, infants should be followed closely by their physicians to monitor growth and respiratory symptomatology.
DIET
As clinically indicated
PATIENT EDUCATION
- Educate parents regarding the risks in subsequent pregnancies.
- Advise parents regarding potential issues with chronic lung disease.
- For patient education materials favorably reviewed on this topic, go to Boston Children 's Hospital Web site (http://www.childrenshospital.org) and search for respiratory distress syndrome in the "My Child Has " window.
PROGNOSIS
Prognosis and outcome are highly dependent on gestational age and birth weight. Almost half of the infants in Jarjour study who were born at or <25 weeks ' gestation had significant neurodevelopmental disabilities on short- and long-term follow-up.
COMPLICATIONS
- Complications specific to NRDS
- Pneumothorax
- Chronic lung disease, bronchopulmonary dysplasia (BPD)
- Pulmonary interstitial edema (PIE)
- Additional complications may occur related to therapeutic interventions and comorbid conditions.
REFERENCES
11 Kochanek KD, Murphy SL, Xu J, et al. Mortality in the United States, 2013. National Center for Health Statistics Data Brief No. 178. http://www.cdc.gov/nchs/data/databriefs/db178.pdf. Accessed 2015.22 Ancel PY, Goffinet F. Survival and morbidity of preterm children born at 22 through 34 weeks ' gestation in France in 2011: results of the EPIPAGE-2 cohort study. JAMA Pediatr. 2015;169(3):230 " 238.33 Sweet DG, Carnielli V, Greisen G, et al. European consensus guidelines on the management of neonatal respiratory distress syndrome in preterm infants " 2013 update. Neonatology. 2013;103(4):353 " 368.
ADDITIONAL READING
- Finer NN, Carlo WA, Walsh MC, et al. Early CPAP versus surfactant in extremely preterm infants. N Engl J Med. 2010;362(21):1970 " 1979.
- Hamrick SE, Hansmann G. Patent ductus arteriosus of the preterm infant. Pediatrics. 2010;125(5):1020 " 1030.
- Jarjour IT. Neurodevelopmental outcome after extreme prematurity: a review of the literature. Pediatr Neurol. 2015;52(2):143 " 152.
- Stoll BJ, Hansen NI, Bell EF, et al. Trends in care practices, morbidity, and mortality of extremely preterm neonates, 1993 " 2012. JAMA. 2015;314(10):1039 " 1051.
CODES
ICD10
- P22.0 Respiratory distress syndrome of newborn
- P22.0 Respiratory distress syndrome of newborn
ICD9
769 Respiratory distress syndrome in newborn
SNOMED
46775006 Respiratory distress syndrome in the newborn (disorder)
CLINICAL PEARLS
- Surfactants are used routinely as early in the course of RDS as possible.
- If an infant has a murmur, consider an echocardiogram to rule out PDA and shunting.
- Prognosis and outcome are highly dependent on gestational age and birth weight.