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Published on: November 20, 2015
Respiratory morbidity in late preterm infants
Cláudia Correia1, Gustavo Rocha2, Filipa Flor-de-Lima3,2
1Faculty of Medicine of Porto University, Alameda Professor Hernâni Monteiro, Porto, Portugal - mimed10081@med.up.pt.
Insights
Late preterm infants face significant respiratory risks like respiratory distress syndrome (RDS) and transient tachypnea of the newborn (TTN). Cesarean delivery and lower gestational age are key risk factors for these adverse respiratory outcomes.
Area of Science:
- Neonatal Medicine
- Pediatric Pulmonology
- Obstetrics
Background:
- Late preterm delivery (34-36 weeks) accounts for 74% of preterm births.
- These infants exhibit increased respiratory pathology, including respiratory distress syndrome (RDS) and transient tachypnea of the newborn (TTN), compared to term infants.
- Ventilator support is also more common in late preterm infants.
Purpose of the Study:
- To evaluate respiratory morbidity and mortality in late preterm infants.
- To identify risk factors associated with RDS and TTN in this population.
Main Methods:
- Retrospective study of 498 newborns born between 34+0 and 36+6 weeks gestational age.
- Exclusion criteria included major malformations, chromosomopathies, hydrops fetalis, and congenital TORCH infections.
- Data analysis focused on respiratory outcomes and associated maternal and neonatal factors.
Main Results:
- 44 infants (8.83%) experienced RDS or TTN.
- Respiratory morbidity linked to lower gestational age, male gender, cesarean section, peripartum antibiotics, maternal overweight, and nulliparity.
- Newborns with RDS required more resuscitation, intubation, oxygen, ventilation, parenteral nutrition, and had longer NICU stays than those with TTN.
- Cesarean section and resuscitation with endotracheal tube were independent risk factors for respiratory morbidity.
Conclusions:
- Late preterm infants, especially those born after 35 weeks without antenatal corticosteroids, remain at high risk for adverse respiratory outcomes.
- Cesarean section is an independent risk factor for respiratory morbidity, necessitating efforts to reduce its rate.
- Evidence supports extending management guidelines into the late preterm period.
Background:
Late preterm delivery (74% of all preterm births) increases the incidence of respiratory pathology, namely respiratory distress syndrome (RDS), transient tachypnea of the newborn (TTN) and the need of ventilator support when compared to term delivery. The aim is to evaluate the respiratory morbimortality in late preterm infants and the risk factors associated with RDS and TTN.
Methods:
Descriptive retrospective study of all newborns of 34+0 to 36+6 weeks of gestational age, born at our center between September 1, 2012 and August 31, 2015. Those with major malformations, chromosomopathies, hydrops fetalis and congenital TORCH infection were excluded.
Results:
A total of 498 newborns were studied, 44 (8.83%) of them with either RDS or TTN. Respiratory morbidity was significantly associated with lower gestational age, male gender, caesarean section, exposure to peripartum antibiotics, overweighed and nulliparous mothers. RDS newborns had a significantly higher need for resuscitation, endotracheal intubation, oxygen therapy, early invasive ventilation, parenteral nutrition and a longer NICU stay when compared to newborns with TTN. 55% of the patients with RDS had 35+0 to 36+6 weeks of gestational age, moderate or severe RDS and required mechanical ventilation; six needed surfactant. Caesarean section and resuscitation with ETT were independent risk factors for respiratory morbidity.
Conclusions:
Late preterm remain at risk for adverse respiratory outcomes, particularly newborns delivered after 35 weeks, whose mothers are not given ACS and still have considerable morbidity. Growing evidence supports the possibility of extending the management window further into the LPT period. Caesarean section was an independent risk factor for respiratory morbidity and efforts should be undertaken to reduce the procedure rate.
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