Related Experiment Videos
Timing of antenatal corticosteroids and neonatal pulmonary mechanics
C McEvoy1, S Bowling, K Williamson
1Department of Pediatrics and Obstetrics, Sacred Heart Hospital, University of Florida, Pensacola, Florida, USA.
Insights
Multiple courses of antenatal corticosteroids improved infant respiratory compliance and lung function. This suggests repeated surfactant production induction is possible, even with prior corticosteroid exposure.
Area of Science:
- Neonatal Medicine
- Pulmonology
- Pharmacology
Background:
- Antenatal corticosteroids are used to mature fetal lungs.
- The effects of multiple courses on infant lung mechanics are not fully understood.
Purpose of the Study:
- To compare lung mechanics in infants exposed to multiple antenatal corticosteroid courses with controls.
- To assess the impact of timing and dosage of antenatal corticosteroids on infant respiratory outcomes.
Main Methods:
- A matched cohort study comparing 18 infants receiving multiple corticosteroid courses (within 7 days of delivery) to 18 receiving one course (>7 days prior) and 18 untreated infants.
- Measurement of respiratory compliance and functional residual capacity within 36 hours of birth.
- Statistical analysis using analysis of variance (ANOVA).
Main Results:
- Infants receiving multiple antenatal corticosteroid courses showed significantly higher respiratory compliance compared to both remote and untreated groups (P <.02).
- Functional residual capacity was higher in the multiple-course group than the untreated group (P <.05) and similar to the remote group.
Conclusions:
- Multiple antenatal corticosteroid courses, when delivered within 7 days of dosing, enhance infant respiratory compliance.
- The findings suggest that the surfactant production pathway can be repeatedly stimulated by corticosteroids.
- Increased functional residual capacity in infants treated remotely may indicate lung maturation independent of surfactant induction.
Objective:
We sought to compare lung mechanics in infants treated with multiple courses of antenatal corticosteroids with those in matched control infants delivered >7 days from dosing and those of matched untreated infants.
Study Design:
Eighteen infants who received multiple courses of corticosteroids and were delivered within 7 days of dosing were matched with 18 infants who received 1 course of corticosteroids >7 days before delivery (remote) and 18 untreated infants. Respiratory compliance and functional residual capacity were measured within 36 hours. Differences were compared by analysis of variance.
Results:
Infant demographics were similar. Respiratory compliance was higher in the multiple-course group than in the remote or untreated group (P <.02). Functional residual capacity was higher in the multiple-course group than in the untreated group (P <.05) but similar to that found in the remote group.
Conclusion:
Babies delivered after multiple courses of corticosteroids and within 7 days of dosing demonstrated improved respiratory compliance compared with untreated and remotely treated infants. This suggests that the enzyme system responsible for surfactant production can be repetitively induced despite prior treatment with corticosteroids. The increased functional residual capacity in remotely treated infants may reflect a maturation of lung architecture independent of surfactant production.